Prevalence and pathology of paratuberculosis in cattle slaughtered at ELFORA export abattoir Bishoftu, central Ethiopia

Abstract Background Paratuberculosis, caused by Mycobacterium avium subsp. paratuberculosis (MAP), is a chronic progressive granulomatous enteritis affecting ruminants and a wide variety of domestic and wild life species worldwide. Although there are reports of clinical cases of paratuberculosis in different veterinary clinics in Ethiopia, there is no epidemiological data on this disease in Ethiopia. Thus, this study was formulated to investigate the prevalence and pathology of paratuberculosis in apparently healthy cattle slaughtered at ELFORA export abattoir. Small intestines and associated mesenteric lymph nodes of 400 cattle slaughtered at ELFORA export abattoir were examined for gross pathological lesions of paratuberculosis. The diagnosis was confirmed by histopathological examination. The microscopic lesions were then graded on the basis of the type and amount of cellular infiltrations. Results When the intestines and the corresponding lymph nodes were examined in the slaughterhouses the prevalence of paratuberculosis gross lesions was 11.25% (45/400). The gross lesions were characterized by intestinal thickening, mucosal corrugations and enlargement of associated mesenteric lymph nodes. Histopathologically 17.9% (8/45) of the cattle with gross lesion were found to have microscopic lesion compatible with paratuberculosis. The microscopic lesions were characterized by granuloma of different grades. The grading of the microscopic lesions revealed 2 animals had grade I, 4 grade II and 2 grade III lesions. Conclusions This study indicated the occurrence of paratuberculosis in cattle of Ethiopia using gross pathological examination of tissue samples. However, gross pathology alone cannot be used as a diagnostic tool and the findings stress the importance of a careful histopathological examination for confirmation of the gross lesions. We conclude that paratuberculosis is prevalent in cattle of Ethiopia for the first time and the result warrants for further nationwide study of the disease to establish its epidemiology and economic significance.