Pre-slaughtering factors related to bruises on cattle carcasses

Abstract

The objective of the study was to determine the factors related to beef cattle carcass bruises. Handling, transportation and unloading data from cattle purchased by a slaughterhouse in southern Brazil were obtained to assess their associations with carcass bruising (occurrence or not) and the number of bruises per load. In total, 4338 carcasses from 142 loads of cattle purchased by the company were assessed. The females were cull cows and the males were steers. Independent variables studied included sex (females or males), loading facilities (good, regular or poor), cattle handling (good, regular or poor), transport time from the farm to the slaughterhouse (hours), hauling-truck types, truck animal-load density (kg/m2) and slaughterhouse unloading time (min). For both traits studied (carcasses bruised and number of bruises per load), all of the independent variables showed a significant (P < 0.05) effect. Animal sex is the most important factor on carcass bruising and the number of bruises per load, with females showing 91% more bruises than males. Moderate load densities caused greater bruising than did low (<370 kg/m2) and high (>431 kg/m2) densities. In general, greater bruising was caused by longer transport and unloading times. Bruises were reduced by improving loading facilities from regular to good. Transportation in vehicles with higher load capacities (animal numbers) resulted in greater bruising. Therefore, special handling practices and personnel training measures should be undertaken to mitigate losses pre-slaughter, especially when handling female cattle, which are more vulnerable to developing carcass bruises, possibly due to higher cow reactivity.