Hemato-biochemical and pathomorphological alterations due to Mycobacterium avium subsp. paratuberculosis infection in goats

A study was conducted to evaluate the haemato-biochemical and pathomorphological alterations in goats due to Mycobacterium avium subsp. paratuberculosis (MAP) infection. Out of 818 faecal samples, 317 (38.75%) were found positive for MAP on Ziehl-Neelsen staining followed by its genomic confirmation for caprine paratuberculosis by IS900 PCR using IS 900 gene specific primers. A total of 90 blood samples (negative controls=25, affected=65) were subjected to haemato-biochemical investigation. Pathomorphological studies were carried out on 20 tissue samples collected from MAP positive necropsied goats. Significant (P<0.05) decrease in haemoglobin, total erythrocyte count, packed cell volume and mean corpuscular haemoglobin and significant (P<0.05) increase in total leucocyte count with relative lymphocytosis were observed in MAP-infected goats. Aspartate aminotransferase, alanine transaminase, creatinine, blood urea nitrogen, sodium, potassium and chloride were significantly (P<0.05) increased whereas total protein, glucose, albumin, calcium and magnesium were decreased significantly (P<0.05) in MAP-infected goats. The lesions on necropsy were emaciation, dehydration, thickening and corrugations in the intestine suggestive of chronic enteropathy. Microscopic examination of tissues revealed chronic granulomatous inflammation with mononuclear cell infiltrations in intestinal mucosa. The study elucidated a comprehensive investigative approach on haematobiochemical and pathological changes in caprine paratuberculosis, which will be useful in limiting the spread of this hidden killer disease in ruminants in the Odisha state.