不同添加比例发酵桑叶饲粮对湘东黑山羊生长性能、血清指标及肌肉氨基酸、脂肪酸含量的影响

Effects of Different Adding Proportions of Fermented Mulberry Leaves on Growth Performance,Serum Indexes,Muscle Amino Acid and Fatty Acid Contents of Xiangdong Black Goats

本试验旨在研究不同添加比例发酵桑叶饲粮对湘东黑山羊生长性能、血清指标以及肌肉氨基酸、脂肪酸含量的影响。选取20只4月龄、健康且体重相近的湘东黑山羊羯羊,随机分为4组,每组5个重复。试验组饲粮含10%(LG组)、20%(MG组)和30%(HG组)的发酵桑叶,对照组饲粮不含发酵桑叶(CG组)。预试期10 d,正试期92 d。结果显示:1)试验组干物质采食量显著高于CG组(P<0.05),MG和HG组平均日增重比CG组分别提高了18.70%、43.40%,但组间差异不显著(P>0.05);试验组屠宰率显著高于CG组(P<0.05)。2)肌肉pH_(45min)、剪切力和失水率组间差异不显著(P>0.05);LG、HG组肌肉滴水率和熟肉率显著高于CG和MG组(P<0.05)。3)试验羊血清生化指标和免疫指标组间差异不显著(P>0.05);LG、MG组血清中丙二醛(MDA)含量显著低于CG组(P<0.05),HG组血清总抗氧化能力(T-AOC)显著低于CG、LG和MG组(P<0.05)。4)LG组肌肉中必需氨基酸和主要鲜味氨基酸含量显著低于CG、MG和HG组(P<0.05);MG组肌肉中肉豆蔻酸(C14∶0)含量显著高于其他组(P<0.05),但其他饱和脂肪酸含量组间差异不显著(P>0.05);肌肉中单不饱和脂肪酸含量组间差异不显著(P>0.05);HG组肌肉中γ-亚麻酸甲酯(C18∶3n3)、二十碳三烯酸(C20∶3n6)、花生四烯酸(C20∶4n6)等多不饱和脂肪酸含量显著高于CG、LG和MG组(P<0.05)。由此可见,添加适宜比例发酵桑叶饲粮能提高湘东黑山羊的采食量、屠宰性能和机体的抗氧化性能,改善肉品质,并促进肌肉中氨基酸和脂肪酸的沉积,建议饲粮中发酵桑叶的添加比例为20%。

This experiment was conducted to investigate the effects of different adding proportions of fermented mulberry leaves on growth performance,serum indexes,muscle amino acid and fatty acid contents of Xiangdong black goats.A total of 20 four-month-old Xiangdong black goats were randomly divided into 4 groups with 5 replicates per group.Goats in 4 groups were fed diets supplemented with 0(CG group),10%(LG group),20%(MG group),and 30%(HG group)fermented mulberry leaves,respectively.The pre-experimental period was 10 days,and the experimental period was 92 days.The results showed as follows:1)the dry matter intake(DMI)in CG,LG,HG groups was significantly higher than that in CG group(P<0.05).The average daily gain(ADG)in MG and HG groups was increased 18.70%and 43.40%than CG group,respectively,but there was no significant difference among all groups(P>0.05).The carcass yield in experimental groups was significantly higher than that in CG group(P<0.05).2)There were no significant differences in muscle pH_(45min),shear force and water loss rate among all groups(P>0.05).The muscle drip rate and cooked meat rate in LG and HG groups were significantly higher than those in CG and MG groups(P<0.05).3)There were no significant differences in serum biochemical indexes and immune indexes among all groups(P>0.05).The content of malonaldehyde(MDA)in serum in LG and MG groups was significantly lower than that in CG group(P<0.05),the serum total antioxidant capacity(T-AOC)in CG,LG and MG groups was significantly higher than that in HG group(P<0.05).4)The essential amino acid and main umami amino acid contents in muscle in LG group were significantly lower than that in CG,MG and HG groups(P<0.05).There were no significant differences of saturated fatty acid and monounsaturated fatty acid contents in MG group(P<0.05).The contents of polyunsaturated fatty acids which including methyl-γ-linolenic acid(C18∶3n3),eicostrienoic acid(C20∶3n6)and arachidonic acid(C20∶4n6)in HG group were significantly higher than those in CG,LG and MG groups(P<0.05).In conclusion,fermented mulberry leaves can improve dry matter intake,slaughter performance,antioxidant performance and meat quality of Xiangdong black goats,and promote the deposition of amino acids and fatty acids in muscle.It is recommend that the optimal adding level of fermented mulberry leaves in diets is 20%.