日粮精料水平和蛋氨酸铬添加对滩羊瘤胃发酵特性、细菌和脂肪酸组成的影响  

Effects of dietary concentrate level and chromium-methionine supplementation on ruminal fermentation,and ruminal bacterial and fatty acid composition in Tan lambs

作　　者：金亚东[1] 赵海霞 桂瑞麒 马青 周玉香[1] JIN Ya-dong;ZHAO Hai-xia;GUI Rui-qi;MA Qing;ZHOU Yu-xiang(College of Agriculture in Ningxia University,Yinchuan 750021,China;Research Center of Grass and Livestock,Ningxia Academy of Agriculture and Forestry Science,Yinchuan 750002,China)

机构地区：[1]宁夏大学农学院,宁夏银川750021 [2]宁夏农林科学院动物科学研究所,宁夏银川750002

出　　处：《草业学报》2022年第2期192-202,共11页Acta Prataculturae Sinica

基　　金：宁夏高端滩羊肉生产关键技术研究与集成示范(2018BBF02016)资助。

摘　　要：为了研究日粮精料水平和蛋氨酸铬(Cr-Met)添加对滩羊瘤胃发酵参数、脂肪酸组成和细菌丰度的影响,选取40只体重相近[(21.00±1.23)kg,5月龄]且健康状况良好的滩羊公羔,随机分为4组,每组10只。LC组饲喂精粗比为35∶65的全混合饲粮,日粮中不添加Cr-Met;HC组饲喂精粗比为55∶45的全混合饲粮,日粮中不添加Cr-Met;HCM和HCH组均饲喂精粗比为55∶45的全混合饲粮,Cr-Met的添加量分别为0.75和1.50 g·d^(-1)·只^(-1)。在试验第65天晨饲后3 h通过各组滩羊口腔取瘤胃液,用于分析瘤胃发酵和瘤胃液脂肪酸组成以及细菌DNA的提取。结果表明:1)HC组滩羊瘤胃pH、乙酸比例和乙酸/丙酸显著低于LC组(P<0.05),但微生物蛋白(MCP)产量、丙酸和戊酸比例却显著高于LC组(P<0.05);与HC组相比,HCM组的乙酸/丙酸显著升高(P<0.05)。2)HC组反式油酸溶纤维丁酸弧菌和黄色瘤胃球菌的DNA丰度显著低于LC组(P<0.05),但解脂厌氧弧杆菌的DNA丰度却显著高于LC组(P<0.05);高精料日粮中添加Cr-Met线性降低了硬脂酸溶纤维丁酸弧菌、反式油酸溶纤维丁酸弧菌、蛋白溶解梭菌和解脂厌氧弧杆菌的DNA丰度(P<0.05),但黄色瘤胃球菌的DNA丰度却线性升高(P<0.05)。3)与LC组相比,HC组滩羊瘤胃内t11 C18:1(TVA)、trans C18:1、c9t11 CLA、t10c12 CLA、C18:2n6和C18:3n3的浓度显著降低(P<0.05),而C18:0的浓度则显著升高(P<0.05);高精料日粮中添加Cr-Met线性提高了TVA和trans C18:1的浓度(P<0.05)。综上所述,饲喂精粗比为55∶45的日粮抑制了部分氢化细菌的生长,Cr-Met的添加对机体共轭亚油酸的生成有一定的促进作用。This study evaluated the effects of dietary concentrate level and chromium methionine(Cr-Met)supplementation on ruminal fermentation and fatty acid composition,and ruminal bacteria abundance in Tan lambs.Forty male Tan lambs[(21.00±1.23)kg body weight,5 months of age]were randomly assigned to four treatment groups with 10 lambs in each treatment.The treatments were:a low-concentrate(LC)diet(concentrate∶forage,35∶65)without Cr-Met supplementation;a high-concentrate(HC)diet(concentrate∶forage,55∶45)without Cr-Met supplementation;groups fed the HC diet with 0.75 or 1.50 g·d^(-1)·lamb^(-1) Cr-Met(HCM and HCH,respectively).Ruminal fluid was collected on day 65 with an oral stomach tube about 3 h after the morning feed and samples used for fermentation analysis,fatty acid composition determination and bacterial DNA extraction.It was found that:1)Ruminal pH,acetate proportion and acetate∶propionate were greater(P<0.05)with the LC diet whereas microbial crude protein,propionate and valerate proportions were greater(P<0.05)with the HC diet.The acetate∶propionate was greater(P<0.05)in the HCM group than in the HC group.2)For the HC diet,the DNAabundances of Butyrivibrio fibrisolvens vaccenic acid subgroup(Butyrivibrio VA)and Ruminococcus flavefaciens were decreased(P<0.05),compared with the LC diet,whereas the DNA abundance of Anaerovibrio lipolytica was increased(P<0.05).For lambs fed the HC diet,DNA abundances of B.fibrisolvens stearic acid subgroup,Butyrivibrio VA,Butyrivibrio proteoclasticus,and A.lipolytica showed a linear decrease(P<0.05)with increasing Cr-Met supplementation level;However,the DNA abundance of R.flavefaciens showed a linear increase(P<0.05).3)Compared with the LC group,the concentrations of t11 C18:1,trans C18:1,c9t11 CLA,t10c12CLA,C18:2n6,and C18:3n3 were decreased by the HC diet without Cr-Met supplementation whereas the concentration of C18:0 was increased.There was a linear increase in t11 C18:1 and trans C18:1 with increasing CrMet supplementation level in lambs fed the HC diet.Th

关 键 词：滩羊 精料水平 蛋氨酸铬添加 瘤胃细菌丰度 脂肪酸 

分 类 号：S826.5[农业科学—畜牧学]