不同蛋白质水平日粮中添加2-羟基-4-(甲硫基)丁酸异丙酯对奶牛生产性能及血液生化指标的影响  

Effect of 2-hydroxy-4-(methylthio) butanoic acid isopropyl ester(HMBi) supplementation of diets with different protein levels on milk production and serum parameters in dairy cows

作　　者：王群[1] 尹军力 唐波[1] 韩兆玉[1] 

机构地区：[1]南京农业大学动物科技学院,江苏南京210095 [2]南京红山森林动物园,江苏南京210028

出　　处：《南京农业大学学报》2014年第3期126-132,共7页Journal of Nanjing Agricultural University

基　　金：国家科技支撑计划项目(2012BAD12B10)

摘　　要：根据年龄、胎次、泌乳时间、产奶量相近的原则选择40头泌乳前期荷斯坦奶牛,随机分成试验Ⅰ、Ⅱ、Ⅲ、Ⅳ组,每组10头,在相同条件下饲养。试验Ⅰ组饲喂170 g·kg-1蛋白质水平的日粮,试验Ⅱ组在试验Ⅰ组基础上添加29.9 g·d-12-羟基-4-(甲硫基)丁酸异丙酯(HMBi),试验Ⅲ组饲喂160 g·kg-1蛋白质水平的日粮,试验Ⅳ组在试验Ⅲ组基础上添加29.9 g·d-1HMBi。每天饲喂3次,挤奶3次。结果表明:2个蛋白质水平下添加HMBi产奶量均有所提高,试验Ⅱ组比试验Ⅲ组升高了2.09 kg·d-1(P<0.05);2个蛋白质水平下添加HMBi有提高乳脂率、乳糖含量、乳蛋白率和降低乳尿素氮含量的趋势;170g·kg-1蛋白质水平下添加HMBi(试验Ⅱ组)能够降低体细胞数,与试验Ⅰ组相比,差异显著(P<0.05),160 g·kg-1蛋白质水平下添加HMBi(试验Ⅳ组)有降低体细胞数趋势,差异不显著(P>0.05)。血清甘油三酯(TG)、血糖(GLU)、血清尿素氮(BUN)和游离脂肪酸(NEFA)在试验前后各组间差异不显著。2个蛋白质水平下添加HMBi可以提高血清超氧化歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性,降低丙二醛(MDA)含量;对血清胰岛素样生长因子(IGF-1)、催乳素(PRL)胰岛素(INS)和瘦素(LEP)的浓度无显著影响。2个蛋白质水平下添加HMBi有提高奶牛采食量、奶料比的趋势。结论:在日粮中添加HMBi能提高奶牛生产性能及机体抗氧化能力,对奶牛营养物质代谢相关的代谢物质及激素水平有促进作用;添加HMBi的日粮中可以适当降低蛋白质水平,并不影响奶牛生产性能的发挥,同时有助于提高氮的利用。Forty Holstein cows were selected according to the principles of similar age,parity,lactation time and milk yield. They were randomly divided into 4 treatments with 10 cows in each treatment. TreatmentⅠwas fed the diet with 170 g·kg-1crude protein（CP）,treatment Ⅱ was fed the diet added with 2-hydroxy-4-（methylthio） butanoic acid isopropyl ester（HMBi） on the basis of treatmentⅠ,treatment Ⅲ was fed the diet with 160 g·kg-1CP level,and treatment Ⅳ was fed the diet added with HMBi on the basis of treatment Ⅲ. With per kilogram of feed supplement added with 2. 3 g HMBi,cows were fed and milked three times a day. Milk yield was measured twice a week. Mixed milk samples were collected one day a week,and were used for determination of content of milk fat,milk protein,lactose,non-fat solids,total solids,somatic cell count（SCC） and milk urea nitrogen（MUN）. Feed intake and feed dry matter rate were determined one day a week. Dry matter intake was calculated by feed intake×feed dry matter rate. At pretest and post-test,10 mL venous blood from the tails was collected from each cow. Serum was separated by centrifuge at 3 500 r·min-1and stored at-20 ℃ refrigerator for the analysis of blood-related parameters. Milk yield increased in the treatments added with HMBi,treatment Ⅱ increased 2. 09 kg·d-1than treatment Ⅲ,it was significant difference（P〈 0. 05）,but there was no significant difference between the other treatments（P〉0. 05）. Milk fat,lactose and milk protein increased and MUN decreased in the treatments added with HMBi,but there was no significant difference between treatments. Adding HMBi in 170 g·kg-1CP level significantly reduced SCC more than that of treatment Ⅰ（P 〈 0. 05）,adding HMBi in 160 g·kg-1CP level reduced the SCC,butshowed no significant difference. Triglycerides（TG）,glucose（Glu）,blood urea nitrogen（BUN） and nonesterified fatty acid（NEFA） had no significant difference between treatments before and after test. Serum superoxide dism

关 键 词：2-羟基-4-(甲硫基)丁酸异丙酯(HMBi) 奶牛 蛋白质水平 生产性能 血液指标 

分 类 号：S813.24[农业科学—畜牧学]