136
Study on the Haematology of Dogs in Health
was made and the first drop that oozed out without squeezing was taken up on a slide and spread
over another as rapidly and uniformly as possible. Giemsa stain gave good results. Immature
cells of lymphoblastic and myeloblastic origin were differentiated by the oxydase reaction in freshly-
prepared-blood smears. For this purpose the method recommended by Piney [1931] was generally
followed.
Films, immediately after air-drying were put in a glass stoppered jar containing 2 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 1 per cent solutions
of alpha-naphthol and paraphenylenediamine. They were then washed in distilled water and mounted
without drying in water glass, oxydase granules being stained blue. For the actual content of the
leucocytes the smears were mounted and examined by the method known as the 'Four field meander,
technique, and Arneth Index was taken for neutrophiles.
EXPERIMENTAL
From Table I it may be observed that compared with figures reported by various workers else-
where the average erythrocyte count per c.mm. of blood in the experimental dogs is within the
normal range of variation.
TABLE I
Blood-counts in healthy dogs
1. Prasad
.
.
.
.
2. Dukes (1935) . . .
3. Kohanawa (1928) . .
4. Gaiger & Davies (1938) .
5. Nicols (1935) . . .
Erythro-Leucocytes
cytes
(millions)
5.706
6.160
6.998
6.1
7.16
12570
12600
17050
13000
11068
Differential counts
Lym.
22.5
25
13.2
21
—
Neut.
61.9
57
77.4
64
—
Eosins.
9.3
10
3.3
9
—
Mono.
5.9
8
6.1
6
—
Baso.
0.4
0.0
—
—
—
While the count agrees closely with those of Duke's [1930], Gaiger and Davie [1938], it is slightly
below the figures reported by Kohanawa [1938] and Nichols [1935]. Similarly, the total white cell
counts and the differential counts differ to a certain extent from the figures mentioned by
Kohanawa, but are in close agreement with the figures reported by other workers.
Haemoglobin was estimated to be about 13.95 gm. per 100 c.c. of blood by weight. Figures
of other workers are not available for comparison.
General characters of the blood changes in infected dogs
The outstanding change in the blood of dogs infected with B. gibsoni is that of severe anaemia.
That there is a rapid fall in the red cell count as soon as the disease is fully established will be seen
from the figures for Dog No. 136, Table II.
The extreme anaemic condition apparently results in part from the disintegration of red corpuscles
heavily laden with parasites but chiefly from diminished activity of cell regenerating organs. The
first pathological appearance noticed is achromia, the red cells staining faintly owing to the general
lack of haemoglobin. This feature is constant and is soon followed by a series of other changes,
such as slight anisccytosis associated with polychromatophilia in which a varying number of immature
cells appear and which being deficient in. haemoglobin take a dirty blue tint. The proportion of
such cell ranges from 4 to 8 per cent depending upon the severity of the disease. Later, it is not
uncommon to find nucleated red cells and in very severe cases anisocytosis becomes very marked.
Punctate basophilia and punctate degeneration of red. cells or nucleated red cells, so commonly
observed in other species of animals in similar conditions are of rare occurrence in dogs.