Physiological Indices of Stress in Cattle During Slaughter Without Prior Stunning at an Abattoir in Bauchi State

The physiological stress associated with pre-slaughter handling and the slaughter procedure itself has animal welfare implications that are gaining increasing regulatory and scientific attention in Nigeria. In Bauchi State, North East Nigeria, the majority of cattle are slaughtered without prior mechanical stunning in accordance with halal requirements, which is the norm across most of the North. This study measured stress-related physiological parameters in cattle presented for slaughter at the Bauchi Municipal Abattoir. Forty White Fulani cattle were enrolled, and blood samples were collected at three time points: upon arrival at the abattoir, following lairage of six hours, and immediately at slaughter. Cortisol, glucose, lactate, haematocrit, and fibrinogen were measured. Cortisol concentrations were significantly elevated upon arrival compared to reference values for cattle at pasture, and remained high after lairage, indicating persistent stress during the holding period. Glucose and lactate concentrations increased significantly from arrival to slaughter, consistent with activation of the hypothalamo-pituitary-adrenal and sympatho-adrenal axes. Haematocrit increased by a mean of 4.7 percentage points between lairage and slaughter, reflecting haemoconcentration from splenic contraction. Fibrinogen was elevated above baseline at slaughter. These findings suggest that lairage conditions and pre-slaughter handling at the Bauchi Abattoir contribute to significant physiological stress in cattle and highlight opportunities for welfare improvement through better lairage facilities and ante-mortem handling practices. Keywords: slaughter stress, cattle, cortisol, Bauchi, animal welfare.