The influence of source, sex class and pre-slaughter handling on the bruising of cattle at two slaughterhouses

Abstract

This study quantified potentially traumatic events during handling (350 groups; n = 3296), and the effect of source and sex class on the occurrence of carcase bruising of cattle (339 groups; n = 3270) at two commercial slaughterhouses. A mean of 0.13 and 0.97 potentially traumatic events per animal occurred during unloading and pre-stunning handling, respectively, predominantly hitting structures and gates. Use of driving instruments occurred at a rate of 1.4 contacts per animal during pre-stunning handling. Over 97% of carcases observed were bruised. Cattle from markets had more bruises (median 5.8, n groups = 103) than cattle transported to slaughter direct from farms (median 5.0, n groups = 236; P < 0.005). Sex class had a significant effect on the occurrence of potentially traumatic events and bruising. There were significant correlations between the occurrence of events during pre-slaughter handling and bruising to the rib (rs 0.473; P < 0.01) and butt (rs 0.219; P < 0.05). There were also significant correlations between the use of driving instruments and bruising on the forequarter (rs 0.160; P < 0.05), butt (rs 0.294; P < 0.01), back (rs 0.220; P < 0.01) and rib (rs 0.148; P < 0.05). Some differences between the slaughterhouses in the occurrence of events and bruising were probably due to the design of facilities and the handling procedures.