本试验旨在探究采精期不同精料补饲水平对牦牛种公牛生长性能、血清指标和精液品质的影响.试验选取25头体况良好、遗传背景一致、平均体重为(584.48±55.71)kg的牦牛种公牛,随机分为5个组,分别为Ⅰ组(对照组)、Ⅱ组、Ⅲ组、Ⅳ组和Ⅴ组,每组5头,单栏单饲.5组牦牛每天分别补饲1.00、1.75、2.50、3.25和4.00 kg精料.预试期15 d,正试期45 d.结果表明:1)牦牛种公牛总增重和平均日增重随精料补饲水平的升高呈线性升高(P＜0.05).2)牦牛种公牛血清总蛋白、甘油三酯、低密度脂蛋白胆固醇、尿素含量以及谷丙转氨酶活性含量随精料补饲水平的升高呈线性升高(P＜0.05).与对照组相比,Ⅳ组和Ⅴ组血清总蛋白和尿素含量显著提高(P＜0.05),Ⅲ组血清白蛋白含量显著提高(P＜0.05),Ⅴ组血清甘油三酯含量和谷丙转氨酶活性显著提高(P＜0.05).3)与对照组相比,Ⅲ组牦牛种公牛血清谷胱甘肽过氧化物酶活性显著提高(P＜0.05),Ⅴ组血清丙二醛含量显著提高(P＜0.05).4)与对照组相比,Ⅲ组牦牛种公牛血清白细胞介素-4含量显著提高(P＜0.05).5)牦牛种公牛精子密度和精子前向运动能力随精料补饲水平的升高呈线性升高(P＜0.01),其中Ⅲ组、Ⅳ组和Ⅴ组精子密度和精子前向运动能力均极显著高于对照组(P＜0.01),Ⅱ组精子密度和精子前向运动能力显著高于对照组(P＜0.05).综上所述,补饲精料会显著改善牦牛种公牛精液品质,但补饲过量会对机体脂肪代谢、肝脏功能、肾脏功能以及机体抗氧化能力造成不利影响;因此,建议采精期牦牛种公牛适宜精料补饲水平为每天2.50 kg.
Effects of Concentrate Supplementation Level on Serum Indices and Semen Quality of Yak Breeding Bulls during Sperm Collection
This experiment was conducted to investigate the effects of different levels of concentrate supple-mentation on growth performance,serum indices and semen quality of yak breeding bulls during semen collec-tion.Twenty-five yak breeding bulls with good body condition,consistent genetic background and average body weight of(584.48±55.71)kg were randomly divided into 5 groups as group Ⅰ(control group),groupⅡ,group Ⅲ,group Ⅳ and group Ⅴ,with 5 yaks in each group,and each yak was fed in a single pen.The yaks in the five groups were supplemented with 1.00,1.75,2.50,3.25 and 4.00 kg concentrate per day,re-spectively.The pre-trial period lasted for 15 days and the experimental period lasted for 45 days.The results showed as follows:1)the total weight gain and average daily weight gain of yak breeding bulls were linearly increased with the increase of concentrate supplemental level(P＜0.05).2)The contents of total protein,tri-glyceride,low-density lipoprotein cholesterol and urea as well as alanine transaminase activity in serum of yak breeding bulls were linearly increased with the increase of concentrate supplemental level(P＜0.05).Compared with the control group,the serum total protein and urea contents in groups Ⅳ and Ⅴ were significantly in-creased(P＜0.05),the serum albumin content in group Ⅲ was significantly increased(P＜0.05),and the ser-um triglyceride content and alanine transaminase activity in group Ⅴ were significantly increased(P＜0.05).3)Compared with the control group,the serum glutathione peroxidase activity of yak breeding bulls in groupⅢ was significantly increased(P＜0.05),and the serum malondialdehyde content in group Ⅴ was significantly increased(P＜0.05).4)Compared with the control group,the serum interleukin-4 content of yak breeding bulls in group Ⅲ was significantly increased(P＜0.05).5)The sperm density and sperm forward motion abili-ty of yak breeding bulls were linearly increased with the increase of concentrate supplement level(P＜0.01),and the sperm density and sperm forward motion ability in groups Ⅲ,Ⅳ and Ⅴ were extremely significantly higher than those in the control group(P＜0.01),and which in group Ⅱ were significantly higher than those in the control group(P＜0.05).In conclusion,the concentrate supplementation can significantly improve semen quality of yak breeding bulls,but excessive supplementation has adverse effects on body fat metabolism,liver function,kidney function and antioxidant capacity.Therefore,it is suggested that the optimal concentrate sup-plement level for yak breeding bulls during semen collection is 2.50 kg per day.[Chinese Journal of Animal Nutrition,2024,36(7):4400-4412]
万方数据
维普
