26
serum gives rise to an " anti-rabbit-brain " amboceptor in the serum of the goats which is capable
of being complemented by fresh sheep serum.
This also occurs when normal rabbit brain is employed for the injections. The serum of a
goat which had received 1/390 of its weight of normal rabbit brain substance subcutaneously and
the serum of an untreated goat were kept for 52 days on ice to destroy the complement and to
fall into line with a previous experiment. The serum of the treated goat was found to contain
an anti-rabbit-brain amboceptor which was complemented by sheep serum, whereas the untreated
goat serum contained none. It made no difference whether normal rabbit brain or fixed virus
brain was used for preparing the emulsions for this experiment.
8. Hi s t ol ogy OF THE BLOOD I N RABI ES .
BY
M. KESAVA PAI.
There is no appreciable change in the number of red and white corpuscles. Enumeration
with Gower's hæmocytometer shows that the average number of erythrocytes in a normal rabbit's
blood is 7,548,000 per cubic millimetre, the counts ranging between 6,056,000 and 8,560,000.
The high counts are very likely due to the altitude of Coonoor, about 6,000 feet above sea level.
Daily enumerations commencing from the day of subdural inoculation with fixed virus up to
the date of death gave counts varying between 7,016,000 and 8,320,000, the number bearing no
noticeable relationship either to the period which had elapsed after the inoculation or to the
stage of the disease. The average of the daily enumerations from the date of inoculation to
death gave 7,741,000 per c. mm. as compared with 7,548,000, the normal count.
Similarly the number of leucocytes which averaged 9,583 per c. mm. (ranging between 7,440
and 12,000) in health showed no definite increase or decrease after subdural inoculation, the
mean of the daily counts after the operation being 9,485 per c. mm. (counts ranging from 7,320 to
12,480). Here too as in the case of erythrocytes no relationship could be traced between the
daily leucocyte enumerations and the stage of the disease.
An important change, however, occurs in the relative proportions of the different types of
leucocytes. About the time that the initial signs of rabies manifest themselves the polymor-
phonuclear elements begin to show an increase and the small mononuclears a diminution in their
numbers, so that by the time the disease has well advanced the ratios in which these two types
of leucocytes exist in the blood are, as it were, reversed. Thus the polymorphonuclears which
form 27 per cent. of the total leucocytes in health average 45•8 per cent. when paralysis sets in
and 68•4 per cent., 70•9 per cent. and 69•7 per cent., respectively, 24 hours, 48 hours and 72
hours after the onset of paralysis. On the other hand, the small mononuclears which form on an
average 62•3 per cent. of the total white corpuscles in health decrease to 45•2 per cent. with the
onset of the initial symptoms, the percentage going further down to 23•2, 19•2 and 22, respec-
tively 24 hours, 48 hours and 72 hours after paralysis sets in. The following table shows the
relative proportions of the different types of leucocytes of the rabbit in health and after the
onset of rabies :—
TABLE No. 12.
Percentage in
health.
Type of leucocyte.
Percentage on
first day of
paralysis.
Percentage on
second day of
paralysis.
Percentage on
third day of
paralysis.
Percentage on
fourth day of
paralysis.
Small mononuclears
...
45•2
23•2
19•2
22
65•2
Polymorphonuclears* ...
45•8
68•4
70•9
69•7
27
Large mononuclears
...
3•8
3•6
4 • 1
2•6
3•7
Transitionals
...
. .
2•8
3•5
3•8
3•8
2•3
Basophile
poly morpho
nuclear
.
2•4
1•3
1•9
1 • 9
1•4
Eosinophiles* ...
...
..
...
• 1
•••
•4
An exactly similar change is noticed in the relative proportions of the leucocytes of
guinea-pigs in experimental rabies (vide Table No. 13).
* The polymorphonuclears in the rabbit contain fine round eosinophile granules in the protoplasm staining a deep
pink with Leishman. The eosinophiles show large round granules staining a light pink.