Abattoir-based prevalence of avian tuberculosis in chicken slaughtered at Poultry abattoir in Bishoftu, Central Ethiopia

Abstract

A cross-sectional abattoir-based study was conducted in apparently healthy chicken in Bishoftu town, Ethiopia to estimate the prevalence of avian tuberculosis and isolate its causative agent. The occurrence of avian tuberculosis was investigated using postmortem examination, bacteriological culture and acid-fast staining methods. Of the total 648 chicken examined to detect avian tuberculosis, 42 tissue samples showing gross pathological tuberculous-like lesions were collected from liver, spleen and intestine. The overall prevalence of avian tuberculosis in poultry was 6.48% (42/648) (95%CI: 4.53-8.38) on the basis of detailed postmortem examination. Out of 42 tissue samples cultured on Lowenstein-Jensen medium, 14 (33.3%) were bacteriologically culture positive and showed growth of dough-shaped smooth colony characteristic and out of these 14 culture positive samples, 5 (35.7%) were acid-fast positive mycobacteria. Statistical significant difference was observed in the prevalence of avian TB among chicken with different body condition scoring (χ2 = 23.593, p =0.001). Multivariable logistic regression analysis for risk factors showed that body condition scoring has a high statistical significant association with the prevalence of avian tuberculosis in the study area (p<0.05). Poor body conditioned chicken were more likely to show TB lesions (OR=4.45, 95% CI, 2.33- 8.52) than good body conditioned chicken. The present preliminary study on avian TB using postmortem lesion examination and microbiological methods revealed the occurrence of avian TB in low prevalence inapparently healthy chicken originated from intensive poultry farms in Bishoftu area; hence detail poultry meat inspection should be practiced at poultry abattoirs in order to reduce the public health risk.

Keywords: Abattoir, Avian tuberculosis, Postmortem examination, Poultry, Ethiopia