碳水化合物来源和棉粕添加水平对奶牛采食量、瘤胃发酵和微生物蛋白合成的影响  

Effects of carbohydrate sources and cottonseed meal levels on feed intake rumen fermentation and microbial protein synthesis in dairy cattle

作　　者：贾珺 郝宇卉 JIA Jun;HAO Yuhui(Xinzhou Vocational and Technical College,Xinzhou,Shanxi Province 034000,China)

机构地区：[1]忻州职业技术学院,山西忻州034000

出　　处：《中国饲料》2020年第14期62-65,共4页China Feed

基　　金：忻州职业技术学院2018年度院级课题(XZZY1804)。

摘　　要：本研究旨在探讨不同碳水化合物来源和棉粕对奶牛采食量、营养物质消化率、瘤胃发酵及微生物蛋白合成的影响。将4头6月龄的奶牛随机分配到4种日粮处理,日粮按照2×2因子设计,其中两个碳水化合物来源(木薯和木薯与米糠按照3:1混合),两个棉粕水平(109和328 g/kg),两组粗蛋白质水平均为490 g/kg。奶牛补充尿素-石灰处理的水稻秸秆,并按每千克体重补充10 g精料。结果发现:棉籽水平和碳水化合物来源和水平对瘤胃pH、氨氮浓度、微生物蛋白合成和采食量均无显著影响(P>0.05)。以木薯+米糠(3:1)作为碳水化合物来源时,与木薯处理组相比,干物质和有机物的消化率更高(P<0.05)。低棉粕水平组较高棉粕水平组显著提高了蛋白质消化率(P<0.05)。当木薯与米糠为3:1时,该组显著降低了丙酸和丁酸含量(P<0.05)。与3:1的木薯和米糠组相比,木薯组瘤胃细菌总数和蛋白水解菌数量均显著降低(P<0.05)。各处理对瘤胃微生物蛋白合成及合成效率均无显著影响(P>0.05)。因此,使用高水平的木薯和棉粕对奶牛瘤胃微生物种群的能氮平衡产生积极影响。The purpose of this study was to investigate the effects of different carbohydrate sources and cottonseed meal on feed intake,nutrient digestibility,rumen fermentation and microbial protein synthesis in dairy cows.Four 6-month-old cows were randomly assigned to a 2×2 diet with two carbohydrate sources(cassava and cassava mixed with rice bran at 3:1),two cottonseed meal levels(109 and 328 g/kg),and both groups of crude protein levels of 490 g/kg.Cows were fed rice straw treated with urea and lime,and 10 g concentrate per kilogram of body weight.The results showed that cottonseed level and carbohydrate source and level had no significant effect on rumen pH,ammonia nitrogen concentration,microbial protein synthesis and feed intake(P>0.05).When cassava+rice bran(3:1)was used as a carbohydrate source,the digestibility of dry matter and organic matter was higher than that of cassava treatment group(P<0.05).Protein digestibility was significantly increased in the low cotton meal group compared with the Khmer meal group(P<0.05).When cassava and rice bran were 3:1,the content of propionic acid and butyric acid in this group was significantly reduced(P<0.05).Compared with the cassava and rice bran groups at 3:1,the total number of rumen bacteria and proteolytic bacteria in the cassava group were significantly decreased(P<0.05).All treatments had no significant effect on rumen microbial protein synthesis and synthesis efficiency(P>0.05).Thus,the use of high levels of cassava and cottonseed meal had a positive effect on the energy and nitrogen balance of the rumen microbial population of cows.

关 键 词：碳水化合物 棉粕 奶牛 瘤胃发酵 微生物蛋白合成 

分 类 号：S823[农业科学—畜牧学]