B. M.
PRASAD
55
method recommended by Piney [1931] was generally followed. Immediately after air-
drying films were put in a glass-stoppered jar containing two per cent osmic acid and
allowed to stand for 30 seconds for complete fixation. They were then washed thoroughly
with distilled water and stained for 10 minutes with a mixture of equal parts of a 1 per
cent solution of alphanaphthol and para-phenylenediamical. They were then washed in dis-
tilled water and mounted without drying on water glass, oxidase granules being stained
blue. The absence of peroxidase granules together with sharper outlining of the nucleus
differentiated the pathological lymphocytes from myeloblasts. The results obtained by the
two methods were found to agree. Haemoglobin was estimated by the Sahli method.
OBSERVATIONS
During the sub-clinical period following the infective inoculation, there was a slight
leucocytosis, all the cells taking part in the increase but with a slight tendency towards
lymphocytosis. On an average, an increase of about 8 per cent was recorded.
From the onset of clinical symptoms, characterized by a sudden rise of temperature
usually 13 or 14 days after giving the infected blood, leucocytes decreased, ultimately reach¬
ing a marked leucopenia persisting for two or three days during the post-clinical period
or until recovery was under way. The average total white-cell count worked out at about
16,000 per c. mm. of blood; a drop to 3,400 and in one case to 1,840 is worthy of notice.
But, although the number of leucocytes was appreciably reduced, there was a marked
monocytosis at the expense of other cells. The mean percentage of the various types of cells,
as shown by the differential counts made on the animals used in the investigation, was as
follows : lymphocytes 54 per cent, neutrophiles 28 per cent, eosinophiles 6 per cent and mono¬
nuclears about 8 per cent. One bull showed a high percentage of eosinophiles which may
have been due to helminthic infection. The average percentages, as shown during the period
of full clinical manifestations, were as follows : lymphocytes 6 per cent, neutrophiles 2 per
cent, mononuclears 91.5 per cent and eosinophiles 0.5 per cent. These figures show a
marked increase in monocytes and a relative decrease of lymphocytes, neutrophiles and
eosinophiles. Of the monocytes, a certain percentage appeared to be myeloblasts.
Karyorrhexis in the white corpuscles belonging to the hyaline series, as observed by
Steck [1928] in the blood of animals with East Coast fever, was rarely encountered in the
peripheral circulation suggesting that the accumulated cells do not undergo rapid destruction
in the various organs.
There was also a slight decrease in the number of red blood corpuscles. From about
six to eight millions per c. mm. prior to infection, a decline to four millions and in one case
to three millions was observed. Thus a drop of 33 per cent to 50 per cent in red cells may
occur when the disease has sufficiently advanced. No variation, however, took place during
the sub-clinical period, hut the decrease became manifest from the onset of clinical symptoms
and, as in the case of the white corpuscles, persists until signs of recovery appear. It was also
apparent that there is no appreciable drop in blood haemoglobin during the disease.
Healthy animals in good condition appear to be more resistant to the disease than those
previously used for other work, e. g. on rinderpest This observation emerges from the
fact that of twelve animals discontinued from rinderpest experiments and inoculated with
20 c. c. of theileriasis blood ten succumbed to the disease, whereas, as already stated, the
disease was not fatal in the six healthy hill bulls used in the present investigation after
inoculation with equal quantities of blood obtained from the same control animals.
It has been observed by Sen and Srinivasan [1937] that the changes occurring in the
blood of an affected animal following the appearance of schizonts in the peripheral blood
afford a reliable clue to its chances of recovery. In all four reactors in the present inves-
tigation the first noticeable change in the blood was the occurrence of anisocytosis, dominated
later by polychromatophilia and usually associated with basophilia, whilst it was not un-
common to find punctate degeneration of the nucleated red cells. It would appear that the
sequence of anaemic changes is of a rapidly progressive type, since all the changes des¬
cribed above can be seen within a week or less from the beginning of anisocytosis. The
restoration to normal of the blood picture is also rapid.
Samples of urine during the clinical and post-clinical periods were now and then
examined for the presence of haemoglobinuria, but in no instance was any trace of haemog-
lobin found on chemical examination nor were intact erythrocytes seen microscopically.
Somewhat voluminous tables showing the figures for blood counts are withheld for reasons of space
but are available for scrutiny at Mukteswar.