早期断奶对藏西北绒山羊背最长肌氨基酸和脂肪酸含量的影响

目的] 研究早期断奶对藏西北绒山羊背最长肌中氨基酸和脂肪酸含量的影响。方法] 将18只健康羔羊按照体重相近原则随机分为试验组和对照组,试验组在28日龄（D28）实施早期断奶,对照组在60日龄（D60）自然断奶,羔羊断奶后饲喂相同的代乳料至75日龄;从两组随机选取5只羔羊进行屠宰采样,对其背最长肌中氨基酸和脂肪酸指标进行测定分析。结果] 在藏西北绒山羊背最长肌中检测出17种氨基酸,包括赖氨酸、亮氨酸等7种必需氨基酸,天冬氨酸、精氨酸等10种非必需氨基酸。两组断奶羔羊肉中总氨基酸含量、必需氨基酸含量、非必需氨基酸含量均无显著差异（P>0.05）,28日龄断奶组羔羊肉中EAA/TAA、EAA/NEAA比值显著（P<0.05）高于60日龄断奶羔羊。共检测出29种饱和脂肪酸、不饱和脂肪酸,以棕榈酸和油酸含量最高,早期断奶对羔羊肉中饱和脂肪酸含量、单不饱和脂肪酸含量以及多不饱和脂肪酸含量影响不显著（P>0.05）。结论] 藏西北绒山羊羔羊肉中所含氨基酸和脂肪酸种类多、含量丰富,实施早期断奶、及早补充颗粒料对肉中脂肪酸和氨基酸含量无影响,且可提高EAA/TAA、EAA/NEAA比值,使其更符合FAO/WHO氨基酸评分模式;该试验可为藏西北绒山羊羔羊实施早期断奶、提高母羊的繁殖率提供参考。

Effect of Early Weaning on Contents of Amino Acids and Fatty Acids in Longissimus Dorsi of Tibet Cashmere Goats

Objective]To assess the effect of early weaning on contents of amino acids and fatty acids in longissimus dorsi of Tibet cashmere goats.Method]A total of 18 healthy goat lambs were randomly divided into two groups according to the principle of weight similarity.The lambs in the early weaning group were weaned on the 28 days of age,and those in the normal weaning group were weaned on the 60 days of age.All of the lambs were fed with the same milk replacer until the 75 days of age after weaning.Five lambs were randomly selected and slaughtered from each group for sampling,and then the indicators of amino acids and fatty acids in longissimus dorsi were determined and statistically analyzed.Result]A total of 17 kinds of amino acids were found in longissimus dorsi of Tibet cashmere goats,including 7 kinds of essential amino acids such as lysine and leucine,and 10 kinds of non-essential amino acids such as aspartic acid and arginine.There were no significant(P>0.05)differences in contents of total amino acids,essential amino acids and non-essential amino acids between the early weaning group and the normal weaning group,while the EAA/TAA and EAA/NEAA in the early weaning group were significantly(P<0.05)higher than those in the normal weaning group.A total of 29 kinds of saturated and unsaturated fatty acids were detected,among which,the contents of palmitic acid and oleic acid were the highest.No significant(P>0.05)differences in contents of saturated fatty acids,monounsaturated fatty acids and polyunsaturated fatty acids between the early weaning group and the normal weaning group were observed.Conclusion]The meat of Tibet cashmere goat lamb has good performance in composition and contents of amino acids and fatty acids.Early weaning and early supplementation of pellet feed have no effects on contents of amino acids and fatty acids in lamb meat,and can increase the value of EAA/TAA and EAA/NEAA,making it more consistent with the FAO/WHO amino acid scoring pattern.This study may provide references for applying early weaning in Tibet cashmere goat lamb and improving reproductive rate of the ewes.