Gross pathological lesions of bovine tuberculosis and efficiency of meat inspection procedure to detect-infected cattle in Adama municipal abattoir

A cross-sectional study was conducted at Adama municipal abattoir from February 2010 to May 2011 to estimate the prevalence of bovine tuberculosis (BTB) and to evaluate the efficiency of meat inspection procedure to detect cattle infected with Mycobacterium bovis. The study only involved routine and detailed inspection at slaughter house. Chi-square test and test of agreement (Kappa value) were used to analyze the data. Out of 486 carcasses examined, 33 (6.79%) had lesions suggestive of tuberculosis. Routine abattoir inspection detected only 5 (15.15%) of 33 carcasses with visible lesion, and there was poor agreement (k = 0.14) between routine meat inspection and detailed post mortem examination. Anatomically, 67.7% of the lesions were found in lung and associated lymph nodes, 10.76% in mesenteric lymph node, and 9.2% in lymph nodes of the head and the remaining 12.3% were found in the prescapular, prefemoral and other lymph nodes and organs of the carcass. There was a significant difference (P < 0.05) in TB infection rate among different breeds, sex, and body conditions score (BCS). However, no significance difference (P > 0.05) was recorded between TB infection rate and ages of the animals. This study suggested that the relatively higher prevalence of BTB and low sensitivity of routine abattoir inspection warrant immediate attention.