Dynamics of chicken blood leukogram in experimental staphylococcosis

Abstract

We have studied the impact of experimental staphylococcosis on the leukogram of Hisex Brown chickens. We divided the chicks into 3 groups, Group I assigned as control, Groups II and III – experimental. The chicks were challenged by intraperitoneal injection with Staphylococcus aureus (Group II) and Staphylococcus cohnii (Group III) at a concentration of 3 McFarland. The blood was drawn by cardiac puncture at days 1, 3, 5, 7, 9, 11 and 13 after the challenge. We studied the leukogram using stained blood smears. In the course of research we observed hematological parameters with lasting changes, which were more pronounced at days 1, 3, 5, 7 and 9 (in both experimental groups). We also observed an increase in the leukocyte count in the blood of chicks in Groups II and III, and a longterm pseudoeosinophilia along with monocytosis. We marked a decrease in the absolute lymphocyte count in both experimental groups, but the number returned to normal by the end of the experiment. The relative eosinophil count changed mostly in the blood of chicks in Group III, but the changes were insignificant. Basing on the data we have obtained during the experiment; we suggest that St. aureus exerts a toxic effect on the chicken organism in a greater degree than St. cohnii does.