Incidence of bruising and dark firm dry beef in cattle carcasses in a commercial abattoir in Zimbabwe: an animal welfare concern

Abstract

The incidence of carcass bruising and occurrence of dark, firm, dry (DFD) beef in slaughter cattle were investigated from a survey of 9585 cattle delivered to a commercial abattoir. The objectives of the study were to evaluate the extent of occurrence of carcass bruising and DFD in slaughter cattle as these have a major impact on economic returns to the beef producer. In addition, these data can be used as indicators of either good or poor welfare of the animals prior to slaughter. In this study, the overall incidence of bruising was 29.6 percent while that of DFD was 27.4 percent. There were differences between the incidences of both bruising and DFD (p<0.001) in carcasses from bulls, steers and cows. Overall, bulls had the greatest carcass damage and steers the lowest. In addition, bruising increased (r = 0.97; p<0.05) and the incidence of DFD also increased (r = 0.94; p<0.05) with increasing transit distance. Linear regression analysis showed that a sixty kilometer increase in transit distance resulted in a seven percent increment in bruising (equation: y = 6.9 + 7.1 x; R2 = 0.96; p = 0.0047). However, there was no association between bruising and DFD. Among different carcass weights, there was considerable variation in frequency of occurrence of DFD (p<0.001), with the proportion of carcasses showing DFD decreasing as carcass weight increased. The results indicate substantial compromised animal welfare and major economic loss to the entire livestock industry. Further, the results suggest that transit distance appears to contribute substantially to causes of bruising and DFD in slaughter cattle in Zimbabwe.