不同尾型绵羊生产性能、屠宰性能、肉品质和脂肪酸组成的比较

为了研究不同尾型绵羊生产性能、屠宰性能、肉品质和脂肪酸组成的差异,选择相同饲养管理水平下8月龄兰州大尾羊(Lanzhou fat-tailed sheep)、小尾寒羊(Small-tailed han sheep)、藏羊(Tibetan sheep)的羯羊各6只,测定生产性能后进行屠宰试验,检测尾部脂肪的脂肪酸组成,并将生产性能与屠宰性能指标进行相关性分析。结果表明:兰州大尾羊的体长、体高和尾型相关指标极显著高于小尾寒羊和藏羊,兰州大尾羊和藏羊的胸围、胸深、胸宽、尻宽显著高于小尾寒羊;兰州大尾羊的宰前活质量和胴体质量显著高于藏羊,极显著高于小尾寒羊;兰州大尾羊和藏羊的屠宰率比小尾寒羊分别极显著高出15.50%和15.62%,净肉质量和骨质量显著高于小尾寒羊;小尾寒羊肉的剪切力为(0.30±0.12)kg·f,极显著低于兰州大尾羊和藏羊。3种羊尾部脂肪中共检测到36种脂肪酸,小尾寒羊的饱和脂肪酸相对质量分数极显著高于兰州大尾羊和藏羊,不饱和脂肪酸相对质量分数极显著低于兰州大尾羊和藏羊。兰州大尾羊的体高与宰前活质量、眼肌面积呈极显著正相关,胸深与宰前活质量、胴体质量、净肉质量和眼肌面积呈显著正相关。3个品种羊宰前活质量与胴体质量、净肉质量等产肉力指标呈显著正相关。表明在相同舍饲营养水平下,3个品种羊生产和屠宰性能综合表现为:兰州大尾羊藏羊小尾寒羊,藏羊的肉质表现出失水率低、肉色深、剪切力大、熟肉率高等特点,兰州大尾羊的尾部脂肪营养价值最高。

Growth and Slaughter Performance,Meat Quality,and Fatty Acid of Sheep with Distinct Tail Types

The aim of this study was to investigate differences among growth performance,slaughter performance,meat quality,and fatty acid composition in sheep with distinct tail types.Six Lanzhou fat-tailed sheep(LFTS),small-tailed han sheep(STHS),and Tibetan sheep(TS),which were eight months old and fed the same diet,were respectively selected.Sheep were tested for growth performance and then were slaughtered.Composition of fatty acid in the tail was detected.The correlation between growth performance and slaughter performance was analyzed.The results showed that body length,body height,and tail-related indicators of LFTS were extremely significantly higher than those of STHS and TS; in addition,chest girth,chest depth,chest width,and rump width of LFTS and TS were significantly higher than those of STHS.Live and carcass mass of LFTS were significantly higher than those of TS,and were extremely significantly higher than those of STHS.Dressing percent of LFTS and TS were extremely significantly higher than that of STHS by 15.50% and 15.62%.Net meat and bone mass of LFTS were significantly higher than those of STHS.Tenderness of STHS was 0.30 ± 0.12,which was extremely significantly lower than that of LFTS and TS.A total of 36 fatty acids in the tail fat of the three types of sheep were detected.Relative mass fraction of saturated fatty acid in STHS was extremely significantly higher than that of LFTS and TS; in contrast,relative mass fraction of unsaturated fatty acid in STHS was extremely significantly lower than that in LFTS and TS.In LFTS,body height showed extremely significant positive correlation with live mass and rib eye area; significant positive correlations were found between chest depth and live mass,carcass mass,net meat mass,and rib eye area.In all three types of sheep,live mass was significantly positively correlated with the meat production indices,such as carcass mass and net meat mass.On the basis of these findings,we conclude that under the same feeding level,growth and slaughter performance of three sheep breeds was in the following order:LFTS-TS-STHS.TS meat exhibited low water rate,deep meat color,and high shear and cooked meat percentage,while LFTS had the highest nutritional value of tail fat.