Studies on experimental coli bacillosis in chicks.

摘要

This study was conducted to investigate the clinical signs and haematological, gross and histopathological changes in chicks experimentally infected with Escherichia coli MTCC 294. A total of 50 chicks were divided into 2 groups: group I (control) and group II (infected with 0.2 ml of 1x108 c.f.u/ml of E. coli). The major clinical signs observed in infected chicks were dullness, depression, huddling and diarrhoea. At 24 and 48 h postinfection, a significant decrease in the mean values of haemoglobin (Hb) and mean corpuscular haemoglobin count (MCHC) was observed. The mean values of packed cell volume (PCV) and mean corpuscular volume (MCV) increased significantly at both intervals. Total erythrocyte count (TEC) did not show any significant variation. Marked leukocytosis associated with heterophilia and lymphocytopenia was observed in infected chicks at 24 and 48 h postinfection. Impression smears of liver and spleen revealed Gram negative rods. The infected group showed petechiae on epicardium, enlargement of liver with necrotic foci, congestion of spleen, kidneys and intestines and catarrhal exudation in lumen..