Pathological Study on Bovine Tuberculosis: A Survey Among Slaughtered Cattle and Buffalo in Menofiya Governorate During 2021-2022.

Bovine tuberculosis (bTB) is a chronic granulomatous disease that mainly affects the lungs and their lymph nodes. The proportion and pathological studies of bovine tuberculosis among slaughtered cattle and buffalo were determined in this study. Tissue samples from lymph nodes, lungs, heart, pleura, liver, and intestine were collected and rapidly fixed in 10% formalin for histopathology. This study was conducted on 91 cattle and 68 buffalo that revealed visible lesions of tuberculosis. The Gross lesion showed greyish-yellow cheese-like nodules in lymph nodes and internal organs. Microscopically, bTB is classified into miliary TB (9.37%) and localized TB (90.62%) in which granulomas were graded in four stages: Stage I (6.25%), Stage II (8.59%), Stage III (25%), and Stage IV (50.78%). Staining with Ziehl-Neelsen demonstrates acid-fast bacilli within the cytoplasm of macrophages, and giant cells and in the necrotic masses of TB granuloma. The higher proportion of bTB was recorded in cattle (59.34%) and buffalo (58.82%) aged 4-6 years. The sex-based proportion was higher in female buffalo (67.64%) than in males (32.35%), While in cattle, males (58.24%) had a greater frequency than females (41.75%). Data obtained from the Directorate of Veterinary Medicine, Shebin El Koom, Menofiya Governorate, revealed that the seasonal proportion of bTB was high during spring (8.5% cattle and 5% buffalo). The highest annual proportion of bTB was observed in 2022 (15.8% cattle and 9.8% buffalo) compared to 2021. Ashmon abattoir (76.5%) revealed a higher proportion, while El-Batanon (3.6%) had a lower proportion of bTB.