Animals developed leukocytosis (16.0109:l) at
the late stages of disease (Fig. 2A). The percentage of
segment neutrophils increased from day 7 to day 10 and
decreased drastically on day 11. Marked vacuolization
of the neutrophils was detected beginning from day 8–9
(Fig. 3 A, B, C). The number of stab neutrophils,
eosinophils and basophils were stable during the disease.
No band neutrophils were detected. The number
of lymphocytes exceeded the normal levels on day 1–2
and at the terminal stage of the disease. In this process,
juvenile lymphocytes poorly distinguishable from
monocytes appeared in blood on day 3 (singlecells) and
on days 9–11 when their amount reached 75% of total
lymphocyte count (Fig. 3D).