aan de rijks-universiteit te utrecht
op gezag van den rector magnificus
jhr. dr. b. c. de savornin lohman
hoogleeraar in de faculteit der rechtsge-
leerdheid volgens besluit van den senaat
der universiteit tegen de bedenkingen van
de faculteit der veeartsenijkunde te
verdedigen op donderdag 4 juni 1931 des
namiddags te 4 uur door

liy V. .7. .T. FOFKIE, M.R.C.V.S., Sul)-])iiector of Yeterinary
Services, Oiiderstepotn-t.

Ix the liteiatiire available, no reference to a complete and systematic
stu(ly of the liaeniatolof^y of sheep infec.\'ted with wiveworni
(Ilacmonvlnis coiitortns) has been foiiiul. Tliat anaemia develops as a
result of the action of the f-astro-intestinal worms, is well known;
and. under field coudifions, jiale mucous jneinbranes and the most
extreme degrees of badly staining and watery blood, are features
which are conunonly associated with the effects of internal parasites.
How the anaemia is hrouglit about, and what part individual species
of parasites ])lay in its i)r()(lucti()n, are points that have iiot been
jjroperly elucidated.

The main object of this study is the pathogenesis of the anaemia.
In sncli an investigation it is necessary to pi\'odnce in woiiu-free sheep,
under ])roi)erly controlled experimental conditions, a ])rogressiYe and
])referably fatal anaemia, i)y tlHj administration of ]mre faeces
cultures of the i)arasites. The .subject matter of this work can con-
veniently be stib-divided into:

AVeekly observations on the blood were recorded, before infection
and throuadiout the experiment, until the animal died as a result of
tlie parasitic infestation. In order that reliable conclusions can be
drawn as to the eÖects produced in animals by particular parasites, it
is necessarv (1) that the animal host at the time of the commencement
of the experiment be free from infestation, and (2) at the time of the
completion of the experiment no other parasites than the one under
investigation be recovered at post-mortem examination. Th.ese are
the ideal conditions that must he aimed at, but it must be confessed
that only rarely are they completely attained in practice, notwith-
standing that the most elaborate precautions are strictly maintained.

Yeglia (1928) describes in detail the method employed by him
for rearing and maiutaiuing worm-free lanilis at this Institute. He
removes the lambs from their mothers soon after birth, hand-rearing
them in specially constructed cages with raised floors. In this way it
is possible to control more or less successfully the worm infection of
particular animals, but it was impossible to prevent tliis entirely,
although such infestation Avith parasites other than those with which
the experimental animals were infected was jnesent only to a small
and negligible extent.

Sixteen lambs reared in this way by Veglia were used in the first
series of these experiments. Later oil, when no moie such lamhs were
available, young slieep. entirely fiee from worm iiife.station, were
bought from certain farms in the Karroo. The c(miplete absence of
worm infestation was determined by making post-mortem examina-
tions of some animals that were born and reared under the same
conditions as others used for these exiierimeiits and was confirmed
before these animals were actuallv drafted into an experiment by
careful faeces cultures. This work was courteously directed by my
colleagues. l)rs. Veglia and Abiniiig.

Lambs or young sheep were .selected for these experiments because
of the generally acce])ted view tliat ycning animals are more suscep-
til)le than are oldei\' animals to the effects of i)arasites. Hadwen
(192.\')), referring chiefly to Ascariasis in horses, maintains that tliis
is due to an immunity or tolerance acciuired or (levelo])e(l hy older
animals as a result of infection with jjaiasites. Young animals, not
having had an oi)])oitunitv to develoj) tliis power of tolerance, suffer
.severely when they I)ecome infected. \'IMiis immunity and tolerance is
due to aiiti-suhstances and eosinophiles, both of which function in
neutralizing the cast-ofV nroducts of the worms. He believes tliat the
eosinophiles secrete in addition to these agents wliich neutralize effete
porducts of worms, a .substance which i)aralyses oi\' kills tlie worms
them.selves. lie states that the i)ercentage of eosinophiles in the
circulation may be low, or even altogether absent iii severe cases of
])arasitism. There is an ai)parent leucojienia as far as the eosiiiopiiiles
are concerned, but this is due to their withdrawal from the circula-
tion and their coiiceiitration aiound the jjarasites in the tissues.
Similarly, an eosinophilià may mean that the ])arasites have been
overcome. In .such cases the exce.ss of eosono])hiles has again returned
to the circulation (from which they gradually disajijiear).

The use of young lambs foi- these experiments has the additional
advantage that they are less likely to be seriously infested with any
parasite other than the one under investigation.

It is naturally e.ssential that pure cultures of the parasites should
be iised for infecting experimental animals. One may have the good
fortune to obtain a pure culture from a sheep that happens to harbour
the pure infestation of the parasite that it is intended to u.se. In
cases of mixed iiil\'e.station, undesirable para.sites can he destroyed by
specific drugs, which must iu)t be parasiticidal for the parasites which
are to be cutivated or a pure culture can he obtained by keeping a
sample of mixed faeces culture until the unwanted larvae have died
out. ^Mihinig (1930) shows that eggs of Triclwstronriyhts spp. con-
taining coiui)lete embryos are more resistant to desiccation than such
eggs of Hdcinoiiclnis confortiis, ()exop}i(it(jostomum columhiamim and
Stront/i/Ioidcs luipiUnxus. In the same paper this author discusses a
successful method of producing a pure infestation of Oesopluigostoines
in slieei) by administering the adult nodular worms in .saline per
rectum.

A further method consists in infecting worm-free sheep witii
adult males and feuuiles of the parasite. In some cases eggs are
])asse(l in the faeces in due course, and in this way a pure culture
can be obt.iiiied with wiiich further clean aiiinials can he infected,
and rich cultures fi-oni these (;an he used for gross infection of exjjeii-
nieiital animals.

Keceiitly Stoll (li)2{)) (lescril)e(l an ideal inethod for the natural
infection of animals on the pasture. Natuial infection of the pasture
is introcbu-ed by uu\'ans of lambs which have been given larvae deve-
loped li\'oni egg\'s obt liiu\'d from a single female wiiewonii. If it is
])()ssible to i)revent gro.ss iiife.station of the pasture by otiu\'r i)arasites.
one should with this method he able to study the haeuiatology of
haenioiu\'hosis under natural conditions. This is very desirable, as
noiu\' of the animals artiticially infected with wireworm and k«\'|)t
uudei- controlled experimental conditions in tiie stalile develo])e(l any
(»edematous swellings, e.g. quot; bottle jaw,quot; which are characteristic
clinical feattires of vei\'uiinosis.

Tiie experimental aninuils were infected ])y injecting a saline
susi)ensioii of larvae, obtained from faeces cultures, into the mouth
by uu»ans of a hyixxh-ruiic syringe without the needle.

Pure faeces cultures of the parasites liaviug been obtained on tiie
one hand and clean animals to infect on the othei\'. it was thought that
no gi-eat ditiiculty would be experienced in producing tyi)ical cases
for haeniatological study. Accordingly a fairly audiitious i)r()!gt;:raunue
was drawn u]) for the comjiarative study of the lilood of a number of
animals infected at the sauugt; time with ])ure cultures of jjaiasiles
commonly encountered in the gastro-intestinal tract of sheep under
natural conditions in South Africa. These are (1) /Idruinnrlnts roii-
tnrtii.i, (2) Ovsopluit/fisioiniiiii coluinhlaiiinn, (gt;]) Various s])pcies «if
TrirliDstroiif/i/lus, M) Siiniif/i/Joi\'dcs piiju\'llosus.

When mixed cultures of these jiarasites were used, no difHculty
wad oxixMienced in artificially jiroducing a fatal panvenninosis, but

the production of a progressive disease m sheep by infecting these
with pure cultures of these parasites was found to be altogether a
different matter. This was especially the case when the sheep were
stabled and properly fed on a well balanced ration. There are quite
a number ot factors which may, to a greater or lesser degree, be
responsible for this, viz. : —

(1)nbsp;Under field conditions the worm infestation is usually a
mixed one, and it seems that the animal is less able to
withstand the onslaught of an attack at several different
portions of the gastro-intestinal tract ;

(2)nbsp;Where the grazing is poor, particularly in quality, the
parasites thrive exceedingly at the expense of the host ;

dent ill those areas where no jackal-proof fencing has
been carried out, for it becomes necessary, in order to
protect the sheep against the ravages of this vermin, to
drive them to the shelter of kraals every night. ihis
increases the amount of daily exercise of these animals,
with the result that the resistance to the parasites is
decreased, enabling them to bring about deleterious effects
more rapidly, especially in tliose sheej) in which the
anaemia is already present ;

(4)nbsp;The method of infection is probablv also of importance.
Yeglia (li)18) believes that the larvae, in the case ot
natural infection in haemonchosis, pass into the rumen ot
sheep with the solid food, whereas when 10 c.c. ot saline
suspension of larvae are injected into the mouth, the larvae
may pass straight into the abomasum with this Ikjuk! and
arequot; in the.se circumstances liable to pass into the lute.stine
without having had time to undergo those changes which
enable them to remain in the abomasum.

It was only after many disai)pointments and with a great deal of
difficulty that%i sufficient numlier of typical, fatal cases of pure
haemonchosis were artificially produced for haematologicai study.
The work on the haematology and pathology of ( le.sopiiag^ostoimasis
and Trichostrongylosis, will be discussed in later papers. In connec-
tion with Strongyloides papillosus, no haematolognnl observations
will be recorded (numerous observations were actually made) as in
not a single instance was a progressive disease pniduced, in s]ute of
the fact that many of the animals infected passed faeces from which
strong colonies were obtained by faeces cultures.

Throughout these experiments, all the animals, including the
controls, were kept under identical conditions of hcmsing, feeding and
watering. Xo special attem])t was made to draw the blood at definite
intervals before or after watering. It ^vas thought that the most
uniform results wtmld be obtained if the amount of water that the
animals consumed was allowed to be regulated by the natural deve-
lopment of thirst. Tn order to achieve this, a identiful supjdy of
water was made always available. On this account it is believed
that no undue concentrtfion of the blood could have occurred at any
time as a re.sult of diminished ingestion of water.

The technique developed by Xeser (1923) aud exhaustively dis-
cussed by him in his work on quot; The Blood of Equiiies,quot; is with few
modifications applicable to haenuitological work in sheep. The
methods of examination employed are exactly those advocated by
Xeser, except where such modifications were foiuul to be necessary,
and details of the latter only will be discussed. For the other details
Xeser\'s work should be consulted.

It is obvious that a direct examination of the Avhole blood Avould
lt;gt;ive the most accurate absolute results concerninf;\' tlie niorphololt;gt;\'y
aud other attributes of both the erythrocytes and the leucocytes, but
where a systenmtic examination of the blood of a number of sheep had
to be completed in one day. it was clearly iiiipos.sible to nmke deter-
inination.s on the whole blood.

Kossdale (1923) compares the haematocrit results obtained wlien
worlduf^f with whole blood and citrated blood. Solid crystals were
used, as well as definite jjioportions of citrate .solutiou.s, .for which a
correction was made afterwards. In a luiniber of cases inve.stifgt;\'ated,
lie found the greatest deviation from the mean volume index to be 4
])er cent, in the ca.se of wliole blood, 11 per cent, in the ca.se of citrate
crystals, and 14 i)er cent, where citrate solution was employed. He
concludes that the addition to the blood of citrate or oxalate alVects
the haematocrit readinj^s by reducin»;\' the i)ercentafgt;e volume of led
cells, unless that ])articular proportion of citrate to i)loo(l be chance(l
upon which happens to be isotonic with tlie particuhu- blood under
iiivestij^ation. Hossdale j^ives a c()nii)rehensive review of anti-
coafjfulants u.seil by various workeis, and lie (juotes in each case tlie
haematocrit values obtained by these authors when centrifuf^inj;\' at
certain definite speeds sanii)les of blood of which the red counts, and
ill some cases aveiajiv measurements of the red cells had been
determined.

\'i\'he anticoafiulaiit selected was the one used by X^eser for hor.se
1 looil. This consisted of a per cent, citrate solution used in the
l)i()portion of .1 c.«\'. citrate to 1 c.c, of blood. AVith this method
(|uite uniform relative residts were oi)tained. Brym-honenko and
Steppiihn (li)27) claim that Hayer 20\'), when injected intravenously,
will prevent coaji-ulation of the blood for some hours. This would l)e
ail ideal niethocl for haeniat()lofgt;ical work, ])rovide(l the dru«;\' has no
s|)ecific etVect on any of the elements of the blood. The chiei\' advan-
tages of this method of collectinlt;r the blood would be: (1) If coajfula-
tion is prevented for some hours, there is ami)le time for a C()n)])lete
systematic study of several sami)les. (2) Xo measured amount of blood
need be drawn. Errors in haenrntolof^-ical studies are j\'reipieiitly due
to the iiuu\'curate measuring- of the blood when it is beinp: withdrawn
from the vein. (3) Xo changes in isotouicity caii jiossibly occur, .so
that values (le])endeiit on the size of the red cells will be more reliable.
Hirudin as an anticoajiulant was not available.

When an anticoafjulant is used, the iiossibility of error is less
the larffer the amount of blood that is drawn. Where, however.

anaemia is studied, particularly in a small animal like the sheep it
is advisable that only small amounts of blood be collected, so that
the factor of bleeding cannot be blamed for the production oi the
anaemia; consequently small bottles with narrow necks, measuring
approximately 6 c.c. were ntilized for collecting the blood.

The examination of the blood included the study of (1) a study
of the erythrocytes—(fl) the red counts, (b) the red precipitate or the
percentage volume of the red cells, (c) the percentage of haemoglobin,
(d) the size of the red cells, (e) the viscosity. (2) The leucocytes—
(a) the total white counts, and (h) the differential counts.

This was obtained bv centrifuging the citrated blood in an electric
centrifuge running at lquot;,500 revolutions per minute for (gt;0
The centrifuge tubes were calibrated as advocated by .\\eser
In the horse this author obtained constant centrifuge readings in
10 mintes, irre.spective of whether the centrifuge was running at
medium or high speed. At a low speed (250 revolutions per quot;incite)
the same reading was obtained in 15 minutes. gt;eser concluded tliat
within certain limits of speed the volume of the red corpuscles in
e(|uine blood is in no way influenced by the speed.

The blood of the sheep as compared with that of the horse, takes
a much longer time to precipitate completely, as will he .seen from tiie

A young healthv Merino sheep, No. 24197, was bled daily from the
jugular vein, 20()-.\'5()() c.c. of blood being removed at a time, until a
severe degree of anaemia was produced. Before Ideediiig, this animal
had a red count of 15 million per c.mm. of blood, a percentag^\' vo nine
of 35, and 102 per cent, of Iiaemoglobin. As a result of the bleeding,
the red cell counts, the percentage of haemoglobin and the red
precipitate rapidly decreased. When the sheep had developed what
could be regarded as a mild degree of anaemia, with a red count ot
4.9 millions per c.mm., a haemoglobin of 45 per cent, and a red
precipitate of 15, the precipitate during centrifugalization was read
every 10 minutes and the blood from another but normal sheei), No.
24188, was treated in the same way, at the same time, and in the
«ame centrifuge running at 1,500 revolutions jier minute. The results
obtained were : —

Iwo days later, wlieu a more severe degree of anaemia had
developed, witli a red count of 2.7 million per c.mm., thep reciT)itate
was again read at intervals of 10 minutes, together with that of the
same normal sheep. The results obtained were •_

iMom the above it can be concluded that in normal sheep constant
red cell percentage volume readings are obtained in G0-7() minutes
when citrated blood is precipitated in an electric centritWe runnin\'o-
at 1,500 revolutions per minute. In the case of anaemic blood con-
stant readings are obtained very much earlier. In very severe de-n-eeti
of anaemia, constant readings are obtained in 2()-;5() niinutes time^-uid
in less severe degrees of anaemia in 40-50 minutes. In this woric
therefore, the precipitate was read as a routine procedure after (K)
minutes with the centrifuge running at 1,500 revolutions per minute.

This was determined calorimetrically in a Duboscj calorimeter -i
Newcomer disc being u.sed as the standard. The a])plicati()n of this
disc to haemoglobi II determiiiatloiis was discussed by Newcomei- in
1!)1!). Daylight illumination was used as it was found difficult to
match the colours with the artificial light available. (Iccasionally
when ob.servations were made on chmdy days, it was found difllcult
to obtain consistent readings. Thiougliout quot;this work an ay(gt;rage of
10 calometric readings was taken, tyi)ical e-xamjiles of which are:_

S.2, 8..\'{, 8.2, 8.2, 8.2, 8.2, 8.2, 8.4—giving an average reading of
8.2. AVhen this is read again.st the chart sujjplied by tiio
manufacturers, the value of !)2 per cent, haemoglobin is obtained.

Sheep Xo. 14li)7—showing anaemia—dilution 1 in 200 IT (i
17.7, 17.7, 17.8, 18.0, 17.lt;). 18.0, 17.(i, 17.(i. 17.!) giving an avera\'oe
of 17.8, which is eiiuivalent to 42 igt;er cent, of haemoglolmi, \'quot;quot;

The Newcomer disc was standardized against Van Slyke\'s
gasometric method, and the chart supjilied by the manufacturers of
the disc in the quot;Williamson standard was converted into the llaldane
standard. Newcomer (l!)2.\'l) de.scribed quot; a new optical instrument for
the determination of haemoglobin.quot; This should be a very coii-
venieiit ai)paratus, as one is al)le to read off directly on the instrument
the percentage of haemoglobin.

The diluting fbiid is N/10 hydrochloric alt;-id wiiicii converts the-
blood into acid haematin. The chart sui)plied with the di.sc is only

prepared for reading dilutions of 1 in 200 and 1 m 500
the dilution of 1 in 200 was employed.

•wiM solution It was found convenient io fill tl»o ttasu T() ^unni
in 0() -e iie \'\' )() (• mark and then to run in the citrate, blood as

added to tlie 200 cc. mark. Flasks with long necks having the
200 cc. mark on the neck, are the most convenient. The 1 cc. pipettes
used were either standard or previously- checked against a standard
pipette.

The size of the red cells was determined by direct microscopic
measurement witli an quot; Okular Schraubenniikrometer,quot; haviuquot;- a G
compensating ocular. When this apparatus is used with a 2\'\'nim
apochromatic lens, tlie figures obtained must be multiplied by .14 in
order to convert them into values of microns. It is realized that the
true average size of red cells in .stained smears will not be obtained
by measuring even 400 or more red cells in numerous fields, and as
this is most exacting work, requiring a great deal of tinie, only
relatively few cells (-ould be measured, mainly with the object of
obtaining corroboiative evidence as to whether any increase at all in
the size of the cells had occurred, as was suggested by changes in the
colour index and in the Aolume index. Pyper (l!)2y) describes a
diffraction method whereby the true average size of the red cells in
suitably i)repared un.stained smears can be simply and quickly deter-
mined .spectro.scopically. If a snfiicient number of smaller anil laroer
cells are present in such smears, they will also produce measurable
spectra, conse(iuently this author can by this method calculate\'the
diameters of tlie smallest, the average,\'and the largest cells. The
method was unfortunately not available for a])plication in this study.

Hess\' viscosimetei- was used. Schiidde and Naegeli (1!)21) give
a detailed de.scription of this apparatus. Unless tlie deterniinatTon.s
are made with dexterity, the values obtained can be very unreliable.
In the tables submitted, the temperatures at which deteiniinatioris
were made are stated, but no corrections for these were made. It
noteworthy that in some cases in which thei-e was ob.served an
apparent agglutination of red cells in the counting chamber, the
viscosity was abnormally high for the j)articular blood, if it is con-
sidered that more or less normal values were obtained for the red
counts, haemoglobin and i)ercentage volume of red cells.

The total while cell counts were made by the usual methods and
the differential counts were made according to Neser\\s (1!)2.\'{) modifica-
tion of Fhrlich\'s method.

As already stated it was at first intended to make a comparative
haeniatological study of sheep with pure infestations of Hacmonchus
contortus, various specias of Trirhosiroiuji/his, (h\'sophoijosiomvm
coluiiihi/nnnn- and Stroiit/i/loidc.i //(ipillosirs.

Seventy shee|) were used in the.se exjieriments. Thirty-eight
were infected with //(icinonrhus roiitoriits, eleven with \'fnrhnsiron-
!/t/hi.s, .seven with Ocxophdfjostoinutn columhidintm, three with

Sheen infected with a pure or practically pure culture of
can be conveniently ^^^^^^^^
Xcts observed as : (A) those sheep in which a progressae and iata
£ e wÏÏ produced^ and (B) those in -Inch an anae^
from which the animals soon recovered -quot;^thout nedicimU ^
other treatment-these can be desig;iuited as l•eco^el^ cases and
in whicli no effects were observed. (C) Controls.

The outstanding feature of these lt;..ses is a
This is conveniently illustrated in the acconipanj ng ahies ami
graphs, where the changes i^n the red cells are reco de n^
are concerned (1) the number of red cells, (2 the^pe ^
haemoglobin, (3) the percentage volume of led (ells (pie. ipitate;,

twenty-three either resisted -testation^ ^^^ ^ ^ . s^jwls
of infection. On the nine cases innbsp;h \'\'nbsp;, -ii i,. „resented

rate of approximately 1,000 larvae per day until .)2,0( 0 j^V^\'
been given. Infection was, therefore, completed towards 1 (,.(,.2..

Haematol Of}!/ of Sheep No. 1(1027.
During the first fourteen (14) days after infection tbere is an
increase in^he nundgt;er of red cells with a

creased activity. After that there is a progressive lt;hH-rease in 1
he number of red « ells, (2) the percentage «.f haenu.globin, an. (3)
tl e percentage volume of red .-ells, except for a slight increase which

Method of treatment: Infeetion ronunenred 27.4.27, ijirinij 1,()()() hrrae of Haenionchus
coiitoitus per daij until 52,000 larvae had been administered.

occui^ (himio. the peno.l from the 19th until the 25th of May. From
li quot;If oV\'quot;\'\' June the decrease of 3 million red cells pL\'c.nnu.
iL ZT\' /nbsp;laeuioglobin, and of 11 per cent, iu

clinical evidence of icterus or haenioglobiuuria was present The
annual was destroyed on the 5th of .July, on which day the red
count was l.(, million per c.cm, of hlood/the haeiuoglobiiJ 1U.5 per
cent, and the precipitate a])proximately 5 i)er cent.

nhJl\'\'?\'^ the course of the disease the only clinical syinptonis
obseiyed were (1) pale mucous membraues. paiticularlv the con-
junctivat, the buccal and the anae (just before death the pallor was
of an extreme .legTee) (2) accelerated respirations, and (-3 frequent
pulse, with pounding heart action, e.specially i„\'th« L.ter
ihe accelerated respirations and fre.iuent heart action were DaitFcu-
larly noticeable on exertu)n. There was no clinical evidence of
icterus or oedema.

Chanjjrs in the l{clt;1 Celh.—\\n referring to Table Xo. 1 it will
P foquot;nbsp;gt;uoipliquot;logical changes occurre.l in the red cells until

]0.(..2( ()n that day punctate basophilia was for the first time
observed. During the further course of the disease, and as the
anaemia became progressively worse, the morphological clian-es be
came more pronounced. On ;K).(i.27 and 5.7.27, when the anaemia
was ()1 an extreme degree, there was well marked anisocytosis and
there were jmikilocytosis, polychromasia, punctate bason],iHa nnd
Jolly bodies in (pute a number of red cells, but in this particul-ir
case no normoblasts were identified.

C/ioiiijes III Size of ilic Hal r\'f\'//.v.—As already stated Pyiier\'s
(l!)2f)) ai)j)aratus for determining .|uicllt;ly and siin])ly the avora-ro
size of the red cells in snu\'ars was not available. To measure s-Ty
400 cells with a micrometer leiiuires a great deal of time and eveii
if this is done the true average size of the red cells in smears will
not be obtaiiu\'d with any degree of accuracy. It is, however.\' imix)!--
tant for (he interjiretation of changes in colour and volume indict
to know if changes in size have occurred. In this particular sheen
measurements were made, of a small number of cells from smears made
0) liefore infection, (2) when a marked decrease in the oxygen Carry-
ing cai)a(;ity of the blood was taking place, and (;{) towards the eiid
()f the disease. In all three cases 15 cells were measured in several
fields. The results are: —

The relationshi]) of the haemoglobin content to the number of
red cells, i.e., the colour index, the relationship of the haemoglobin
lt;0 the precipitate, i.e. the volume colour index, and the relationshii)
of the ])recipitate to the number of red cells, i.e. the volume index
will be fully discussed elsewhere in this jniper. This being the case\'
it will only be necessary to indicate briefly and without going info
any details the more imj)ortant change.s that have occurred.

The Colour Index.—There is a tendency towards a decrease oi
tliis index, probably due to a relative decrease in tlie haemoglobin
content of the cells and to an increase in the size of the cells.

The Volume Colour Index.—There is at first a tendency towards-
an increase of this index (up to 1Ü.G.2T) probably dne to a decrease
in the size of the red cells. Towards the end of the disease the index
is definitely decreased. This would indicate a relative deficiency in
haemoglobin and an increase in the size of the red cells.

Volume Index.—There is at first a tendency towards a decrease
of this index, indicating a decrease in the size of the red cells, biit
towards the end of the disease the volume index increases. ihis
confirms the conchrsion previously arrived at, that ^
the size of the red cells had occAirred. As previously stated, too teAx
cells were measured in order that reliable conclusions .as to the true
average size of the red cells could be drawn; quot;evertheless, the
measiuements made suggest that the cellsnbsp;\'\'

instance, are on the whole smaller than the cells on 21 .4.2lt;. 11 eie
is no doubt at all that on .\'50.0.27 the cells were dehnitely larger than
before infection and during the earlier stages of the disease.

The cells .stained less intensely in the later .stages of the disea.se
and many had a vacuolated appearance. Although un.stained central
areas are sometimes encountered in cells of apparently nonnal sheep,
these staining reactions would tend to confirm the con.-lusion that a
relative deficiency of liaemoglobin was pre.sent.

Changes in. the Leueocj,tes.-^o .dianges which can be regarded
as pathogonomic. for haemonchosis were observed Soon after the led
cells begin to decrease in number a decrease in the to al ;\\uuiber of
leucocytes also occurs, but during the later sages of the « «ease t e
total num}gt;er of leu.:ocytes again increases If the
be referred to, it will be observed tl.at tins increase af ect. n i 1
the neutrophiles. The neiKrophile counts are at then- b.west uhen
the first evidence of nunphological changes in the red ,.ells is noticed,
I.ater on, when the.se morphological changes in the red cells a e
more pronounced, the neutrophiles increase in number. t is possible
that this may be as.sociated with greater activity ol il.e bl.u.d-fornnng
or-ans. Xo\' marked changes were observed in connection with the
number of eosinophiles, only on one day (;}.(;.2.), during the early
stages of the disease, was there what one could descnl)e as an
eosinopliilia.

Morrosrof.ir A\'-mm/zfr/Z/V^».—Signalment : Merino wether in good
condition, having only temi)oroiy teeth.

The mucous membranes of the natural openings weie very pale
and almost dead white in colour. The hlood. was extremel.y watery
barely .staining the fingers, and was of almo.st an amber colour A
.mod quot;deal of fat was present in the fat dejiots. ^o abnornial tluid
was present in the abdominal cavity. The Ijjmphnlir jjlnnds on
.section were pale and moi.st. The pericuirdial sac contained about

20 c.c. of a clear colourless fluid. Tlie liver was slig\'litlj^ enlarged
and firm on palpation. On section a watery fluid escaped from the
cut surface, which was of a mottled appearance, the central portion
of the lobule being brown and opacpie and the periphery almost trans-
liarent and grey in colour. The heart fat was nornml in amount and
appearance. The heart itself appeared quite normal, except that the
myocardium was of a greyish colour and opaque, suggesting degene-
rative changes of a fatty nature. The lungs were extremely pale,
but excepting for a certain amount of emphysema, were not altered
in any way. The kidney had a fair amount of peri(;ai)sular fat, the
capsule stripped easily, the cortex Avas of a yellowish brown colour
and the medulla and boundary zones were extremely pale. The
spleen was decreased in size and measured 7.5 by 5 by 1cm. The
capsule was markedly wrinkled, the trabeculae were distinct, but the
Malpighian bodies were indistinct. The. other organs, such as the
adrenals, thyroid, etc., were all systenuitically examined, but apart
from the fact that they were paler in coh)ur than normal, no abnor-
malities were observed macroscoijically. The contents as well as
the mucous mendir anes of the rumen, rectw.uluni and onuisuni were
normal. In the ahorna.\'iuni nvuuerous wire-worms were present.
The mucous membrane was pale and the contents were li([uid and of
a (lark brownish colour. In the small intestine the ingesta were
li(iuid and of a dark chocolate colour and a few Stronyyloides papil-
losus were ])resent. The faeces in the large intestine wei-e of a dark
colour. Very few adults of Ocsophayostnnunn rohnnbianum were
identified, hut no nodules were present. No changes were recognized
in the bone-marrow.

Anatomical I\'atholnyieol DIaynosis.—Very marked anaemia,
jialeness of all the organs and of the visible and other mucous uuhu-
hranes, throughout tlie body; degenerative changes of the liver,
myocardium and kidneys; emphysenui of tlu\' lung; numerous wire-
woiius; very few nodular worms; few Stronyyloide.\'^ papiUo.^us; com-
])lete abseiK\'c of icteius and haemoglobinuiia.

Aetiolnyiral Diaunosis.—Killed in extremis (jiractically ])uregt;
infecti(m of Havmonrhus contort us).

.Mirros(\'igt;pic IC.ra ml nation : h\'idneys.—There were slight d(»gene-
rative changes of a fatty luiture. Some of the cells, especially of the
convoluted tubules, staiiu\'d a faded orange with Siuian 111, and with
a 4 mm. objective were seen to be distended wit!» tine radiating
cry.stals, wliich staiiu\'d similarly. There was no evidence of any
iron-containing jiignu\'ut in the kidney. No other lesions were present.

Spleen and Ijuny.—Xo changes were seen microscopically, ex-
cept that the lymphoid follicles in the spUM\'n were not well defined,
and emphysema of lungs was present. With sjiecitic staining for
iron, vory little iron-containing pigment c()uld b(gt; identified in the
splecMi and none at all could he recognized in the lungs.

/,irer.—When the haenialum-eosin stained .sections were
examiiuMi with the naked eye by holding them u]) against the light,
a distinct mottled appearance was observed. This was due to some
])ortions .staining slightly or not at all and other staining more
eveidy and more intensely (,see Figs. 1 and 2.) On microscoinc exami-
natioii the slightly .stained or even unstained areas were seen to In^

those situated around tlie central veins. Here the cells contained
large vacuoles, which did not stain at all, but the peripheries of the
cells were well defined as slender pink staining outlines. Many cells
were devoid of a nucleus and in others the nucleus was situated
against the periphery of the cytoplasm, although cells having a more
centrally situated nucleus were also jiresent. Towards the periphery
of the lobule, i.e. around Grlisson\'s caji.sule, the cells wei\'e intact and
normal in appearance. The extent to which the (;ells with these
vacuoles occurred, varied. The greater proportion of some lobules
were so affected, with the result that there remained only a narrow
peripheral portion of the lobule, with more or less normally staining
liver cells.

This vacuolated appearance of the cells was also seen to be
present in van Gieson and Giemsa stained .sections, but with Sudan
III the contents of these cells stained in most cases a faded
orange colour. A large number of cells was distended with fine
radiating cry.stals (see Fig. 3) somewhat like those seen in fat necrosis
(see Fig. 4). These crystals also stained a faded orange colour with
Sudan III. It was only here and there that cells containing true
fat were encountered. The presence of- a very little true fat was
confirmed when sections stained with Xile Blue Suli)hate were
examined. With this stain, some of the cells around the central
veins stained blue and others remained unstained. The cry.stals pre-
viously referred to were for the mo.st part unstained, although some
did stain a light blue. According to Mallory aiul Wiiglit (1922),
such colour reactions are obtained with soaps, fatty acids and li])o-
chromes. The interpretation of these lesions will be fully disinissed
elsewhere. Xo demonstrable iron containing pigment was present
in the liver.

The.se i)eculiarly staining cry.stals wei\'e found in epithelial
cells of nearly all the organs including the lung, thyroid, intestine
and adrenals. In the case of the latter organs only the (tells con-
taining these crystals .stained with Sudan 111. Xo crystals weie,
however, demonstrable in the myocaidium.

Table 2 and graph 2 contain the haeniatological recoi-ds of Sheep
Xo. lliS9(). Infection was commenced on Hi.11,25 at the rate of 201)
larvae every second day until (gt;()() larvae had been given. Thereafter
5,000 larvae were given eveiy second or third day until apjiroxi-
matelv 50,()00 larvae had been given. The last 5,000 larvae were
given\'on 2.\'J. 12.25.

Chdiifjes in the red celln.—Very soon after infection the number
of led cells begins to decrease. This is also reflected as a decrease in
the ])ercentage of haemoglobin and the red i)recii)itate. By 20.11.25
()00 larvae had been administered (200 (m 10/II, 200 on 18/11 and
200 on 20/11). During the following 5 days a remarkable drop of
more than -3 million red (sells jier c.nim. of blood occurred and the
(|uestion which immediately arises here is whether this marked
(lecrease of the number of red cells is or is not entirely due to the
action of the parasites. This is very difUcult to prove, and one

.Method of treatment: Infection com niencetl lO.11.25nbsp;n^ith llaenioiicluis contortiis and

eonfinued ereri/ .terond or third daij iinlil ;quot;)(),()()()nbsp;larvae had heen //iven. Infection
completed hjj 2-i. 12.25. ^

Although infection was commenced on 16/11 ,\'25, the first seven determinations, i.e., up tc and including 2/12/25, arc regarded as normal.
For abbre\\\'iations see Table I.

hesitates to draw that conelusioii, particuhirlv in view of the fact
that infection was coniinenced only 9 days previously. According to
Vegha (1915) the larvae that were administered on IG.11.25 Avould
he on 2o. 11.25. just on the point of undergoing their 4th ecdysis
before entering on the adult .stage. In the same paper Yeglia describes
hlood coagula in the mucous membrane of the alxmiasuin, -3 days after
infection. In the first parasitic .stage of JIaemonchiil larvae, the
mouth parts are not armed with a lancet (which only develops during
the 2nd i)arasitic stage and apparently only conie.s into use in the
adult stage), but the larvae are already able to produce in the 2nd
parasitic .stage, i.e. tlie 4th stage larvae the blood coagula described
by Vegha. It seems, therefore possible, that tliese voung forms can
})roduce changes in the blood, but it is doubtful, if\'this is likely to
occur to the extent of decreasing the red counts bv 3 million i)er c iiim
of blood in 5 da.ys (from 20.11.25-25.f 1.25). That tlie effects\'pro-
duced by them must be regarded as a definite contributory cause of
this is without ([uestion. but a number of other factors may also be
partly responsible for this big decrease in the red counts.\' If the
blood volume had beccmie increased such low counts might have been
obtained. On the other hand, the blood might have\'^beeii undulv
concentrated .m 11.11.25 and on 20.11.25. This could have occurre\'d
under certain ahnormafly dry conditions and high temperatures of the
atmosphere, ()!• if the animal incidentally had a diarrhoea or polyuria.
No observations to obtain information conceining the.se several factor.s
were made at the time. If there was overconcentratitm of the blood
the true counts with a normal blood volume may really have beei\'i
.somewhere in the neighbourhood of 12 million ce\'lls (instead of 1.3 9
million, as actually recorded on 20.11.25). This decrease would then
have been correspondingly less.

From 2.12.25 there is a continuous and luogre.ssive decrea.se in
the number of red cells every week. During the .second week after
the administration of the last dose of 5,000 larvae, there is j)iactically
a coI]a])se of the red count, and this decrease by more than 5 miliion
red cells ])er c.mm. of blood during 9 days time, must be regaided as
phenomenal. It does seem rather jiaradoxical that the\'^aiiaemia
deveh)])s progressively more rai)i(lly when the animal is no longer
lieing infected. It inay of course be that just about this time the
limits of comi)ensation were being reached, and that, if infection had
been continued, a siniilar or even greater collajise would have occurred.
Did this not occur with continuous administration of infective laivae
then it would ai)i)ear that the method of infection employed was
wrcmg. Instead of giving large do.ses at fre(iuent intervals,\'a .single
large dose, or smallei\' doses at greater intervals, should perhajjs luTve
been iven. \\\\ hen larg\'i? doses are g\'ivpii at short intervals disturbances
in the abomasuni niay be brought about, as a result of which a large
])r()portion of the infection may become lost. This may actually be
responsible for the so-called recovery ca.ses.

It will be observed that the jirogressive decrease in the number of
led cells which occurred from 2.12.25 to 23.12.25, is not reflected in
the haemoglobin and percentage volume curves. The haemoglobin
remains more or le.ss .staticmary, but the precijiitate is even somewhat
increa.sed on 23.12.25. If one could at this time have obtained
reliable data of the true average size of the red cells, a .satisfactory

explanation of these results would probably have been obtained
Measurements that were made indicate that there was an increase in\'
the size of the cells, but it is realized, as previously stated that too
few cells were measured in order that reliable coni-lusions could be
drawn in this connection. It is nevertheless of interest to present the
fio-ures that were obtained. These comprise measurements that were
made during- the pre-infection period, and at various intervals during
the course of the disease, 15 cells being nieasurelt;l in various fields in
each case. The results are tabulated below: —

(lunifiex in colour and rolunie indices.—On lefej-ring to Table 2
it will he seen that there is an increase in the volume nidex and m
the colour index, but there is a decrease in the colour volume index
ihese changes in the indices can he caused hv an increa.se in the size
ot the red cells.

On 7.1.20 and 9.1.20 morphological changes, such as anisocvtosis
a sugge.stion of polychroniania and occasional -Tolly bodies were
recorded, but no other evidence of anaemia was found\'on microsconic
examination.

Chantjes in the Lcucoci/te.s.—A leucocvtosis was present on
-0.11.25, i.e. about 9 days after infection was commenced, and a
neutroplule leucocytosis was recorded towards the end of the\'disease.

ill! -^^\'^\'\'\'\'quot;^^\'opic K.raminahou.—This merino ewe lamb died on
ll.l.LO. Ill pre.senting the re.sults of the post-mortem examination, it
is not considered necessary to give a detailed descrijition of all the
oipns examined. Tims reference need oiiiv be made to organs in
which ciianges were recognized.

The blood was coagulated. Tliere was iiiarlxed anaemia witii
paleness of all the organs and of tlie visible ami otiier mucous
membranes. Tliere were degenerative changes in the lieart and the
liver and .slight oedema of the lungs. The aliomasal contents were of
a yeliowisli cliocolatc colour. Wirewornis were exceedingly numerous.
A few nodules of Oesophai/ostomum aduinltianuni were present in tlie
.small inte.stine, hut tiiere were no adult nodular worms. Tiie spleen
showed slight atrojiiiy, measuring 10 iiy 0.5 i)v 1.5 cm. No otiier
parasites were jiresent.

(2)nbsp;Anafoniica/ PathoJofjical J)ia()nosis.— V\\\\U was similar to tiiat
of .sheep 10027, except tiiat no parasites other than Haemonchus
con tort us were recorded.

(3)nbsp;Aetiolof/lcaJ Diagnosis.—Anaemia due to a pure infection of
/laemonclnts contort us.

_ _ (4) Mic, ■oscopw E.ramination.—The lesions in all the organs were
similar to those described for Sheep No. 10027, except in tiie case of
the liver. In this organ the orderly arrangement of the cells around

tlie central veins was disturbed. The nuclei of these cells were
pycnotic, and in some cases absent altogether. The cytoplasm of the
cells stained more intensively with haemalunieosiii than that of
normal cells. Ihese changes m the cytoplasm and the nuclei of the
cells immediately around the central veins, were interpreted as early
stages of necrosis. (Inly occasional cells some of which contained
crystals similar to those previously de.scribed stained with Sudan III
Ihe staining rea(-tions were otherwise .similar to those described for
biieej) Ao. 1()02(.

larvae had been administered. Jn the beginninquot;- each dose
consisted of 200 larvae. The last of such .loses wi^s given on
..(».11.20. llt;roiu 2.12.2;) each dose consisted of 2.()()() larvae. On
23.12.25 infection was completed.

C/unifje.\'lt; in the red (•(■//•v.—During the pre-infection period there
IS a certain amount of what is interpreted as normal variations\'in the
red c()unts and other determinations that were made. Durin«- the
infection ])enod. there is even greater fluctuation iu the countsquot;^etc
but during this time there is a tendency towards an increase in the
red counts, accoinjianied by a Corresponding increase in the amount
of haemoglobin and in the jiercentage volume of red cdls. One is
very much tenijited to ex])lain this as being due to increased activity
on the i)art of the blood-fonning organs, as a direct result of the
action of the iiarasites. Xo demonstrable evidence of such activity
could, however, be found when making careful microsco])ic examina-
tions of stained smears during this time.

It is again somewhat significant that, within 14 days after infec-
tion was completed, the ])i\'()gi\'essive decrease in the number of red
(•ells commenced, and again tlie remarkable decrease of 5 million red
Cells ])er c.mm. of blood was registered within a ])eri()d of ,S days.
The i)eicentage of haemoglobin is the lowest, and the iiercentage
volume of red cells least, on the 3rd and 5tli of February, 192(). (hi
these dates, however, there is a slight increase in tlie red counts.
There are (|uite a number of factors that may be responsible for this:
H) Krror in counting; this is i)ossib]e. andquot; it is generally admitted
that one of the most freciuent sources of error in liaematological work
is in connection with the counting of the red cells. (2) I\'oikilocytosis
and anisocytosis was of an extreme degree on these dates; niicrocytes
were very numerous; macrocytes were less fre.pient. The anisocytosis
is well siiown in Fig. (» (from smears made on 21.1.2(1), and should he
compaied with (he normal cells of more or less uniform size, as seen
in Fig. 5 (from smears made on 3.12.25). Fig. (J is a uiicroi)hotograigt;h
of cells from smears made on 21.1.2(!. when the red counts fell from
10.3 million of the i)revious week to 5.5 million i)ei\' (•.mm. of blood.
The values obtained when measuring 15 cells from smears made oii
3.12.25 are: 34.5, 33.5, ;;3.5, 31.(1, 32.(1, 34.5, 33.5, 315 34 0
31.5. 32.5, .\'Ui.O. 31.0, 32.5, 33.0, when the quot; Okular Schrauluunnikrol
meter,quot;\' liaving a (j com]), ocular, with a 2 mm. aj)ocliromatic objccfivo

Method of treatment: Infection «\'/f/; Haeiuonclius coiitortus commenced on 1(5.11.25 and

/•/i gt;1 /» u/jfy^/fnbsp;^ v. 4-1, ^ „..1nbsp;......j..\'7 t\'i/\'inbsp;7nbsp;iiinbsp;•

Viscosity from 30/12 ;25-10/2/26, was determined at the following temperatures : 30, 31, 31, 30, 28, 26, 30, 28, 28, 30, 30, 30.
An average of the first five determinations is regarded as normal for this sheep for calculating the colour and volume colour indices.
For abbreviations, see Table 1.

is used, the above results must be multiplied by .14. in order to
convert them into values of microns. All the meaurable cells in a
field were measured as they were encountered. The values are fairly
uniform. The .smallest cell measured 4.3/., the largest 5/x and the
average was 4.G/t.

On 21.1.26, when without measuring any cells ani.socytosis could
with ease be diagno.sed microscopically from stained smears, similar
measurements were made. The values are: 28.0. 41.5 -30 5 \'^8 5
27.0, 37.0, 31.0, 28.0, 40.0, 30.0, 40.0, 41.0, 33.5, 31.0, 36.0.quot; ^The
smallest cell measured 3.8/., the largest 0.8u and the average w-as
4.5/x. The variation in .size is considerable.

The changes in the shape of the cells (poikilocytosis) towards the
end of the disease wei-e of a most varied nature. This is well
illustrated in the niicrophotographs Figs. 7 and 8. It is not possible
to describe all the various shapes seen, but those poildlocytes more
commonly encounteerd were of the shape of a pear, half-moon, bell,
tennis racket, or a comma, etc. Many cells .stained less intensively than
others and in numerous cells are central clear areas which did not
stain at all, the so-called quot; ghisskorper quot; and quot; i)essarformen.quot;
referred to by Schilling (1922). If one can draw any conclusions
from the morphological study of stained smears, these cells are clearly
deficient in haemoglobin, and this would explain a decrease in the
haemoglobin content when no corresixniding decrea.se occurred in the
number of red cells. In other words one would expect a lower colour
index than normal, and this is actually the ca.se (see Table 3). If
however, the possibility of an error in counting be admitted, such a
minus colour index will also be (takndated when the counts reveal
more cells than are actually present hut when the haemoglobin
determinations have been correct.

A deci\'ease in the precipitate without a corresponding deci\'ease in
the number of red cells (\'an occur when the red cells are decreased in
size. On account of the exti\'eme poikilocytosis that was present, it
was useless to measure the cells, as the hgiires obtained would
obviously have been unreliably;. It can neveitbele.ss lie stated with
confide uce that a lurg\'e number of microcvtes were present.

In these smears there were not infreciuently very small cells, but
owing to the very marked anisocytosis and jwikilocytosis it is not
(juite clear if these aj\'e also to be legaided as microcvtes oi\' whether
they are perha])s haemoglo])in fragments, the so-called scliistocytes of
Ehrlich. quoted by Ki\'umbhaar (1!J28). or the quot; ,scliizolt;\'vten riW\'eried
to hy Naegeli (1912). According to this authoi\'. these cells do not
occur in the bonemarrow, l)ut only in the peripheral blood and may
develop with di.sturbances in isotonicity, chieflv when cells of small
resistance are produced in the boneinarrow.quot; If such cells weie
counted as individual red cells, this w(mld tend to ])roduce abnor-
mally high red counts.

Tust before death there was an appai\'ent slight improvement in
the anaemia. Morphologically there was no evilt;lence that increased
regenerative changes in the haeiiiaiioetic organs was resnonsible for
this. This w-as probably due to an increased concentration of the
blood as a result of diarrhoea, serous atrophy of the fat. hydroperi-
cardium and disturbances in the appetite an\\l the amount t)f water

ingested. It is a pity that absolute blood volume determinations were
not made at this time. If this had been done, a decrease in tlie total
blood volume Avould probably have been found to be present.

Changes in Viscosityis a decided decrease in the visco-
sity on 21.1.26, when a very marked decrease in the number of red
cells occurred, but slight (dianges in the number of red cells were not
reflected in the viscosity curve.

Macroscopic Ed-amination.—Tliis sheeu died on 11.2.26. The
post-mortem findings were somewhat different to those recorded in
previous cases, in that the condition of this ewe lamb was poor, there
Avas marlved serous atrophy of the fat and a well marked hydroi)eri-
cardium was present. Except for these changes, the naked eye
appearances were like those previously lecorded, such as pale mucous
membranes, absence of icterus, clear urine, pale and watery blood,
and degenerative changes in the parenchymatous organs. No para-
sites other than Haenionchn.\'i conforfvs were present.

Microscopic 7^.raniination .—The lesions are very similar to those
described for Sheep Nos. 16027 and 11896. Cells\'stainino- a faded
orange colour with Sudan III were found in all the organs except the
heart. As the lesions of the liver resemble those in Sheep Xos. 16027
and 11896 (tombined, it is necessary to give a little more detailed
description of the microscoi)ic appearance. There are in the
haemohini-eosin stained sections numerous cells with vacuoles around
the central veins. These cells stained a faded orange colour with
Sudan 111 and the crystals previously described are present in many
of them. S(;attered almost irregularly throughout tlie substance of
tlie hver are fairly large areas, up to 11,gt; in cross-measurement.
In these are cells containing globules staining a lemon yellow colour
Avitli Sudan III. No crystals are present in the centrarcells of these
lesions, but cells staining the chara(;teristic faded orange colour and
containing crystals are present towards the periphery. The lesions
are usually situated in the immediate vicinity of the central veins,
hut sometimes they occupy variable i)ositions \'in the substance of the
lobule. It is not quite clear whether these are to be regarded as an
intermediate or a further advanced stage in the development of the
lesions In (piite a number of cases the nuclei of the cells around the
central veins are pycnotic and these changes are interpreted as early
stages of necrobiosis.

^ contain the haemotological records of Sheep No.
and Sheep N«. 22388.:respectively. Infection with Ilaemonchvs
contortn.^ larvae wa.-j commenced on 5.6.29. Small doses were given
until infection was completed towards the end of .Tune, 1929\' In
these two .sheep exact details as to the approximate number of quot;larvae
administered are not available.

Table 4.
SHEEP No. 22387.
Method of treatment: Infected icifh Hueiiioiiclui.s contoitusnbsp;//\'07» 5.C.29.

Determinations on 29/4/29, 10/5/29, and 5/6/29, are regarded as normal for calculating the Volume and Colour indices.
For abbreviations, see Table I.

		W3

		o


	00	o
		u
	5-1	ac	n
	6	^	u a
		O
lt;		u	i
	W		oquot; C-l
	M
	OQ	0)

Changes the Red Cells.—Witliiu a week after infection tliere
is a slight rise in tlie red counts and in tlie liaeinoglobin content. A
coriesponding increase in the percentage volume ot red cells does not
occur. This is possinly merely the normal variation that occurred in
the number of red cells and is prooaoly not due to increased activity
on Tlie part of the blood-tornung organs. Thereafter a progressive
decrease in tlie number of red cells and the total haemoglobin coutent
takes place until 8.7.29, i.e. two days before death, when the red cells
were millions and the liaemoglohin 24 per cent. A corresponding
and progressive decrease also occurs in the percentage volume of red
cells until 1.7.29; after this, instead of further decreasing, as might
perhaps be exjjected, the precipitate remains constant until (J.7.29
and frcmi this date until 8.7.29, i.e. in two days time, the precipitate
a(;tually increases from 15 ])er cent, on the two previous occasions to
19 per cent. The effects of these changes on the colour, the volume
and the volume colour (saturation) indices, will l)e fully discussed
subsequently.

Morphological Changes in the Red CV//a-.—Smears stained
according to rappenheim\'s May Griinwald-Giemsa method, were
carefully examined microscopically. On 1.7.29 the first evidence of
anaemia was observed. This consisted in changes such as anisocy-
tosis, slight polychromasia and occasional punctate baso^jhilia. Pre-
vious to this occasional very large red cells were observed, but to such
no i)athological significance was attributed. During the further
course of the disease, these changes became progressively worse and
towards the end of the disease (0.7.29), the anisocytosis, polychro-
masia and punctate basophilia were very marked. In addiiton,
I)()ikilo(,-ytosis and not infrequent Jolly bodies were present, but the
poikilocytosis was not of the extreme degree described for Sheep
No. 11921.

.Many of the cells in the smears made during the later stages of
the disease stained less intensely than normal, and in quite a°larlt;\'\'e
number there were central clear areas which did not stain at afl.
These morphlt;)h)gical changes indicate that the cells are deficient in
liaemoglohin. On 8.7.29, two days\' before the animal died, similar
changes were i)resent, but the.se were, if anything, of a more severe
degree.

Change.^ in Size of the h\'cd C —Aleasurements were made (20
(•ells) during the pre-infection period (29.4.29), and again (20 cells)
when the disease was at its height ((gt;.7.29), and a third time (40 cells)
two days before the animal died (8.7.29). These results are tabulated
below : —

Dale. Sniallcsl Cell. Lanjest Cell. Average
29.4.29nbsp;3.3/xnbsp;5.7/.nbsp;4.2/1

The changes in size which the.se measurements suggest will be
much better appreciated by referring tol Figs. 11, 12 and 13 which
are microphotographs taken on the same day with the same malt;gt;\'ni-
fication, of smears made from this animal during the l)re-infection
penod (29.4.29) and later on when the anaeniia was well established
(G.7.29).

Chan(jcs in the Colour, Volume, and Volume Colour Indirex.—
The change,s in iliese indices in this particuhir case are very interest-
ing. In cah\'ulating the various indices in the linnian sullject, it is
usual to regard 5 million cells pei\' c.mm. of hlood as heing eiiual to
100 per cent., the anumnt of haemoglobin contained in 5 million red
cells per c.mm. of blood as repre.senting 100 ])er cent., and tlie volume
of ])acked red cells (precipitate) obtained by centi\'ifuging a blood
containing 5 million red cells jier c.mm. at cei\'tain definite speeds, un-
til such time as constant readings are obtained, as repi\'esenting 100 ])er
cent. Tliere seems to be very little agreement as to what this last
figure should actually be. l{o,ssdale (192;{) showed that anticoagulants
materially affect the centrifuge readings. The values obtained by the
various authors quoted by Eossdale are: Hedin (1889) 51.(1, using
^fiillei\'s fluid as anticoagulant and centrifuging for .5-7 miiuites at a
.sj)eed of 8,000 revolutions pei\' minute; Daland (1891) 51.8, usino\'2.5
per cent, bichromate solution as anticoagulant and centrifugin«\'«\' for
3-(i minutes at a s])eed of 10,000 revolutions ])ei\' minute, with red
count of 5.07 million i)er c_.mm.; Caijjis (1903) 51.5, using whole blood
and centrifuging for 3 minutes at a speed of 10,()()() I\'evolutions jiei\'
minute, with red counts (in males) of 5.00 million i)er c.mm • Il-irvev
(1919), average 46.5; (Iroen (1921), 51.4-55.1 (for males). quot;

Eossdale (1923) himself found an aveiage of 50, when centri-
fuging for 20 minutes, at a speed of 3,000 revolutions ])er minute.
Haden (1925) used sodium oxalate at anticoagulant and centiifuyed

the Woo.l lor -JO minutes at 2,500 revolutions per minute, as suggested
by Hooper, Smith, Belt, and Whipple (1920). His figure is lo for
a bloo.l containing o million cells. In calculating the various colour
and volunie indices, this author regards the average normal per-
centage volume of red cells at 46, which would represent 100 per cent.
Whatever hgure i_s agreed upon as a result of examining a laro-e
uumber of normal individuals as being the normal average for the
human subject that figure may differ considerably from the normal
of any pai^icular patient. When one is working with animals under
expeiimeiitally controlled conditions, it is unnecessary to take as
normal, the standards as laid down by various authors for particular
species it IS niuch more accurate to lay down the normal for each
indiyidual during the pre-infection period. As there is a normal
variation in the counts of each individual, one should make at least
0 determinations during the pre-infection i)eriod on different days
lliis Avas not always possible, and in some cases values obtained after
infection was commenced were considered as normal. This was as a
rule only done when no changes had occurred, which could be re-
garded as other than the normal variation. With this method,
which can obviously be applied to the human subject on raie occa-
sions only, more reliable colour and volume indices can be calculated.

When the colour index, the volume index (Capps), and the
vo unie colour index (Neser 1921 Kossdale 192;5) or the\'saturation
index (Haden 192o) are calculated, when 5 million cells per c mm of
blood are regarded as 100 )er cent, and when the haemoglobin con-
tained in such blood as well as the precipitate obtained from it under
the conditions previously stated are regarded as 100 per (!ent then
111 normal individuals these indices should always be 1 within
admissable limits of technical error and within thequot;limits of m)rmal
variation in an individual, that is, if normality for each individual
IS hr.s-t of all established as advocated in this work. In this work it
was not possible to investigate what variation, if any, may occur in
sheep or in an in.hvidiial sheep, dependent on changes in size and
iiaemoglobin content of the red cells when technical errors have heen
eliminated by making in each case a number of che(dv counts.

There are undoubtedly tremendous differences in the red counts
of apparently normal sheep. Ccmnts ranging between 10 and 14
inilhon per c.mm. of blood are ouite common, i.e. for well-grown
lamlis up to a year old. One woubl, however, exjiect that as the red
counts become inc.reased or decreased in normal sheej), the haemo-
globin content and the percentage volume should show .-orres-
ponding variations, .s^o that the various colour and volume indices
will remain unaltered, except where the cells may be increased or
decreased 111 size and contain a ])rop()rtionately increased or decreased
amount of haemoglobin.

Blood containing a normal number of cells with mic^roisytes nre-
donnnating wil give a relatively small precipitate and the\' volume
index will be decreased, but on the other hand if mac,rocvtes pre-
dominate blood with a normal number of cells will give a relatively
large precipitate and the volume index will be increased. In normal
individual sheep, such a deviation from the normal volume index
(which IS 1) may occur, if one uses the average obtained of a laro-e

number of determinations on normal sheep as the normal for this
species, but should not occur when the nornuility of the individual
which is being examined has been determined and is being used.

The colour index is the relative ratio of the haemoglobin to the
number of red cells; the volume index (Capps) is the relative ratio
of the percentage volume of red cells (more conveniently termed the
precipitate), to the nund)er of red cells; the volume colour index
(Neser and Eossdale) or the saturation iiulex (Haden) is the relative
ratio of the Tiaemoglobin to the percentage volume of red\'cells. These
can be simply calculated in the following way: —

100 X artudi Jiaeniof/Iohiii ^ avercifjc novnuil red eotnd
averofje nonnaJ /uieiiiof/lohin (ictudJ red co?/f x 100

100 x actnal haenw(jlohin ^ average normal precipitate
average normal haenwgJohin actual precipitate x 100

AV^hei\'e the average nornuil red count, haenu)gh)bih percentage and
precipitate of an iiulividual cannot be i)reviously detei\'inined, the
average nornuil for the species (;an be sid)stituted.

The i)ai)ers on the volume index by Capps (1903), Wroth (1907),
and Larrabee (1911), quoted by Iladen (1925), were unfortunately
not available to me.

The term quot; volume colour quot; was used by Neser (1921) to express
the ratio of the haemoglobin ])er(;entage to the percentage volume of
red cells. TTnfoi\'tunately Xeser did not calculate the relative ratio,
but made a direct calculation instead, sim])ly by dividing the i)reci-
pitate into the haemoglobin-percentage. His index in normal horses
could, tlierefoi\'e, luiver be 1. Previous to this Herz (1S93), (quoted
by Rossdale (1923) and Iladen (1925), calculated tiiis index iu
exactly the same way and called it the quot; s])ecifi(r haemoglobin con-
tent of the cell quot; (Si)ecifisc.her ITaenu)globin gehalt). In the case of
a nornuil liunian blood having a haemoglobin of 100 ])er cent, and a
red precipitate of 50, Herz\'s index would be 100/50.

Kossdale (1923) independently used the term volume colour index
to express quot; the capacity of the cell volume for haemoglobin.quot;
Iladen (1925) suggested for exactly the same thingquot; the term satura-
tion index. Both these latter workers give values wliich are exjiressed
in terms of the normal. Consequently all these indices should be 1
in the case of normal adult individuals, and where they are either
greater or less than 1, a deviation from the normal is indicated, ])ar-
ticularly changes in the haemoglobin content of the cells and changes
in the size of the cells.

On referring to Table fV, it will be seen that definite changes
occurred in the (iolour index, the volume index, and the volume cohTur

index. Any (tlianges occurring in these indices np to and including
the 21.().29 are probably due to technical errors, particularly in the
counting of the red cells.

Changes in. the Colour Index.—Towards the later stages of the
disease there is a tendency to a slight increase in this index. Haden
(1925) states that a colour index greater than 1.00 means only that
the (!ells are larger than normal. Theoretically, a plus colour index
would indicate either an increase in the haemoglobin content or a
decrease in the number of red cells, if these are larger than normal;
Imt in the latter case the larger and fewer cells must contain the
same amount of haemoglobin as the greater number of smaller cells.
There is, however, definite evidence, on morphological grounds, that
the cells are to some extent deficient in haemoglobin; such deficiency
would therefore tend to correct the tendency towards a plus colour
index; in other words, one may actually be dealing with a patho-
logical blood (;ontaining less, hut largerquot; cells than normal, and the
colour index can remain 1.00, if there is a corresponding decrease
in the amount of haemoglobin in the cells. There is very little
doubt that this had occurred in this particular sheep (No. \'22387).
Notwithstanding, there is a slight increase in this index and one
mu.st conclude that the increa.se whi(;h occurred in the size of the
cells was of su(;h a degree, that it produ(!ed a plus colour index, even
though the cells Avere deficient in haemoglobin.

Changes in the Volume Colour Inde.r.—This index remained
normal up to 1.7.29, but it was markedly decreased on 0.7.29 (5 days
later), namely to .09, and a further decrease took )lace on 8.7.29 (2
days later) when it was .53. A decrease in the volume colour index
can occur if there is a relative deficiency in the haemoglobin c(mtent
of the cells, when the cells remain the same in size and nund)er, oi\'
if the cells are decreased in number even though they may be increased
in size. When, liowever, the larger hut fewer cells are fully charged
with haemoglobin, the volume colour index may remain unaltered.
Theoretically, a decrease in the volume colour index can aLso occur
if the prec.ipitate is increased when the total haemoglobin remains
unaltered. The precipitate can increa.se if thei\'e are more cells, which
are at any rate not decreased in size, or if the cells nornnd in number
are increased in size; hut in both these cases the volume cohmr index
will remain unchanged if the cells, whether they are normal oi\'
increased in size, are fully charged with haenu)globin. ft is, there-
fore, obvious that when the volume colour index is decreased, the
cells mn.st be deficient in haemoglobin. As already stated,\' the
preseiK-e of this deficiency was .suggested by the morphological changes
described and also by the changes in the colour index, although, ad-
mittedly, the plus colour index emphasizes rather more the increa.se
in the size of the red cells.

Changes in the Volume Inde.v.—Apart from slight change.s,
probably due to technical arrors, no changes occur in the volume
index up to and including 26.0.29. On 10.(gt;.29, however, there is a
decided decrease in the volnme index. This occurs within a week after
infection was commenced. This was unfortunately not observed at
the time and conselt;iuently the determinations could not be repeated

in order definitely to eliminate the jjossibility of a technical error
dur ingquot; centrifug\'ing\'. C)n 1.7.29 the volume index begins to increase
and is decidedly increased ou (gt;.7.29, namely to 1.(5. It is even further
increased 2 days later, i.e. on 8.7.29, when it is 2.14. This indicates
very definitely that a marked increase in the size of the red cells has
taken place. This was already suggested on general morphological
grounds, and also by the measurements that were made, e.g. f the
average normal size of the red cells was 4.2/x during the i)re-infection
period, but towards the end of the disease (ou (gt;.7.29 and 8.7 29)
the average diameter of the red cells was 5.4/x_ and 5.5/x respectiveTy.
Slight differences in size, especially when uniform, may be difficult
or impossible to appreciate microscopically, even by actually measur-
ing^ the cells, l)ut^mu.st nevertheless cause a well marked increase
in \'the precipitate,quot; with a conseiiueiit plus volume index. This is
commonly encountered in early cases of pernicious anaemia in the
human subject.

From a purely ]iaemotoh)gical point of view, the outstandiiKquot;
features of this jiartumlar case are : mark\'ed morjjhological evidence
of anaemia, e.g., anisocytosis, poikilocytosis, polycJiromasia quot; quot;\'lass
kori)er quot; and quot; pes.sai\'formen,quot; punctate l)a,so})liilquot;ia, and Jollv h(7d\'ies
There is a slight increase in the colour index, a marked decrease in tlie
volume colour or saturation index, and a marked increase in tlie
volume index. These changes are interi)reted as indicating that there
is a relative deficiency in haemoglobin in the cells and that there is a
marked increase in the size of the cells. Some of the macrocvtes cai
appropriately be classified as megalocytes, but no megaloblasts, so
characteristic of pernicious anaemia in the human subject, were recoquot;\'-
nized. Excej)! for the absence of these last-named \'cells, the blood\'
changes recorded in this particular animal, affetited w\'itli a ])ure
haemonchosis, correspond very closely with those described for
jiernicious anaemia in tlie human subject. Haden\'s (1925) avera\'gt;e
for 50 cases of pernicious anaemia is\': Volume index f.^l\' colour
index f.29, saturaticm index .92. His highe.st volume index is 1 77
witli a saturation index of .5;{. This corres])()nds very closelv with
the indices of Sheep No. 22387, but the colour index\'in periiicious
anaemia seem in general to be slightly higher.

with a neutrophilia on 29.4.29. This occurs during the pre-infection
period and no explanation of the cause of this can be quot;iven \\s
occurs in other ca.ses, there is a leucocytosis with a neutrophilia
towards the end of the disea.se.

The animal which was a young .slieep and had not yet shed anv of
its temporary or milk teeth, died on 10.7.29, when \'a post-mortem
examination was made. The same general changes as described for
previous cases were recorded. There was in addition a very interest!no-
lesion which involved mainly the apex of the heart. \' There was
thrombosis or embolism of one of the branches of n coronary arterV
resulting in infarction of the myocardium in the region of the ai)ex\'
A .similar lesion was encountered in some of the other sheep withquot;
haemonchosis and this will be referred to again later on

Tliis animal must liave died during the early part of the evening
of 9.7.29, and was available for post-mortem examination only on the
morning of 10.7.29, when a certain amount of autolysis and decompo-
sition had unfortunately already occurred, particularly in the liver.
In these circumstances it is not\'^possible to make a definite statement
in regard to specific lesions, but the outstanding features of the
macroscopic and microscopic examinations are: absence of demon-
strable iron i)igment from all the organs, including even the spleen,
which was markedly atrophied, being of small size and having a very
much wrinkled capsule. There was general paleness of the visible
and other mucous membranes, and of the tis.sues in general. There
was no icterus. Microscopically the bonemarrow was found to con-
tain the usual immature forms of granulocytes and erythrocytes, such
as myeloblasts and myelocytes, etc. The presence of these\' cells was
interpreted as indicating an actively functioning bonemarrow. In
the fatty bonemarrow were seen scattered groups or islands of cells,
many of which neutrophile and eosinophile myelocytes, and others
were erythrobla.sts and normoblasts. This was interpreted as a com-
pensatory myeloid hyperplasia involving the fatty bonemarrow. No
parasites other than wireworms were found to he present.

Changes in the Red Cells.—On studying Table 5, with its
corresponding graph, it will be observed that there is during the pre-
infection period a peculiar decrease in the red counts and the absolute
haemoglobin content of the cells, as well as in the precipitate. The
cause of this is not definitely known, hut may possibly be associated
with the artificial conditions under which these animals were placed,
when they were drafted into this expei\'iment. As previously
explained, these animals were obtained from a Karroo farm, where
the conditions for parasitic life are generally unfavourable, (bi
arrival at the Onderstepoort Laboratory, they were immediately
placed in a loose box measuring 0.25 by 3 metres. This box was sub-
divided hy 5 i)artitions into oblong compartments in each of which
were placed 2 to 3 .sheep. The sheep had a liberal .supply of good
food and abundant water, but obviously exercise was restricted to an
absolute minimum. Neser (1923) show-ed that a remarkable increase
in the number and in the percentage volume of I\'ed cells takes place
with exercise or work in horses. No observations of this nature have
so far been attempted on sheep under experimentally controlled con-
ditions, but there is just a possibility that this may he the exphuuition
of the marked decrease in the number of red cells that occurred in this
sheep. Arguing hy analogy, this should not he the case, as Ne.ser has
shown that in horses the reverse process, that is, decrease of the red
cells with idleness and restricted exercise is slow. This may, how-
ever, not he the case with sheep. It is noteworthy that a similar
decrease in the red cells of Sheep No. 22387 (see Tabl\'e 4 and Graph 4)
was recorded. This animal was bought from the same Karroo farm,
arrived here at the same time and was further treated in exactly the
same way as was Sheep No. 22388. This suggests that exercise will
have the same interesting effects on the red cells of sheep as was shown
to he the case in horses by Neser and in cattle by Canham (1930).

If restricted exercise was responsible for the decrease in the
number of red cells and the corresponding decrease in the haemoglobin
content and the percentage volume of red cells, it is difficult to say
whether the blood reached its normal level for conditions of complete
inactivity on 5.G.29 (see Graph 5) or whether the downward trend of
the curve was checked as from 5.().29 when infection was commenced
as a direct result of the action of Haemonclms larvae in producing an
initial stimulating effect on tlie blood-forming organs.

From 17.0 29 luitil G.7.29, there is a progressive decrease in the
number of red cells, together with a decrease in the amount of
haemogfobin and in the pricipitate. The rate of decrease in the red
cells varies from 1..5 to 2.5 millions per week. The course of the
disease in this sheep as well as in Sheep No. 22387 can be regarded as
acute or even pera(;ute, as it is not often that sheep will die under
artificia_l conditions of infection, from a pure floemonchvs infestation
within 5 weeks after infection was commenced.

On 8.7.29 the red count and the precipitate remain practically
the same but there is a decrease in the haemoglobin content as coni-
l)are(l witli tlie ngures obtained on (».7.29.

Clunifjes ill the colour, volume, and volume colour indices —The
hgures ol)taiiied during the pre-infection period, i.e on \'^9 4\'gt;9 -uid
10.5.29, were regarded as abnormal, consequently they were reiected
when calculating the averag^ normal, red count, haemoglobin
r/\'on \' f I»\'elt;^ipitate. The average of the figures obtained on
o.().29 (blood drawn on this date can also be regarded as liavin«- been
collected during the pre-infecti(m period) 10.(i.29, and 17.G 25) was
regarded as the average normal for this slieej).

Changex in the colour inde.r.—Xo marked changes occur in this
index. In the early stages of the anaemia there is a tendency towards
a decrease in this index, which is calculated as .88 on 2G.G.29quot;. Within
a week after this there is a ])lus colour index and towanir\'the end of
the disease the index again decreases. A decrease in the colour index
IS due either to a deficiency in haemoglobin, or, if the cells are fully
charged with haenioghibin, to a decrease in the .size of the red cells
which means that there mu.st be a relatively greater number of these
smaller cells in order to supply the mn-mal amount of haemoquot;\'lobin
that IS, assuming that supersaturation of the cells with haemolt;vlobii\'i
did not occur, ft is diflicult to measure directly a decrease ?n the
haemoglobin content of the cells, but morphological evidence of
anaemia, such as anisocytosis and punctate baso])hilia was alrculv
present on 2G.G.29. The other factor, namely the de\'crea.se in\'the
size of the red cells, can be determined by direct measurement
Fifteen cells were measured on two occasicms (10.5.29 and 5.G.29)\'
when the animal\'s blood can be regarded as normal, 15 cells w\'ere
measured during the early stages of the anaemia (2G.G.29), and 40
cells were measured when the animal had developed a severe delt;gt;Tee
of anaemia. The.se results are tabulated below:__quot;

Date.	Smallest eell
10.5.29 ......	.\'{.8/t
5.G.29 ......	4.1/x
2G.G.29 ......	.3.5/^
1.7.29 ......	4.1/z
	45

It must agaiu be empliasizerl tliat too few cells were measured to
regard the averages obtained as even approximately true for the
smears of that particular date, but the measurements suggest that no
decrease in size has occurred. According to these measurements no
changes in the .size of the red cells occur up to and including 20.0.29.
The decreased colour index that is present ou this date would, there-
fore, appear to be due to a relative deficiency in haemoglobin. On
1.7.29 there is definite evidence that the cells have increased in size
and this is resi)onsible for the plus colour index on that date. The
more or less normal colour index on G.7.29 is probably due to a
relatively greater deficiency in haemoglobin, in spite of the increase
in size which is probably .still present, as the volume indices on
1.7.29 und ().7.29 are practically the same. Owing to the severe degree
of poikilocytosis, it was useless measuring the cells on the latter date,
as too great a selection would have had to he practised in picking out
the measurable cells. On 8.7.29 the colour index is again decreased
and is practically the same as on 2().().29.

Chaiif/es in the volume index.—One is probably not justified in
interpreting the slight decrea.se in the volume index on 17.(i.29,
21.G.29, and 2G.G.29 as being of pathological significance. A plus
vohune index is pre.sent on 1.7.29 and G.7.29, and this indicates that
an increase in the size of the red cells has occ.urred on these dates.
The measurements previously quoted tend to (ronfirm this.

Changes in the volume colour index.—No marked changes occur
in this index. There is a slight decrease on 2().().29, when the colour
index also is decreased and this tends to confirm the conclusion that
a relative deficiency in haemogiohin was present ou tliis date. Towards
the end of the disease there is a slight tendency towards a decrease
in this index.

Changes in the leucocytes.—During tlie i)re-infection and ])ost-
infection periods, there is a good deal of fluctuatitm in the total white
counts, but there is a tendency throughout the entire course of the
disease towards a gradual rise in the total number of leucocytes. On
referring to the differential counts, it will be seen that thi.s iiu;rease
in the lunnber of leucocytes is due to an increase in the number of
neutro])hiles, and this commences at the same time, as the, so to
speak, pathological decrease in the number of red cells occurs. This
continuous increase in the number of neutrophil\'s is interi-ui»ted on
1.7.29, when these cells decrease frtmi 44 per cent, to ;{4 i)ei\' cent.
It was not possible to determine whethei\' this has any sjiecial patho-
logical significance. On the other hand, the neuti()i)hilia indicates a
healthy activity (m the part of the blood-forming organs, undoubtedly
stimulated thereto as the result of the lo.ss of red cells.

The animal died during the night ot 9.7.29 and was available for
po.st-mortem examination on 10.7.29. It is unnecesaiy to give a
detailed description of all the organs, reference will only be made to
outstanding features of this case : There was very marked paleness
of the visible and other mucous membranes, as well as of all the
tissues throughout the body. The blood was watery and stained

badly, ihe aiiiiiial was in poor condition. There was very marked
atrophy ot the spleen, hydropericardium, oedema of the luno-g
absence of icterus and haemoglobinuria, and what were interpret^\'ed
macroscopically as degenerative changes in the parenchymatous
organs. .Numerous wireworms were present in the abomasum the
inucous membrane of which contained numerous dark red spots \' The
ingesta of the abomasum and of portions of the small intestine were of
a chocolate colour and strongly positive for haemoglobin when tested
(diemicaily with guiacoinc acid. Xo other parasites besides wire-
wonnswere touiid to be present.

i]ficroxcoi)ic c.ramiiuitioii .—lAverThe cells around the central
veins stain less intensely and contain a fair amount of true fat in the
form of small drojilets, otherwise no changes are present and the
crystals described in other cases cannot be identified Kidneys •
Slight fatty changes are the only lesions identified. Bonenian ow In

case ot l)()tfi tiie red and the yellow marrow the i)icture is the
B as described for Sheep Xo. 22.\'{8T.

(^lite a number of cases were encountered in which the infective
larvae that were administered developed to maturity and siibseciuentlv
passed eggs (found in the faeces), without producing any noticeable
effects on the hosts. The nature of this immunity or resistance \'was
not studied.nbsp;\'

A number of other sheep developed varying degrees of anaemia
and then recovered, with a gradual improvement of the anaemia
These can conveniently be referred to as recovery cases. Of (uiite a
number of such cases encountered during the Course of this investio-i\'.
tion. the haematological details of three wil be presented. These
are Slieej) Xo. lotifM) (Table (t and (Iraph (i). Sheep Xo. I!)()80 (T-ibl^
7 and (haj.h 7) and Sheep Xo. 1182S (Table 8 and (iraph 8).

Sheep Xo. l\')()!)9 was infected with ()()() hnvae, which were
given in one do.se on 17.11.2(i. As will be seen on referring to Table
(i and (Tvaj)!! (I, this animal was not examined haematologic;rilv durinlt;gt;\'
the ])re-infeet ion period. The first counts, made 1() days after
infection, are extremely high even for a young sheej). it cannot be
stated ])ositively that, on the day (27.11.20) when these counts were
made, conditions such as jiolyuria, diarrhoea, lack of water, etc
which })roduce overconcentration of the blood, were absent. \' As -i
veult of the infestation, the red counts decreased rapidly until
22.12.20. This was accompanied by a corresponding decrease in the
haemoglobin and the i)i\'ecii)itate. After this date there is a gradual
improvement in the anaemia. The helminthological records\'^of this
sheep are unfortunately not available, so that it is not possible to
state definitely whether the animal continued to pass eggs in its
faeces after 22.]2.2() when recovery lt;\'()ninienced. If oneTan draw
any conclusions from the .study of (xraph (I, it would seem that the
animal had not entirely lost its infection and that during the jieriod
from 7.1.27 to 11.1.27, the parasites again i)roduced a decrea.se in the
number of red cells, with a corresponding decrease in the haemo-
globin and the jiercentage volume of red cells. Thereafter the bloo(l
again improved, until 10.2.27, when a second setback occurred. After
that the animal made an uneventful recovery.

Method of treatment: Infected with Haeinonclms coiitortus, 3,000 larvae, on 17.11.26.

In calculating the volume index the average of the last fi counts is regarded as normal.
For abbreviations, see Table 1.

heieafter 2,000 larvae were given every second, third or fourth .ky
until infection Avas completed on 23.12.25.nbsp;^uuiui day.

16/11/26.
24/11/26.
1/12/26..
8/12/26..
11/12/26.
15/12/26.
22/12/26.
30/12/26.
7/1/27....
11/1/27...
21/1/27...
27/1/27...
3/2/27....
10/2/27...
17/2/27...
3/3/27...

35
29

41
31

34
72
38

51
25
29
40
17
38

76
50

36
04

43
41
47

45
56
41

46
59
43
85

3-2
3-4
3-5
2-7
2-0

2-3

3-2
3-2
3-2
3-3
3-2
3-6

3-7

4-1

3-9
41

4-3

3-9

4-8

3-9

4-7
4-0

411

(16/11) 200, (18/11) 200, (20/11)
300, (2/12) 2,000, (4/12) 2,000,
(7/12) 2,000, (9/12) 2,000, (11/12)
2,000 (14/12) 2,000, (17/12)
2,000 (19/12) 2,000, (21/12) 2,000
(23/12) 2,000 = 20,600 larvae.

In all tliese three cases it is not possible to state whether the
animals completely got rid of the infection or whether the infection
remained and they developed an immunity as a result of which they
were able to resist or completely to neutralize the effects of the
parasites.

In view of the .self cures reported by Stoll (1929), in the case of
two sheep, it is necessary to refer to a further recovery ca.se that was
encountered during the coure of this inve,stigation. this Slieep Xo.
11814, haeniatologi(?al records of which are presented in Table 11
and Graph 11, was at first used in a nodular worm experiment The
aiumal became at the same time accidentally, but naturally, infected
with wireworms. This was diagnosed by means of faeces cultures.
As a result of the wireworm infection, the animal developed a fairly
severe degree of anaemia, the red counts decreasing from a normal of
12-14 million to 5.5 million red cells per c.mm. of blood (l(i..\'i.2()).
After this the anaemia gradually improved. quot;When this was
observed, the animal was reinfected Avith large doses of //aenionr/nis
(■ontortns larvae, but completely resisted the infection, and when the
blood was finally examined, months later (27.11.26), the animal was,
from a haeniatological point of view, quite normal. In this work no
attempt was made to study the question of inimunitv in or resistance
to haemonchosis in sheep. This que.stion of acquired immunity with
metazoan and other })arasites in becoming increasingly important as
was shown by Taliaferro (1929) and other autliors quoted by li\'im
On referring to the differential counts (Table 11 and Graph quot;ll) it
will be observed that an undoubted eosinojihilia occurs, dui\'ing the
time the animal is recovering from the anaemia. It is notewortliy
that de Kock and Quinlan (192(5), also recorded an eosinophilia iii
splene(;tomized sheep at the time recovery from the anaemia due to
Anaplasmosis was taking place.

As previously stated, (luite a number of uninfected control slieep
were always kejjt separate from the infectted sheep, but oOierwise
under identical conditions of Iiousing, feeding and watering. These
control animals remained healthy and never developed any clinical
s.ymptoms. The haeniatological records of two of the.se sheei) are
given below.nbsp;^

Table 9 and Grajih 9 refer to Sheep Xo. 1J929. This is a youn««-
sheep free from worms. There is what is interpreted as a n\'ornuri
variation and fluctuation in the red counts, the haemoglobin and the
percentage vounie of red cells. In i,solated cases it will be oberved
that the haemoglobin and ])recipitate curves do not follow the red
count curve,s. This is probably due to errors in the red counts,
ihere is perhaps a slight downward trend of the curves in Graph 9.
Ihis is possibly due to the fact that in very young sheep the red cells
decrease in number as such sheep grow older.

Tnl)]e K) and (jraph 10 refer io^ Sheej) No. laOOl. Tliis is an
adult sheej) also free from worms. The led count, haemoglobin and
l)reci])itate curves also sliow a normal variation, but the fluctuations
are not so jionounced as in the case of the younger Sheep No. 11920,
and within the limits of nornntl vai\'iation the curves are practically
straight.

It is oI)vi(ms that the outstanding pathological effects of wire-
worms on sheep is the very severe and often fatal anaemia that is
produced, and it is of fundamental imjjortance to e.stablish definitely
the nuuiner in which this is brcmght about. It is remarkable that

these parasites, si)en(li]ig\' as they do their entire parasitic life in the
abomasum of sheep, can produce such profound cluuiges in the blood
of their hosts.

. Theoretically, anaemia can be due to : (1) The destruction and
disintegTation of the red cells by («) parasites such as occur iu the
piroplasnu)ses, or (h) toxic or other jirinciples which can conveniently
be classified as haemolytic substaiu\'es; (2) A disturbance or disease of
the blood-forming organs as a result of which the full ontogenitic
development of the red cells is interfered Avith and the nornuil rejilace-
ment of red cells cannot keep pace with those which are
b.eing daily eliminated in the process of normal wear and tear; (3) The
removal of tlie red cells due to phagocytic activity of certain cells in
the body. The anaemia is then due to excessive erythrophagocytosis.
Since the reticulo-endothelial system plays an active part in the
disintegration of red cells, e.g. in anaplasmosis in spleiiecf(uuised
sheep, according to de Kock (1923). erythrophagocytosis could per-
hajis more conveniently have been grouped and discussed under (J )
above; (4) The removal of red cells as occurs in haenionhage.

Hefoi\'e considei\'ing in detail into which of these groups the
anaemia of haemonchosis can iie placed form the known facts ol ihe
condition, and from the new evidence that is presented in this work,
an attempt will be made to review very briefly, and without pretend-
ing to quote exhaustively the tremendous literature that lias grown
around this subject, the A\'iews generally held as to the manner in
which parasites jiroduce their effects on the hosts. In general the
injurious effects ot jiarasites on their hosts can be groupe.l into one
or other of the foHowiiig: —

(/I) Nvfritirc DisiurhaiircK.—Either by depriving the host of
food, wliicli the gastro-intestinal parasites may assimilate, Iiefore
tins can become absorbed i)y the host, or by luoducing lesions in the
alimentary canal, as a lesult of which large iioiiions of the digestive
tract are rendered valueless for digestion and ab/sorption.

{/}) .]/rrli(iiilc(il inj)irgt;/ iiiflirfrd thniiu/ flic mijfralion of the
/xtrti.ilfc.s and Ixicfrrlal Infection tlirou(/li iroiinds mid Injuries.—Such
infection may have remote effects on various organs and tissues of the
body.

((\') To.rlc Suhsftnices.—\'l\'hi^vo. is the possibility that toxic sub-
stances, which are absorbed, may have a general or sjieciflc effect on
the body as a whole, or on particular systems, such as the circulation,
i-espiration, nervous system, endocrine organs, etc.

(I)) AiKienilti.—This may be due to (f) mechanical injury inflic-
ted on the mucous membrane and underlying tissues liy numerous
])arasites, particularly those equijiped with mouth parts such as
lancets designed for cutting, etc., and which secrete substances whicli
])revent the coagulation of the blood ; (2) the action of toxic prin-
ciples, (d) haemolytic sulistances secreted by the parasites, which
when absorbed will iiroduce liaemolysis, possibly also the action of
haemolytic organisms which can gain entrance, through mechanical
injuries and wounds; (h) toxic substances which may cause injury to
tli\'e blood-forming organs.

Ill considering to what extent any of these conditions are involved
ill haenionchosis of sheep and in some other parasitic diseases, as
reported in the literature, they can he dealt with individually.

(A)nbsp;No attempt was made to determine to what extent, if any,
nutritive disturbances are associated with the injurious effects of wire-
worms. It is not likely that this can be an important factor in
haenionchosis, as very often sheep which are heavily infe.sted with
wireworms are in fat condition, and it is doubtful if this depo.sition
of fat can be entirely ascribed as secondary to the anaemia.

(B)nbsp;The conditions enumerated under this heading may be
involved on rare occa.sions in so far as haenionchosis is concerned, and
will be referred to when s(mie iinii.sual lesions associiated with wire-
worm infection are described subsequently.

(C)nbsp;No such effects were observed or have been rejiorted in the
literature that was studied.

As previously stated, a systematic haematological study of the
anaemia due to wireworm infestation in sheep is not recorded in the
literature. On the question of toxic substances secreted by parasites,
a vast literature has, however, accumulated.

Schwartz (1921) very fully discusses what he calls hematoxins
from i)arasitic worms. He gives a (;omi)rehensive review of the
literature, and mentions 7-5 papers. The period covered hy this review-
is from 1865-1921. No attempt will be made to cover the same ground
in the literatuie, but some of the comdusions in the author\'s summary
of the recorded investigations on hemotoxins from iiarasitic worms,
will be referred to. He .states that: (1) certain parasitic worms
secrete harmful toxic substances, which are named heiyotoxins; fhe.se
hemotoxins are in general of a non-specific nature and may be active
on the blood of animals other than their normal hosts; (2) of the
cestodes, DiphyJJobnihrmm laivm, definitely contains haeniolytic sub-
stances; (3) Schistostomn jnponicum and worms belonging to the
genus Ascaris contain haemolysins; (4) hookworms, worms of tlie
genus Sfroilf/yJIIS and Gasfi-opliihis quot;larvae, secrete- haemolysins and
anticoagulins. Htieiiioiirhvs coiifortns is specifically mentioned as
apparently secreting a weak haemolysin and further wlii])wonns as
apparently secreting a haemolysin.

In concluding this summary, the author makes this statement:
quot; Owing to the fact that the direct abstraction of bl(M)d by parasites
appears to be inadequate as an explanation of the causes of anaemia
in parasitic di.seases, and in view of the fact that in tapeworm infec-
tions, which are accompanied by anaemia due entii\'ely to the pre.seiuie
of the parasites, the- .direct abstraction theory is inapplicable, the
view that haemolysins from parasites are of aetiological significance
in parasitic diseases appeared to he entiiely justified.quot;

In his own work on salt .solution extracts (if Hdemonchus con-
tortus on sheep and cattle erythrocytes, Schwartz (1921) conclude.s,
that the weakly positive haemolytic effects obtained do not favour
very strongly the view -which has been commonly ac(gt;epted as regards
the secretion of a haemolysin by this parasite.

Hookworm disease in man and some of the domesticated animals
has been extensively studied and, although Schwartz, just previously
quoted, concludes from his study of the literature that haemolysins
and anticoagulins are present in hookworms, Flue (1922) submits
evidence, in connection with hookworm disease of dogs, from which
he deduces : (1) the presence of anticoagulins in the cranial portions
of these hookworms; (2) the absence of liaemolytic substances; (3) that
the worms are able to produce not only chronic, but also profuse,
haemorrhage, which is sf)metinies fatal. He further concludes that
these facts favour the tlieory of chronic haemorrhage as the cause of
anaemia in hookworm disease of dogs.

Recently Chandler (1929) states that it is generally agreed that
hookworms do not cause anaemia ])y the secretion of a haemolysin.
Hookworms suck blood, and as a result of the action of anticoagulins,
the wounds keep bleeding foi\' some time after the worms have aban-
doned theni ; but the amount of bh)od in tlie faeces, even in severe
hookworm Infestation, is usually very small. He concludes: quot;It
seems fair to a.ssume, therefoi-e, that chronic loss of blood from the
intestine is at most a minlt;n- factor in hookworm disease, and certainly
cannot account for the severe anaemias so frequently seen in heavy
infestations.quot; He states further that quot; there seems to be little ground
for doubting that the anaemia is due primarily to a toxic effect on the
blood-forming organs.quot;

(^handler quotes de Lange as stating that hookworm anaemia is
primarily an aplastic one, caused by lo.ss of normal regenerative
power on the i)art of the blood-forming organs, due to toxins derived
directly or indirectly from the worms in the intestine.

^Ihaskar (1924) discusses the hookworm problem very fully, with
the exception of the ])athol()g^y and haeniotology of the condition. He
uses the Duncan Whytes riienolphthalein test to determine the
presence of occult blood, and finds that: (1) occult blood is absent in
cases free from hookworm infection; (2) it is present in 39 iier cent,
of infected cases; (3) it is present in 17.(S per cent, of cases for i)eri()ds
varying from 12 days to 4 months after the complete ex])nlsiou \')f
hookworms; (4) the intensity of the reaction has no correlation to the
number of hookworms harboured in the intestine.

All the cases examined were carefully selected aiul were free from
all causes known to lead to evacuation of blood with faeces. It was
sujiposed that the occult blood detected was due to haemorrhage con-
secjuent upon nlceration of tlie intestinal wall, brought about by liook-
•worms, but the author .states that he had no direct jiroof of this.

Scott (1930) believes that some of the acute anaemias in hook-
■\\vorm disease may be due to haemorrhage, but that the chronic,
anaemia does not s6em to be fully explained on the basis of blood

loss. Tlie remaining explanation, then, is a toxic depressing action
on the bonemarrow and other blood-forming organs, but he points oiit
that the pathology of these organs in chronic cases has not been
adeqiiately studied.

deferring now to the available literature in connection with the
anaemia of haemonchosis in sheep. Hall (1920) mentions tiiat the
stomach worms of sheep have the habit of attaching at one point for
a time and then moving away and attaching at another point, leaving
the old point of attachment bleeding for some time. This causes
anaemia, dry wool, oedematoiis swellings, and general unthriftiness.
The anaemia produced by stomach worms resembles that caused by
hookworms in man, dog, and sheep. The only way to differentiate
between the anaemia of hookworm and wireworm infections in sheep
is by post-mortem examination.

Donatien and Lestoquard state that anaemia of sheep and goats
may to-day be attributed to (1) worms, (2) blood parasites, (3) bac-
teria, (4) pernicious anaemia. Group (1) is discui^sed as parasitic
anaemia which can be caiised by Ui) distomiasis, (h) gastro-intestinal
strongylosis which is a jirogressive anaemia, with loss of appetite and
diarrhoea. The manner in which this anaemia develops is not dis-
cussed, neither is any evidence submitted in regard to changes jiro-
duced in the blood by uncomi)licated infection with the individual
strongyles; (c) trichocephalosis, and (c/) ovine bunostomiasis.

Hutyra and Marek (1926) state that the siroiigi/Udae bore into
the gastric mucosa and such blood from it. In this way they disturb
the nutrition of the host to a degree proportionate to their number.
More detrimental iirobably than the loss of blood is, however, the
absorjitioii of toxic metabolic products of the parasites.

The conclusion that one c(mies to in studying the literature on
hookworm disease is that in spite of the great quot;deal of work that has
been done, it is not definitely known what the pathogenesis of the
anaemia is. ft seems to be generally agreed that direct haemolysis
does not occ-ur. There are quite a quot;number of workers who believe
that the anaemia is due to haemorrhage from the intestinal tract, but
others maintain thaf, although this may be a somewhat insignificant
contributory factor, the anaemia is mainly caused by the action of
toxic products from the narasites themselves, or toxic bacterial pro-
ducts, or the combined action of these toxins on the blood-forming
organs, although it is difficult to reconcile a de])ressing effect caused
by toxins on the blood-fonning organs with the leucocytosis, which is
described by Sarless (1929) in some dogs experimentally infected per
ox with A/ih/Josfoina raiiiiiinii. Wintiobe (1931) suggests a (dassifi-
cation of the anaemias on the basis of differences in the size and
haemoglobin content of the red corj)uscles. The anaemias in his
Class 4 largely (\'omprise those resulting from chronic blood loss. The
characteristic; feature\'of these anaemias, according to this author, is
the decrease in the size of the red cells, accomi)anied by a relatively
greater decrease in the haemoglobin content. On this account he
suggests the term hypochromic anaemia. He found that the anaemia
in hookworm disease is of this type. With such an anaemia one
would expect to find a decrease in the colour, volume, and volume
colour indices.

In the case of haeiuoncliosis in sheep, the anaeiuia-due-to-
haeniorrhag-e theory has its adherents. Other workers state that
haemorrhage, as well as toxins, causes the anaemia, but no evidence
is adduced as to how exactly the toxins are supposed to produce this
effect.

The four main causes of anaeniia previously referred to, will
now be iiidividuallv exainiiied, with the object of determininlt;gt;\' from
the available haematologicid and pathological facts that are already
known or have been established in this investigation, into wliich of
these grou])s the anaemia of haemonchosis can be classified.

If haemolytic toxins from wireworms or bacterial products be
al)sorbetl, the degree of haemolysis that is produced will depend on the
haemolytic potency of the toxin and on the amount of toxin absorbed.
When haemolysis occurs the haemoglobin will be dissolved in the
I)lasma and produce haemoglol)inaemia and, depending on various
factors, this may lead to haenioglobinuria and ])ossibly to luiemolvtit;
icterus. Irrespective of whether the haemolysis is of such a delt;quot;gt;ree
as to ])roduce haenioglobinuri a or icterus, derivatives of haemoo\'lobin
such as occurs in haeniosiderosis, must be found in the t issues,quot;quot;esi)e-
cially in those cases where the haematologicai examination reveals
a marked decrease over a short period of time in the number of the
red cells and in the absolute haemoglobin (iontent. There is no
evidence of an erythrorhexis or an erythrolysis such as is descrilied
by de Kock (1923) for enzootic icterus and anaplasmosis in spleuec-
tomize sheej) respet^tively.

How do the results obtained accord with these postulates?
f!liiucal i(;terus or haemoglobiiiuria never occurs in haemonchosis.
Haemoglobinaemia has never been observed. If haemolysis does
o(;cur, one would ex])ect, especially in those cases where the I\'ed cells
decrease to the extent of over 5 millions i)er c.mm. of blood, within
a week that haemoglobinaemia could be diagnosed by examining Die
plasma after ceiitrifuging the blood. This was always very careiully
done, and on no cx^casion was evidence of haemoglobinaemia observed.

In all the fatal exi)eriniental cases of haemonchosis, tlie liver,
lung, spleen, and kidney were sjjecifically stained for iron but none
could be demonstrated 111 these organs, with the exce])ti()ii of the
si)leen. A good deal of iron-containing pigment is normally ])resent
ill the s])leen, but in this organ, which in (piite a number of cases
was very much atrophied, it Avas even difficult to deinonsti\'ate the
jireseiice of any iron-containing jiigment at all. It can, therefore, be
definitely stated that no haemolysis occurs Avhich can ex])lain \'the
anaemia in haemonchosis in sheej). It is generally agreed that this
holds for hookworm disease also.

If this o(!curs. one must assume that the blood-forming organs
will reveal some moriihological evidence of such disturbance quot;and
sometimes, at any rate, a compensatory myeloid metaplasia in organs
like the spleen and the liver, as occurs in lymphomatosis, leucaemia,

and in carcinoma of the bonemarrow, according to Naegeli (1923),
and as occurs in lymphatic aleiicaemia in the dog, described by
i\'ourie and Ziehn (1930). It may, however, reasonably he argued
that the toxins are carried in the bloodstream and their effect ou the
spleen and the liver would also be such as to i)revent the development
of any myeloid metaplasia.

In all the fatal cases of haenionchosis, the bonenuirrow, including
the fat bonemarrow, was carefully examined histologically and the
only changes that were observed were those not of decreased activity
hut rather those suggestive of increased activity. Xumer(ms neutro-
phile and eosinophile myelocytes, as well as immature forms of
erythrocytes, were easily recognized in the sections. In the fat
honemarrow the fat spaces were extensively replaced by myeloid
tissue, ill which young forms of erythrocytes were freciuent and in
which the other usual marrow cells, such asmegakaryocytes, neutro-
phile and eosinophile myelocytes, etc., could be identified. The
neutrophilia, which o(;(;urs in nearly all cases towards the end of the
disease, is evidence of an actively functioning myeloid tissue. Should
the animal live long enough, with siudi a severe anaemia in chronic
cases one would exj)ect to find eventually exhaustion of the blood-
forming tissues, and the severe poikilocytosis and the quot; pessar-
formen quot; that occurs in some cases may be evidence that such ex-
haustion is taking place, although Naegeli (1923) points out that
j)oikilocytosis is of small diagnostic significance and is probably
dependent on (dianges in isotonicity of the blood. In the cases
studied, there was a fatal termination before well defined exhaustion
occurred.

That compensation was taking jilace is proved hy the myeloid
hyjierplasia of the fat honemarrow, contrary to what one would
expei^t where such a circulating toxin causing disturhaiu-es in the
blood-forming organs is postulated, such toxin should also teiid to
])revent the formation of any compensatory myeloid hyperplasia in
the fat bonemarrow.

There is further definite evidence that, in a iiumher of these
fatal cases of haemoiudiosis, an in{;rease in the size of the cells
o(!c,urs and, a(;(;ording to Naegeli (1923), the presence of small cells
(mic\'ro(;ytes) is the most significant and distinctive feature of a hone-
mai\'iow insufficiency (Ivno(dienmarksinsuffizienz). Schilling (1922)
describes miciocytes as degenerative forms of erytliroc,ytes which in-
dicate degenerative (dianges in the bonemarrow.

It can, therefore, he concluded that, in the fatal cases of haenion-
chosis studied, there is no evidence of a disturbance in the blood-
forming organs interferes with the normal replacement of red
cells, which are daily being eliminated in the process of normal wear
and tear. There is certainly a disturbance in the blood-forming
organs, hut this is caused by and is settondary to the anaemia and
not the ])rimary cause of it.

The possibility that the lesions described in the liver and other
organs, can be caused hy toxic substances, will be discussed under
section (4) below.

Only on very rare occasions were cells, in which erythrophagocy-
tosis had occurred, encountered; this, as a cause of the anaemia, can
therefore be discarded.

The mouth parts and the buccal capside of wireworms are not
developed to the same extent as in hookworms, but nevertlieless tliese
parasites cut and lacerate the mucous membrane and such blood.
One hundred live wireworms were collected from a sheep that was
destroyed, were carefully washed in saline, then transferred to and
washed in distilled water, and finally transferred to a third receptacle,
also containing distilled water. In this they were ground up and,
after filtration the extract was examined spectroscopically, when
tyi)ical haenioglobin bands were identified. Hall, jireviously quoted,
states that when (he i)arasite detaches, as it has a habit of doing, it
leaves the old point of attachment l)leeding for some time, aud
when hundreds of worms are pre.sent in heavily infested individuals,
it is not inconceivable that sei\'ious effe(\'ts will be produced.

In ty])ical and fatal cases of haemonchosis, the abonui.sal contents
are of a brownish clux^olate colour, and are strongly positive for
haemoglobin, when tested with tincture of guaiaconic acid. Positive
tests with this reagent may even be obtained with the intestinal
contents. If one takes into consideration the large amount of food
and Avater that normally jiass through the abomasum a gieat deal
of blood mu.st continuously flow into the abomasum, in order to
I)i()(luce this discolouration of the abonuisal and eveji the intestinal
contents.

f 11 most cases the anaemia begins to develop from the third to the
sixth week after artificial infection. If it is considered that it takes
three weeks for the parasites to become adult and allowance is made
for an initial stimulating eifect resulting in an increase in the number
of red cells, it seems doubtful that toxins could produce the anaemia
in such a short jieriod of time. Owing to the relatively few cases
in which a ])rogressive anaemia deyeh)ped, no attenqit was made to
destroy the ])arasites in an animal in the later stages of the disease,
in order systematically to trace the regenerative changes in the bhxxl
during recovery, but from practical experience it (!an be stated that
infested animals nearly always recover and rajiidly imjjrove after
ai)l)roi)riate medicnnal treatment. It seems unlikely that a bone-
marrow, which has been so severely damaged by toxins that it cannot
maintain even two million cells i)er c.mm. ot blood, should imme-
diately the toxins are removed be capable of producing sufficient
cells to meet the ordinary relt;iuirenients of the body.

It is now necessary to consider whether or not (1) the morpho-
logical c.hanges in the i-ed cells, (2) the changes in the various indices
retîorded, and (-\'5) the pathological lesions described support the con-
tention, that the anaemia is due to haemorrhage along the alimentary
canal.

These are, briefly, i)oikilocytosis, polychromasia, punctate baso-
philia, and quot; pessarfornien.quot;

Poikilocytosis.—It seems to be generally agreed that tliis con-
dition is of no great diagnostic value, although Piney (1927) regards
it as a more definitely abnornud mode of regeneration that is aniso-
cytosis, as it never occiirs in normal individuals.

Polychromasia.—Naegeli (1923), Schilling (1922), Krumbhaar
(1928), and other authors recognize this as a sign of youth of the cell,
and as siich it must be associated with an actively functioning bone-
marrow. Piney (1927) states that polychromasia is simply a con-
dition of slight immaturity of the red corpuscles.

Punctate basophilia.—Naegeli and other authors maintain that
cells so atl\'ected are products of enibryological or pathological reactions
on the part of the bonemarrow, and are clinical nuuiifestatious of
pathological regenerative changes; but Krund)haar states that quot; it
is still doubtful if they are signs of youth or, as most authorities
believe, of degeneration.quot; Tlie same author quotes Lehmann, who
believes that basophile granules may be manifestations of either con-
dition.

As punctate basophilia is absent from the blood in aplastic
anaemia, Piney (1927) concludes that it is of regenerative significance,
but the fact that these cells showing this do not occur iu embryonic
blood indicates that they are the products of abnormal I\'egeneration.

quot; Pessarformen.quot;—These are large pale (;ells, which according
to Naegeli indicate degenerative forms or an insufficiency in the for-
mation of red cells in the bonemarrow. Sucli cells occur in the so-
called secondary anaemias, and in those stages of haemonchosis when
the limits of com])ensation have been reached. The presence of siu-h
cells may possibly be explained by the haemoglobin deficiency
developed on account of removal of blood along the alimentary canal.

In a number of cases there is a definite increase in the volume
index and in the colour index. The increase in these indices is due
to a uincrease in the size of the red cells. Some of these large cells
are fully haemoglobiniferous and can ajipropriately be classified as
nxegalocytes. Many of the nuicrocytes show polychromatic staining
and others contain punctate basophilic granules. These maci\'ocytes
must be regarded as yo\\ing cells and are the outj)ut of an actively
functioning bonemarrow, which is reaching the limits of compensa-
tion, and is no longer capable of turning out fully mature cells with
the result that young cells must be pushed into the circulation. That
the blood-forming organs are showing signs of exhaustion in the later
stages of the disease is confirmed by the decrease in the volume colour
index, and by th\'e presence of jiale cells, both of which iiulicate that
the cells are deficient in haemoglobin. These changes in the morpho-
logy of the red cells and in the various indices are exactly what one
would expect when internal liaenuu-rhage occurs. On referring to
Table 12 below, it will be seen that almost identical changes occurred
in the red cells of a sheep Avhich had been bled from the jugular
vein until a severe anaemia developed.

This sheep \\vas hied almost every day, up to GOO c.cm. of blood
being removed from the jugular vein at a time. Although large cells
such as megalocytes were easily recognized microscopically jirevious
to 13.11.29 macrocytes with polychronmsia and punctate basophilia
were for the first time numerous on this date, cells measuring up to
8.1/x being present. On IT.11.29, the blood was vitally stained and
numerous reticulocytes were recognized. Just before the animal was
destroyed on 18.11.29, the blood was again vitally stained, and the
reticulocytes were exceedingly numerous on this date. The coverslips
were removed from some of these vitally stained preparations, the
blood Avas spread on the slide and after quick drying Avas stained in

the usual Avay Avith Griemsa. In these permanent preparations, a
niicrophotograph of Avhich is reiiroduced (Fig. 14), no polychroinasia
is present, hut the reticuh)cytes are numerous. In the ordinary
smears, .stained by (jiemsa, there are numerous cells shoAving
polychronmsia, afnd it Avould .seem that the polychronmtic cells in
smears not vitally stained are the same as the reticuhicytes in the
vitally .stained quot;smears. This Avould tend to support those
haematologi-sts such as Ferrata (1909), Schilling (1922), and otiiers
quoted by Kruniphaar (1928), Avho helieA\'e that the quot; vitally stained
reticulum is an artificial clumping of the same substance that Avith
llomanoAvsky methods stains diffusely as polychroniatophilia.quot;

The colour index and the volume index in this case of external
bleeding is definitely increased. This is due, as in haemonchosis, to
an increase in the size of the red cells. The volume colour index
remains nornud, whereas in haemonchosis it is decreased. If the
animal could have been bled over a longer period of time, a deficiency
in haenioglobin, with a decrease in the volume colour index would
probably also have occurred.

It is noteworthy that the colour index, the volume index, and
the volume colour index in .some of these cases of liaeinonchosis are
exactly like those of pernicious anaemia in the human subject. There
is also a similarity in the morphological changes that occui\' in the
red cells, e.g. anisocytosis, poikilocytosis, polychromasia and ])unctate
basophilia, although undoubted inegaloblasts, as such, were never
identified in ca.ses of haemonchosis. In pernicious anaemia there is a
leucopenia and a relative lympliocyto.sis and Tiney (192T) regards
this as evidence of defective myeloid function. There is, on the con-
trary, a tendency towards a leucocytosis in haemonchosis, which would
tend to support the view that in haemonchosis the bonemarrow is not
defective.

Except for the myeloid hyperplasia in the fat bonemarrow and
other evidence of active erythroi)oiesis, the lesions in peniicious
anaemia of the human subject are entirely di.ssimilar to those of
haemonchosis in sheep. The erythrophagocytosis, myeloid metaplasia,
and liaemosiderosis, which occur in jiernicious anaemia, find no
(•(ninteri)art in the lesions of haemonchosis. Erom this it can be con-
cluded that the injury to or the disturbaiu-e in the red cells must be
different in the two conditions.

The lesions that ai\'e most consistently encounteied in
haemonchosis of sheep are (f) lesions resend)liiig necrosis around the
central veins of the liver, and (2) the ])resence in the cells around the
central veins of substances which stain with Sudan III and with Xile
lUue Sulphate, but which are .soluble in ah\'ohol; and further the
presence in sonu^ of (he cells, not only of the liver, but also of most
of the organs of the body, of peculiar crystals, Avhich resendile those
Avhich occur in fat necrosis. The presem-e of these substances which
are not true fats but probably related substances, may be associated
Avith changes in fat metabolism in the liver and elseAvheie. All these
lesions are probably dejiendent on circulatory and nutritional
disturbances, due to the anaemia. The peculiar distribution of the
lesions just around the central veins of the liver suggest this, (jwing
to the anaemia, the total amount of oxygen is deficient. In the case
of the li\\\'er, those ])arts fii\'st reached by the blood Avill readily absorb
nuich of the aA\'ailable already depleted oxygen, and by the time the
l)lood has tloAved to the region of the central A-eins, sufficient oxygen
is no longer available, and these j)eculiar lesions of characteristic dis-
tribution develop. MacCallum (f922) mentions a number of condi-
tions of the li\\\'er, e.g., chronic pas.siye congesticm, chloroform
poisoning, etc., Avhere the lesions are confined to the cells around the
cential veins, and he makes the statement that quot; one cannot doubt
the determining influence of the bloodstream in ])roducing these

ditferences distribution, altliough it is not always easy to under-
stand it.quot; This author believes that, in chronic venous cong-estion,
tlie peculiar distribution of the lesions around the central veins can
probably be explained on the basis of a circulatory disturbance, and
that those cells which receive the blood last are poorly nourished and
do not receive the proper supply of oxygen. It is\' nevertheless of
importance to consider whether such lesions can be produced by toxic
substances circulating in the bloodstream. In this connection one
would expect that those portions of the liver, namely at the periphery
of the lobules, which are first reached by the blood, should show, in
a greater measure, the effects of the injury; but (^pie, quoted\' by

MacCallum (1922), maintains that in intense infections, and especially
where a toxic injury is combined with bacterial infection, necrosis may
occur in a part of the lobule midway between its periphery and the
central vein. It seems, therefore, that on the basis of the distribu-
tion of the lesions ^done, the possibility of toxic action cannot be
absolutely excluded.

^ The cry.stals described are mtwit specific for wireworm infestation.
They are present in the cells of the livers from .sheep which had been
splenectomized by De Kock and (juilan (192(;), and which sub-
se(iuently developed anaemia due to anaplasmosis. They are also

present in the liver cells of sheep that were bled until a severe degree
led. The section shown in Fig. 15 is from such a

case. Tlieir presence seems to be consistently associated with anaemia
of the sheep, although they were also recognized in the liver of some
cases of heartwater, but were absent in other cases of this disease.
It is, however, not by any means certain that all the shee]) which
died from heartwater were entirely free from parasitic infestation.
The crystals were demonstrable in organs which were cut and examined
within a few days after formalin fixation and also when these organs
after jireliminary fixation in formalin had been kept for months in
Ivaiserling. That they are not artefacts produced in the Kaiserling
is further ju\'oved by their absence from the cells of many other organs
that were so pi\'eserved.

It can, therefore, be concluded that : (I) the wireworms ingest
blood and pierce and cut the mucous membrane and underlying tissues
of the ahomasum, as a result of which there is constant haemorrhage
into the ahomasum. This causes discolouration of tlie abomasal and
intestinal contents.

(2)nbsp;Thei\'e is a rapid iiroduction of the anaemia in severe cases of
wireworm iiife.station, with jirompt and complete recovery when the
jiarasites have been destroyed.

(3)nbsp;The anisocytosis, the ptdychromasia, the Jolly bodies and
jirobahly also the punctate basophilia, the active erythropoiesis with
myeloid liyperjilasia, the plus colour index, and the jilus volume index
indicate active regenerative changes and must be associated with an
actively func.tioning bonemarrow.

(4)nbsp;The ])oikilocytosis, the jiale cells (iies.sarformen), and the
decrease in the volunie «•olour index indicate commencing exhaustion
of the blood-forming tissues.

(b) The lesions in the liver and elsewhere are ])rohably due to
circulatory and nutritional disturbances and changes in fat
nietaholislu, dependent on the anaemia, hut the iiossihility that toxins
may ])roduce such lesions cannot he entirely excluded.

((i) With the exce])tion of the lesions, like those of necrosis,
occuri\'iiig around the central veins and the decrease in the volume
colour index, identical luiematological and pathological^ changes are
])resent in acute cases of //(iciiiotirlius roiilortiix infestation in .shee]),
as also in sheej) bled daily from the jugular vein until a severe degree
of anaemia has been jiroduced.

fn view, therefore, of the facts that : {a) there is no haemolysis,
(h) there is no evidence of a jiriniary disturbance in the hlood-foi\'in-
ing organs, which interferes with tlu! normal rejilacement of red cells
da7ly eliminated in the jiroce.ss of nornial wear and tear, (r) there is
very little, if any, erythroiihagocytosis, and (d) there is ])ositive
evidence that the\'worms ingest blood ami undoubtedly cause con-
siderable haemorrhage into the ahomasum, it is justifiable to conclude
that the anaemia is due (1) to the haemorrhages which occur at the
jioints where the worms attach and detach, and (2) to probably a
much smaller extent to the ingestion of blood by the parasites.

When numerous parasites are present,^ a marked anaemia can be
lu\'oduced in a relatively slun-t period of time. The initial effect of
this removal of blood is to .stimulate the blood-forming organs to

increased activity, resulting in a temporary polycythaemia or
•erytlirocytosis. Very soon, liowever, a progressive decrease in tlie
number of red cells takes i)lace and when the bonemarrow can no
longer meet these enormous demands for red cells, a compensatory
myeloid hyperplasia, which also involves the fatty bonemarrow,
takes place. Eventually a state of affairs is reached when the blood-
forming organs cannot supply sufficient adult cells for the circulation,
and 5^oung immature forms are released into the circulation. This
explains the anisocytosis, the polychromasia, the Jolly bodies, the
plus volume index, the plus colour index, and probably aL-:o the
punctate basophilia. During the further course of the disease, how-
ever, the bonemarrow gradually becomes exhausted, degenerative
forms, such as poikilocytes and jiale cells, make their appearance, and
with the enormous elimination of haemoglobin along the alimentary
canal, there is eventually also a haemoglobin dificiency in the cells,
as IS indicated by the decrease in the volunie colourquot; index. As a
result of the anaemia there is probably a disturbance in the fat
metabolism of the body. This leads to th^e appearance of related fatty
substances and crystals in the cells of various organs, but particularly
of the hver. Further, lesions like those of necrosis, dependent
probably on circulatory and nutritional disturbances due to tiie
anaemia, develop around the central veins of the liver.

That somewhat similar lesions and practically identical haema-
tologicai changes occur when sheep are bled from the jugular vein
until a severe degree of anaemia develops is very strong confirmatory
evidence that the changes in the bh)od picture of haemoncliosis i\'n
shee]) are not due to a primary disturbance in the bonemanow, but
are the result of, and secondary to, the anaemia.

On three occasions infarcts were found to be present in the hearts
of sheep that had a severe wireworm iiife.station. In the one case an
embolus or thrombus was located in the left coronary artery, in whicii
it formed a nodule that could easily be felt with the finger. On the
ves.sel being opened and embolus oquot;r thrombus removed, two smaller
branches of the left coronary artery were found to be completely
occluded at this point, and that portion of the myocard supplied b^
these two branches was of a dark red colour. The area involved i\'n
the infarction measured 5 by 2 cm. Fig. Hi. No emboli or thrombi
could be detected in the lungs. The valves and endocardium of l)otii
the left and right portions of the heart were in no way diseased. In
this ca.se the origin of the emboli could therefore not be traced.
Even theoretically it is difftcult to coiu^eive in what way the wirewoini
infestation, or even the anaemia produced by it. could cause the
formation of emboli or thrombi in the coronary arteries.

In this same animal there were numerous ulcers in the abomasum.
In many cases, as will he seen from the accompanying photograph
(I\'lg. 17), numerous wireworms are attached to these quot;ulcers. In some
cases the ulcers are elliptical mid measure as much as 3 by 2 cm., in
other cases they are very irregular in outline. The depth to which
the ulcers extend into the wall of the st(miach, varies very much :

some are superficial while others penetrate deeper into the suhmucosa,
and in the more severe cases they may even extend through the mus-
cular laj^ers and are then apparently only limited hy the serosa.

1 am not aware that the view has ever heen advanced that Avire-
Avornis can he responsible for ulcers in the ahomasum. It seems
probable that the injury inflicted on the mucous mendn\'ane by these
parasites may, in some cases, upset its nornud protective mechanism,
and there may then deA\'elop peptic dige.stion of the stonmch Avail; or
certain bacteria nuvy he responsible for the destruction of the issues
in a secondary manner. That the Avorms themseh-es destroy the
ti.s.sues and cau.se the ulcers, is most unlikely. It is more difficult to
understaml the pathogenesis of the infarction of the heart. No
thrombi could he detected in the lungs, nor Avere the A\'ah\'es and
endocardium in any Avay diseased. It is possible that bacteria gained
entrance to the circulation through the idcers in the abonmsum, and
Avere able to produce injury to the intinui of the coronary artery,
Avith thrond)us formation in a heart Avho.se resistance Avas decreased as
a result of the anaemia, fn anaemia the heait is undoubtedly called
upon to do a great deal of extra Avork, as the smaller number of red
cells must circulate so much more frequently in order to supply the
necessary amount of oxygen. This Avould oc^cur in spite of the
l)resence of certain comjiensatory factors, ft is, for exam])le, Avell
knoAvn that sheep Avith severe anaemia from AvireAvorm infestation are
easily fatigued; and the jirobalitiy is that these animals are less
actiA-e than nonnal, and conseiiuently do iu)t require the same amount
of oxygen as do normal animals.

(1)nbsp;Sheep blood takes longei- to pi\'ecipitate than horse blood.
When centrifuging normal citrated sheep blood in an electric centri-
fuge running at 1,500 revolutions per minute, one obtains constant
realt;lings in 00-70 minutes time. Under similar conditions, the hhiod
of sheep Avith severe anaemia Avill give constant readings in 20-30
minutes.

(2)nbsp;Uniform lelative results aie obtained Avhen haemogiohin
determinations on sheep blood are made in a Duhosci colorimeter,
using a NeAvcomer disc as standard.

(3)nbsp;In order that I\'eliable colour, volume, and volume colour
indices nuiy he calculated, it is advocated that normality for each
individual shoidd first of all he established during the i)re-infection
period.

(4)nbsp;Of 38 Avorm-free sheep that Avere artifiïdally infected Avifh pure
faeces cultiires of /faenionr/nis coiiforltis larvae, 9 deA\'eloped a fatal
progre.ssiA-e anaemia, and 0 developed anaemia from which they
recovered Avithout any medicinal treatment (so-called quot; recovery
cases quot;). One furthei\' recovery (-ase resisted repeated attempts at
infestation Avith large doses of AvireAvorm larvae. The remaining 23
sheep either resisted infection or did not iihoAv any effects of infesta-
tion

(5) In llaenionchosis tliere is {a) no icterus, haemoglobinaemia or
haenioglobinuria, because haemolysis does not occur; (6) no evidence
of a primary disturbance in the blood-forming organs, interfering
with the normal replacement of red cells which daily are being
eliminated in the process of normal wear and tear, xiny disturbance
that is present in the bonemarrow is secondary to the anaeniia ; and
(c) very little, if any, erythrophagocytosis.

(G) The wire\\yorms ingest blood and cause haemorrhage into the
abomasum, resulting in a chocolate discolouration of the abomasal
(•(mteiits. This haemorrhage and the ingestion of blood by the
parasites is the cause of the anaeniia, which shows the following
characteristics : (a) there is probably an initial jjolycythaemia or more
particularly an erythrocj^tosis due to the stimulating effect produced
by the haemorrhage, etc. {li) degenerative forms of erythro(;ytes are
present, e.g., cells showing anisocytosis, polychromasia and -Tolly
l)odies. Punctate basophilia is also present and can probably also be
included with regenerative forms. When such regenerative forms
and megalocytes predominate, there is an increase in the colour index
and the volume index, due mainly to the increase in the size of the
red cells. (r) Degenerative forms are present, e.g.. pale cells
(pessafornien), poikilocytes, and possibly punctate basophilic cells.
These indicate commencing- exhaustion of the blood-forming organs
and associated with them is a decrease in the volume coh)ur (satura-
tion) index, i)ointing to a relative deficiency in haemoglobin.

(7)nbsp;Xo lesions which can be regarded as si)ecific for haemonchosis
are iiresent. A myeloid hyperplasia is i)resent which also involves
the fat bonemarrow, and is secondary to the anaeniia. Lesions like
those of necrosis immediately around the central veins and the
presence of related fatty substances and crystals in the cells of the
liver, as well as in cells of other organs, are i)robably due to
circulatory and nutritional disturbances, and to disturbances in the
fat metabolism of the body as a result of tlie anaemia.

(8)nbsp;With the exception of the lesions, like those of necrosis,
occurring around the central veins of the liver, and the decrease in
the volume colour index, identical haematologicai and ])athological
changes are present in acute cases of Jlaemonclms contorUis infesta-
tion in sheep and in sheej) bled daily from the jugular vein, until a
severe degree of anaemia has been produced.

(10)nbsp;The colour index, the volume index, and the volume colour
index of haemonchosis are exactly like those of many cases of
pernicious anaemia in the human .subject. The morphological changes
of the red cells are very similar to those of the latter disease except
that, in the fatal cases of haemonchosis studied, no megaloblasts were
identified. The lesions, however, are entirely dissimilar, and
haeniosiderosis, erythrophagocytosis, and the myeloid metaplasia of
pernicious anaemia are not present in haemonchosis. From this it is
evident that the nature of the injury in or the disturbance to the red
cells must be different in the two conditions.

(11) Some iinusual lesions, e.g., infarcts in the heart and ulcera-
tion of the ahomasum, were on rare occasions found in fatal cases of
haenioiichosis.

This work was first of all suggested to me by Sir Arnold Theiler,
the late Director of Veterinary Education and liesearch, Onderste-
poort, I\'nion Department of Agriculture.

I wish to record my thaidcs to niy colleagues the late Dr. C. P.
Neser and Dr. (t. de Kock for valuable advice, and to Mr. 1\'. C. van
Niekerk, Senioi\' Lay Assistant, for assistance in the haematological
work.

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De toediening aan vee van oplosbare phosphaten in het drink-
water, in phosphor-arme streken van Zuid-Afrika, heeft velevoor-
deelen boven andere methoden van toediening van deze stoffen.

Page 12, 3rd last paragraph. 3rd last line read of for on.
Page 15, 2nd paragraph, 3rd line read conjunctival and anal for con-
junctivat and anae.

Page 54, 2nd paragraph, 3rd line read course for coure; 8th last line
read is for in before becoming.

Page 61, 2rd paragraph, 5th hne read ontogenetic for ontogenitic.
Page 66, last paragraph. 3rd line, read interfering for interferes.
Page 72, last paragraph, 1st line read not for most.

Lji) ut L»ciiaiiuciiiiy VÖ11 pciicoc vdu ue vourmayen van net runu
is de toediening van ammoniumcarbonaat en nux vomica van bij-
zondere waarde.

De nieuwere physiologische gegevens omtrent de slokdarmsleuf
(Wester) kunnen dienen als uitgangspunt voor een rationeele be-
strijding van gastro-intestinale wormziekten bij de herkauwers.

De toediening aan vee van oplosbare phosphaten in het drink-
water, in phosphor-arme streken van Zuid-Afrika, heeft vele voor-
deden boven andere methoden van toediening van deze stoffen.

De aanwezigheid van morphologisch niet van Koch\'sche lichaampjes
te onderscheiden vormsels is niet altijd een zekere aanwijzing voor
Oostkust-koorts.

Een sporenhoudende miltvuurentstof is in het algemeen meer
betrouwbaar en doeltreffend, dan miltvuurentstoffen, die bestaan
uit de bacillen.

In sommige gevallen van aleucaemische lymphatische leucose van
honden treedt niettegenstaande een uitgebreide vernietiging van
beenmerg, slechts een geringe anaemie op. Dit is het gevolg van
een myeloïde metaplasie in de milt, met overwegende vorming van
erythrocyten.

Bij de behandeling van parese van de voormagen van het rund
is de toediening van ammoniumcarbonaat en nux vomica van bij-
zondere waarde.

De nieuwere physiologische gegevens omtrent de slokdarmsleuf
(Wesfer) kunnen dienen als uitgangspunt voor een rationeele be-
strijding van gastro-intestinale wormziekten bij de herkauwers.

De functioneele toestand van het maagdarmkanaal is van princi-
pieele beteekenis voor de werking van therapeutische clysmata bij
de oesophagostomiasis van schapen.

De optimale doseering van een sporenhoudende miltvuurentstof
kan beter bepaald worden langs biologischen, dan langs morpho-
logischen weg (tellen der sporen).

De normale ontwikkeling van Oesophagostomum columbianum
bij het schaap verloopt in de darmwand vrijwel zonder reactie.

ppt.	after 10	minutes	10	45
) J	„ 20	jgt;	9.5	.38 \'35
J gt;	„	gt;)	9
; ,	„ 40	))	9	34
J J	„ oO	f)	9	32
J )	„ ()()	rgt;	9	31
gt; gt;	„ 70	y)	9
})	,, 80	))	9	30
» t	„ 90	) gt;	9	.30
J \'	„ 100	)gt;	9	30

Date.	Source.	K.C.	K.P.	Hglb. %	.Serum.	W.C.	L.	M.	X.	E.	B.	V.C.I.	C.l.	VM.	Remarks.
3/11,25	Jugular	I:J-5	36	86	Clear	4,600	63	5	31	1	0	I-00	0-98	0-99	Red cells, normal.
5/11/25	12-3	34	84	1	7,200	70	0	20	I	0	1 03	I • 06	1-03	Red cells, normal.
0/11/25	,,	11-7	30	72	99	1 6,000	61	3	34	2	0	1-00	0-9lt;i	0«95	Red cells, normal.
11 11/25	9gt;	13-4	33	78		6,100	65	0	34	1	0	o-oo	0-91	0-91	Red cells, normal.
20 11/25	9 9	13-0	36	83	1	! 6,500	66	1	32	1	0	0-96	0-93	0-96	Red cells, norma.
25/11/25	99	10-3	34	78	1	0,800	54	I	42	2	1	0-96	M8	1-22	Red cells, normal.
2/12/25	99	120	33	81	»»	6,400	57	o	30	I	1	103	1-05	1-02	Bed cells, normal
10/12/25	99	11-7	33	80	J»	8,200	.55	0	45	0	0	1-05	MO	1-04	Red cells, normal.
17/12/25	99	11-4	33	81		,5,100	60	0	30	1	0	I-03	Ml	1-04	Red cells, normal.
2.-J \'12/25	99	10-5	35	81		7,COO	56	2	40	2	0	0-97	1-20	1-23	Red cells, normal.
20/12\'25	99	0-6	26	70	i	4.8Wt	H4	2	31	3	0	113	113	1-00	Red cells, normal.
7 1/26	99	4-4	15	34		((,roo	58	0	42	0	0	»■95	1-20	1 • 26	Anysocytosis. Suggestion of
		i			1			1						polychromasia occ. .Jolly bodies.
0/1,26		3-3	10 1	23		8,4IK) 1	26	o	72	0	0	0-0(i	1 -08	M2	Anysocytosis. Suggestion of polychromasia occ. Jolly bodies.

Date.	Source.	R.C.	R.P.	Hglb. %	Vis- cosity.	W.C.	L.	M.		E.	B.	V.C.I.	C.I.	V.I.	Remarks.
3/11/25	Jugular	11-8	35	90	_	7,800	()9	5	26	0	0	Ml	1-01
5 /] 1 /25	»J	»•6	35	78	—	10,500	84	0	14	1	1	0-96	0-92
10 /11 /25	tgt;	10-2	33	78	—.	12,700	67	3	30	0	0	1-02	0-98
12/11/25	jgt;	10-3	31	72	—	10,300	(i5	4	30	1	0	1-01	1-08	_
20 / 11 /2a	„	11-6	39	84	—	9,000	63	1	.36	0	0	0-93	0-96	_
26/II /25	J)	12-1	40	87	—	7,800	89	5	(gt;	0	0	0-90	0-95	_
3/12/25	»»	10-5	34	83	—	9,100	88	3	9	0	0	I 05	1-04	_
11/12/25	„	12-8	40	92	—	8,900	75	3	21	0	1	0-99	0-96	_	Cells normal.
18/12/25	„	10-8	35	87	—	9,100	84	2	■i2	1	1	1-08	1-07	_	Cells normal.
24/12/25	„	13-0	40	93	—	9,300	53	6	40	1	0	1-01	0-95	_	Cells norma.
30/12/25		11-7	35	81	3-5	7,000	(»9	4	24	3	0	1-00	0-92	_	Cells normal.
8/1/2G		12-4	40	89	3-6	8,300	76	1	23	0	0	0-91	0-95	_	Cells normal.
11/1/2G		9-9	29	67	3-9	3,900	72	1	27	0	0	I-00	0-90	_	Cells normal.
13/1/26		10-3	29	70	3-0	4,500	66	3	.30	0	1	1-05	0-90	_	Cells normal.
21 /I /26	»	5-5	16	48	2-3	8,4(M)	76	4	18	I	1	1-29	1 ■ 16	—	Anisocytosis well marked. Anisocytosis well marked.
23/1 /2G		5-6	16	47	.gt;..)	6,900	87	2	11	0	0	1-27	MI	—
27 /] /26		4-5	12	.35	2-0	6,300	76	0	23	1	0	1-26	1-03	—	Anisocytosis and poikilocy-
29 /I /26															tosis.
	4-6	14	3(i	2-0	8,200	72	I	26	0	1	1-11	1-04	—	Anisocytosis and poikilocy-
3/2/2G														*	tosis.
	4-8	11	.33	1-6	5,0(K)	69	1	30	0	0	1-29	0-91	—	Anisocytosis and poikilocy-
		5-0	12												tosis, occasional Jolly bodies.
5 /2 /26	lgt;	3.3	1-6	(i,000	59	0	41	0	(1	M9	()-87	—	Anisocytosis and poikilocy-
8/2/2G															tosis.
gt;gt;	6-fi	17	48	1-9	•\',000	32	.3	65	n	()	1 05	0-82	—	Anisocytosis and poikiloc}\'-
10/2/26			20												tosis.
	G\'5	42	1-9	7,«M)0	25	1 i	74	0	0	0-91	0-8(i	—	Anisocytosis and ])oikilocy- tosis.

Date.	Source.	R.C.	R.P.	Hplb. O/ /o	Serum.	w.c.	L.	M.	X.	E.	B.	V.C.I.	C.I.	V.I.	Rem,arks.
29 /4 /29	Jugular	11-3	36	84	Clear	15,700	24	5	71	0	0	0-98	0-93	0-95	Cells normal in appearance. Cells normal in appearance. Cells normal in appearancc.
10/5/29	„	9-9	34	82	„	4,700	45	3	52	0	0	1-01	1-04	103
5/()/29	s,	9-4	32	79		5,100	56	3	41	0	0	1-03	1-05	1-02
10/6/29	?gt;	11-0	32	84		6,500	52	1	45	2	0	1-10	0-96	0-87	Occasional very large cells.
17/6/29		9-8	31	75		5,600	59	2	39	0	0	l-OI	0-96	1-00	Cells normal in appearance.. Cells normal in appearance. No evidence of anaemia.
21 /(5/29	J)	7-9	25	65		4,500	57	1	41	1	0	1-09	1-03	0-95
26/6/29	»»	5-6	19	48		5,500	54	1	41	3	1	1-06	Ml	1-01
1 !- /29	quot;	4-0	15	36		5,200	59	0	40	0	1	1-00	M3	M2	Anisocytosis. Slight polychro- niasia and occasional punc-
			15				54								tate basophilia.
0 /7 /29		2-8	25		5,200	2	43	I	0	0-69	1-12	1-60	Anisocytosis; polychromasia and punctate basophilia very marked.
8/7/29		2-6	19	24		8,800	44	4	50	1	1	0-53	1-16	214	Anisocytosis, polychromasia and punctate basophilia very marked, DIED, 10/7/29.

Date.	Source.	R.C.	R.P.	Hglb. 0/ /o	Vi.ico- sity.	W.C.	L.		N.	E.	B.
6/1/26	.Tugulai	8-6	31	79	3-0	8,100	81	2	10	1	0
7 1 \'26	8-6	29	81	3-2	7,400	70	2	26	2	0
8/1,\'26		!)-3	33	78	3-0	0,400	73	5	18	2	2
11,1 26		!)-0	34	81	—	6,400	72	1	26	1	0
12/1/26		9-3	32	81	3-2	6,500	(i3	5	28	3	1
13/1/26		9-3	35	89	3-2	7,700	76	3	21	0	0
14/1 /26		8-2	30	79	2-9	6,700	71	1	26	1	1
18/1/26		7-6	30	79	3-3	7,(R)0	unabl	e to CO	unt
10/1 \'20		9-2	37	84	3-3	7,300	63	1	31	4	1
20 11 26		lO-O	39	81	30	6,000	unabl	0 to CO	unt	_
21 11/26		9-3	.34	84	3-0	8,600	69	2	25	.3	1
22\'1/20		9-2	32	81	3-0	0,400	77	3	20	0	0
25 1 26		8-0	27	79	3-0	5,700	76	2	20	1	1
20 1/26		8-4	.,30	77	2-9	5,000	71	.3	23	2	1
27 1,\'20		9-1	30	80	3-0	8,900	()8	1	28	.3	0
28 1 20		lO-O	32	S4	3-0	6.800	67	5	24	4	0
2!) 1 20		10-0	30	87	3-0	7.100	72	4	22	0	2
1, 2 26		9-0	34	80	2-5	5,300	(i7	.)	27	3	1
2/2/20		9-0	32	77	2- 2	4.900	77	0	21	2	0
2/2/2t)		lO-O	37	93	2-5	(),20()	74	.3	21	1	1
4 . 2/26		9-0	32	84	2-4	0,400	70	1	23	6	0
5/2/20		8-5	33	78	2-3	8,500	74	1	22	3	0
8\'2/20 !)/2/26		9-0	32	80	2-4	10,300	55	0	.39	5	1
	9-0	32	80	2-1	10,600	()3	0	;!0	7	0
10/2/20		lO-O	37	9()	2-4	7,300	unabl	e to CO	unt	—	_
12/2/20		10-2	34	90	2-5	5,900	50	0	34	8	2
15 2 26		10-2	.34	87	2-9	5,700	72	4	10	5	.3
10/2/26		8-4	29	76	2-9	0,000	62	2	32	3	1
17/2/26		9-4	3(i	81	2-9	7..3(MI	55	2	39	4	1
18/2 20 l!)/2 26		9-3	.30	84	3-0	8.700	78	0	14	5	.3
	9-9	.33	7!)	3-4	7,500	68	.)	24	4	2
22/2/26		10-7	.35	95	31	7.000	()8	2	25	2	3
23/2/2()		8-8	30	78	2-9	4..30()	()8	2	26	4	0
24/2/26		9-5	32	84	3-0	5,100	75	4	18	1	2
25/2/2Cgt;		10-9	33	84	3-0	7.100	77	0	21	1	1
2()/2/2()		91	.30	75	2-8	0,(i00	83	0	16	0	1
1\'3/26		10-9	.3(5	91	3-0	8..300	(gt;9	1	28	1	1
2/3/2(i		9-3	.30	80	2-9	5.500	09	5	24	2	0
.3/3/2(i		11-2	33	89	3-1	0,100	70		22	5	1
4/3/2()		no	35	90	3-1	8,500	(iO	.3	26	3	2
8/3/26		9-4	33	81	2-8	4,000	71	0	25	3	T
0/3/2() 10/3/20		I17	34	83	2-8	6.900	08	1	23	4	4
	9-4	30	78	3-0	6,000	02	2	,34	1	1

fter	H)	minutes 20	50
J gt;	20	»t	18	34
gt; 5	30	1»	u;	31
1 )	40	gt; ^	15.5	30
gt; i	50	*»	15	29.5
J »	GO	\' »*	15	29
gt; 1	70	, 9	15	2f)
1 y	80		15	29
			8


n
1	I
	\\
	V	V
	A gt;			s
			A \\
				i \\ \\

						\\\\
o«»						V

					•
								••o
^ IJgt; 5 Ml i_7 1 i 1 lt;»666777 29 Tlt;) 29 29 29 29 29 29 29 29
	1						A
						1	f	s.
						J
\\				/
	V




\\	V	/				fy
					\\ \'	\\
							.•V	lt;
						V

Dat«^.	Source.	R.C.	R.P.	Hdb. %	W.C.	L.	M.		E.	B.	V.C.I.	C.T.	V.T.	Remarks.
27 /11 ■/26	.Jugular	171	i50	120	9,000	54	1	40	3	2				No morphological obangc.s in red cells.
1 /12/2«		14-2	47	102	0,700	78	0	21	1	0	—	_	0-70	_
8/12/20		11-3	40	80	8,200	74	0	23	2	1	—	_	0-75	_
15/12/20		8.2	28	70	13,300	02	2	34	2	0	—	—	0-95	__
22/12/20	1»	0()	24	07	0,000	74	0	20	0	0	—	—	0-98	—
30/12/20		7-0	20	09	7,100	77	4	18	0	1	—	—	0-93	—
7/12/27		8-8	30	70	8,700	72	3	22	2	1	—	—	0-88	Serum pale yellow and cloudy. White layer on ppt.
11/1/27	J,	7 \'7	24	71	10,200	03	1	32	4	0	—	_	1-00	_
21 /] /27		8-5	29	84	7,000	7 i	0	14	7	2	—	—	1-00	_
27/1/27		9-8	35	93	9,800	Smear bad, unable to	count.		—	—	0-93	—
3/2/27		11-5	35	102	0,100	52	0	47	1	0	—	—.	1-00	_
10/2 /27		11-4	35	104	0,900	05	1	28	1	5	—	_	1-00	_
17/2 /27		10-4	31	9()	7,800-	08	1	2(5	4	2	—	_	1-08	__
24/2/27		11-0	37	lOS	4,700	lt;)8	0	30	1	1	—	_	1-02	_ .
3/3/27		12-4	39	111	(),()00	77	0	20	3	0	—	—	0-99	—

14-0	35	91
13-0	33	87
15-7	34	90
14-3	33	87
14-9*	39	90
15-9	43	108
17-2	44	114
15-7	39	107
16-9	41	104
17-4	42	107
16-3	39	100
11-0	34	81
12-0	34	79
11-5	33	73
9-3	25	61
91	20	56
9-3	23	60
12-8	26	75
10-7	25	07
12-4	33	79
131	34	80
13-5	38	87
14-4	39	92
16-3	41	101
13-4	36	90
13-8	36	■ 89
15-9	39	99
14-0	36	98
15-5	37	96
10-1	39	108
14-3	33	92
—	—	95
13-5	40	91
15-4	40	92
13-8	44	117

Date.	.Source.	R.C.	R.P.	Hglb. %	Vis- cosity.	W.C.	L.	jr.	N.	E.	B.
4/11/25	.Jugular	12-4	39	81	_	8,000	49	1	50	0	0
0/11/25	11-6	32	73	—	9,500	51	, 5	43	1	0
10/11/25		11-4	34	78	—	6,100	55	1	44	0	0
13/11/25		14-8	42	87	—	6,400	76	2	22	0	0
20/11/25		11-4	36	83	—	8,800	55	3	42	0	0
20/11/25		121	34	78	—	5,500	74	4	21	1	0
3/12/25		121	35	81	—	7,800	53	2	45	0	0
11/12/25 18/12/25		10-6	34	75	—	5,600	58	5	36	1	0
	IM	32	69	—	7,400	51	2	46	I	0
24/12/25		12-0	37	81	—	9,300	51	2	47	0	0
.30/12/25		13-6	43	91	3-5	6,800	68	.3	27	2	0
8/1/20		—	40	7»	3-2	7,100	61	0	.39	0	0
14/l/2()		10-0	30	72	31	4,800	()4	1	32	0	3
21/1/26		10-3	31	76	40	4.200	66	1 1	33	0	0
23/1/26		13-3	38	87	4-0	5,900	67	0	33	0	0
28/1/26		11-0	30	76	3-0	5..500	60	5	32	3	0
3/2/26		11-0	31	76	2-9	4.700	62	0	38	0	0
10/2/26		11-7	35	84	2-5	5,900	38	0	(iO	1	1
17, 2\' 26		12-0	3C)	87	3-3	6.100	53	0	47	0	0
23 2/26		ll-O	31	74	3-2	6,300	58	1	41	0	0
2/3/26 !»\';lt;/26		10-3	29	70	2-8	6,100	54	2	41	3	0
	111	32	75	—	4.300	.^O	0	50	0	0
l!)/3/26		11-3	29	72	3-1	5.100	62	1	34	2	1
26/3/26		(••8	25	62	2-6	4,700	72	3	24	0	1
30/3/26		11-7	32	77	3-0	3.400	55	.3	42	(1	0
!)/4/26		10-6	28	70	2-8	5,6(K)	47	1	52	0	0
16/4/26		!l-8	25	(i4	2-7	5,200	64	0	34	.gt;	0
30/4/26		11-8	33	81	3-1	4,500	68	3	29	0	0
5/5/26		12()	33	78	3-0	6,100	53	3	44	0	0
14/5/26		10-6	—	73	2-8	6.200	50	0	48	0	.gt;
21/5/26		!)-4	28	71	3-0	4,900	67	2	31	0	0
4/(!/26		JO. 2	.33	84	3-0	3,000	5lt;l	1	38	0	2

Date.	jSource	R.C.	R.P.	Hglb. o/ /o	Vis- cosity.	W.C.	L.		N.	E.	B.
3/11/25	Jugulai	13-8	39	90	_	13,300	58	2	35	4	1
5/11/25	14-5	39	99	—	10,000	55	.3	41	1	0
0/11/25		12-8	35	91	—	0,700	70	3	27	0	0
11/11/25		14-4	40	95	—	7.000	53	2	44	1	0
17/11/25		14-4	41	100	—	8.000	58	()	35	1	{)
23/11/25		13-!)	37	9«	—	10,100	03	5	31	1	0
30/11/25		14-2	40	100	—	10,700	54	3	38	3	2
14/12/25		13-4	37	95	—	10,300	52	1	38	9	0
28/12/25		13-8	—	90	—	12,200	40	.3	4!)	2	0
5/1/20		10-8	32	77	3-2	17,700	47	1	40	12	0
11/1/20		!)-2	27	09	3-0	9,700	48		37	8	5
18/1/20		lt;)-7	25	()5	3-0	8,100	,—	—	—	_	_
1/2/20		8-1	25	57	2-3	12,000	52	4	37	()	1
5/2/20		7-1	21	54	2- 2	9,400	49	3	42	2	4
8/2/20		7-4	24	57	2\' 2	11,000	(iO	o	28	d	4
1.5/2 20		7-0	—	58	2-8	11,800	58	.3	29	9	I
22/2/20		0-0	17	49	2-0	8.900	52	2	37	5	4
I, 3/20		7-0	24	57	2-0	11,200	44	2	45	()	3
8/3/2()		0-4	22	51	2-5	10,400	41	2	44	9	4
10/3/20		_	2.3	52	2-7	11.800	43	()	43	0	0
22/3/20		7-3	2.3	52	21	7,100	3(i	5	45	10	4
2!)/.3/2(i 8/4/20		7-«	23	55	2-0	12,900	37	3	54	4	• gt;
	7-3	■gt;2	53	2-0	9,900	51	5	37	4	.3
12/4/20		7-0	2.3	50	2-7	10,700	40	5	38	11	0
20 \'4/20		0-5	20	53	3-1	12,000	47	3	42	7	1
3/5/\'20		_	25	58	31	12,9(KI	45	0	40	10	5
10/5/20	»»	8-8	28	(i.3	3-4	11,700	49	1	42	7	1
I7/.5/2()	!)■!)	32	75	3-0	15,200	.35	2	()()	3	0
2()/.5/2()		0-!)	23	()()	3-0	9,700	40	2	35	14	3
0/0/20		8-0	20	()5	3-4	12,800	47	4	31	10	2
23/()/20		8-7	25	()3	—	11,000	.50	1	33	11	.5
2!)/()/2()		8-5	27	(iO	3-5	11,000	54	:$	34	7	2
20/7/2(i		100	33	74	3-9	10,800	47	4	33	14	2
27,11/20		12-2	37	9()		13,700	47	5	39	9	0



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