Effect of pre-slaughter transport time on lamb quality

Pre-slaughter transportation is one of the most important factors affecting meat quality of livestock and poultry. Forty six-month-old rams, the hybrid of Ujimqin sheep and small-tail Han sheep, divided into four groups that were transportedfor0 h (control group), 1, 3, and 6 h before slaughter. The effect of pre-slaughter transport time on lamb quality was analyzed by evaluating the palatability, sensory characteristics, and protein content. The results showed that the pH and shear force values of lamb at 24 h after slaughter were significantly higher than those in the control group, where both had increased by 0.54% to 2.90% and 15.60% to 24.61%, respectively (P< 0.05). Pre-slaughter transport for 3 and 6 h caused an increase in ΔE value by 6.12% and 6.50%, respectively, and significantly reduced the overall acceptability score (via sensory evaluation) by 13.51% and 20.82% (P< 0.05), respectively. Cooking loss recorded in the group transported for 6 h before slaughter was lower than that in the control group, with a 7.37% decrease(P< 0.05). The lamb in the group transported for 1 h showed a lower degree of myofibrillar protein degradation than that observed in the other groups (P< 0.05). Thus, pre-slaughter transport for 1, 3, and 6 h showed a negative effect on lamb meat quality, to varying degrees. These results suggest that pre-slaughter transport should be avoided as much as possible or other pre-slaughter treatments should be employed to allow sheep to recover from transportation stress.