Histopathological and haematological changes in haemonchosis caused by Haemonchus contortus in small ruminants of Bangladesh

Abstract

Haemonchosis is an endoparasitic infection of ruminants caused by Haemonchus parasites and causes economic losses in the production system in developing countries. Proper diagnosis is important for prevention and control strategies. The present study was conducted to observe the histopathological and hematological changes in Haemonchus infection in small ruminants (sheep and goats). A total of 50 gastrointestinal tracts and livers were collected from 50 slaughtered animals, and 17 samples were found positive for haemonchosis. These parasites were detected by morphometric features. In the histopathological section, all abomasa of the infected host (17) disclosed hemorrhages, edema, congestion of the blood vessels, and desquamation of abomasal villi. Lymphocytic and a huge amount of eosinophilic infiltration (52.94%) were found in the mucous and gastric glands of the abomasum. The liver showed congestion (17.64%), hepatocyte degeneration, bile duct hyperplasia, and mononuclear cell infiltration. A uniform basophilic calcified mass lined by a thick fibrous capsule was also observed in the liver. In the hematological study, the packed cell volume (%) significantly (P=0.005) declined (24.53±4.69) compared to the normal value (25-40%). The RBC (6.15±1.85 million/mm3) and Hb (8.40±0.92 g/dl) concentration were apparently lower than the normal values. Eosinophil (5.59±2.37%) and lymphocyte (78.11±9.71%) counts were apparently increased compared to their normal values (1-6% and 50-70%, respectively) in Differential cell count. These findings of the present study may upgrade the diagnostic tools for haemonchosis in small ruminants in Bangladesh.