自然放牧条件下不同月龄的苏尼特羊屠宰性能和肉品质的比较研究OA

This experiment aimed to investigate the effects of slaughter age on the slaughter performance,meat quality,and serum biochemical indices of Sunit sheep under natural grazing conditions.A total of 24 Sunit castrated rams on the same natural pasture were selected for slaughter,with eight each at 8-month-old,24-month-old,and 36-month-old.The results showed that compared with the 8-month-old,the serum total protein(TP)and low-density lipoprotein cholesterol(LDL-C)concentrations in 36-month-old castrated rams were significantly increased(P<0.05),while the inorganic phosphorus(PHOS)content was significantly decreased(P<0.05).The slaughter performance of the 8-month-old and 24-month-old was lower than that of the 36-month-old.Regarding meat quality,with increasing age,the shear force of longissimus dorsi muscle tend to increase(P>0.05),the water loss rate and meat color brightness(L*)value were significantly higher than those of 24-month-old and 36-month-old(P<0.05),and the redness(a*)value was significantly lower than that of 24-month-old and 36-month-old(P<0.05).The slaughter age had no significant effect on the pH value,drip loss,steaming loss,and yellowing(b*)value of meat from the castrated rams(P>0.05).The study shows that with increasing of months of age,the serum TP and LDL-C levels in Sunit sheep increase,while PHOS content decreases.Furthermore,slaughter performance improves,but the tenderness of the longissimus dorsi muscle decreases,and the meat color darkens.