Comparative Biochemical Evaluation of Liver Function in Poultry Slaughtered at Formal and Informal Abattoirs in Ibadan, Oyo State, South West Nigeria

Informal poultry slaughter points operating outside veterinary supervision in Nigerian markets raise food safety concerns related to undetected subclinical hepatic disease in poultry reaching the food chain. This study compared liver function biochemical indices in poultry slaughtered at formal and informal abattoirs in Ibadan, Oyo State, South West Nigeria. Two hundred and forty broiler chickens (one hundred and twenty per abattoir type) were sampled immediately ante-mortem. Blood collected from the jugular vein was analysed for alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, total bilirubin, and albumin. Post-mortem liver gross pathology and aflatoxin residue levels were determined in the same birds. Poultry from informal abattoirs demonstrated significantly elevated hepatic enzyme activities and higher total bilirubin compared to formally slaughtered birds. Gross hepatic pathology including enlargement, pallor, and petechiae was more prevalent among informally slaughtered birds at 34% versus 12% in formal abattoirs. Liver aflatoxin residue levels were detectable in 45% of informally sourced birds and 9% of formally sourced birds. These comparative findings provide empirical evidence of a substantial hepatic health disparity between formal and informal poultry supply chains in Ibadan and underscore the necessity of extending ante-mortem biochemical screening to informal poultry slaughter settings in South West Nigeria. Keywords: liver function, poultry, abattoir, aflatoxin, food safety.