不同精粗比饲粮对牦牛瘤胃内环境的影响  

Effects of feeds at different roughage to concentrate ratios on the rumen environment of yak

作　　者：孙光明 朱彦宾[1] 平措占堆[1] 洛桑顿珠 达娃央拉[1] 次旦央吉 姜南 巴桑旺堆[1] SUN Guangming;ZHU Yanbin;PINGCUO Zhandui;LUOSANG Dunzhu;DAWA Yangla;CIDAN Yangji;JIANG Nan;BASANG Wangdui(Institute of Animal Husbandry and Veterinary Medicine,Tibet Academy of Agricultural and Animal Husbandry Sciences,Lhasa 850000,China)

机构地区：[1]西藏自治区农牧科学院畜牧兽医研究所,西藏拉萨850000

出　　处：《畜牧与兽医》2022年第1期31-34,共4页Animal Husbandry & Veterinary Medicine

基　　金：西藏自治区科技计划项目(XZ201901NA02);国家肉牛牦牛产业技术体系岗位专家项目(CARS-37);省部共建青稞和牦牛种质资源与遗传改良国家重点实验室项目(XZNKY-2020-C-007Z06)。

摘　　要：旨在研究不同精粗比饲粮对西藏牦牛瘤胃内环境的影响。选取3周岁、平均体重(154.8±13.6)kg、健康无病的牦牛20头随机分为低精料组和高精料组,每组10头,公母各半,分别饲喂低精料(精粗比40∶60)和高精料(精粗比60∶40)饲粮,预试期10 d,正试期90 d(8、9和10月)。结果:饲粮精料水平的提高显著降低了瘤胃pH值、异丁酸和异戊酸占总挥发性脂肪酸(TVFA)的百分比(P<0.05),显著增加了瘤胃TVFA含量(P<0.05),但乙酸、丙酸、丁酸、戊酸占TVFA的百分比及乙酸/丙酸值不受饲粮精粗比的影响(P>0.05);饲粮精料水平的提高显著提高了瘤胃氨态氮(NH_(3)-N)和总氮(TN)含量(P<0.05),显著降低了微生物蛋白(MCP)含量(P<0.05)。研究表明,饲喂低精料饲粮有利于促进牦牛氨态氮的利用与微生物蛋白的合成,改善瘤胃氮平衡。This study was to understand how the rumen environment of Tibetan yaks was affected by diets formulated with different roughage to concentrate ratios(R∶C).Twenty healthy yaks,aged 3 and with similar body weight(154.8±13.6)kg,were selected and then assigned to a low-concentrate group and a high-concentrate group(10 animals per treatment,half males and half females),using a randomized block experimental design.The diets were the low-concentrate diet at an R∶C ratio of 60∶40 and the high-concentrate diet at an R∶C ratio of 40∶60.A pre-experimental period lasted for 10 days and the formal experimental period lasted for 90 days(August,September and October).The results showed as follows:1)A high concentrate level in diet significantly decreased the ruminal pH,and the percentage of isobutyric acid and isovaleric acid in the total volatile fatty acid(TVFA)in the yaks(P<0.05),but increased their ruminal TVFA(P<0.05).However,the percentages of acetic acid,propionic acid,butyric acid and valeric acid in TVFA and the acetic acid/propionic acid value were not affected by the roughage to concentrate ratios(P>0.05).2)When the concentrate level was higher in the diet,the contents of ruminal ammonia nitrogen(NH_(3)-N)and total nitrogen(TN)were higher and the content of ruminal microbial protein(MCP)was lower,in the yaks(P<0.05).Therefore,a low-concentrate diet was more helpful for yaks to better utilize ammonia nitrogen and synthesize microbial proteins,achieving a better nitrogen balance in their rumens.

关 键 词：牦牛 精粗比 瘤胃发酵 氮平衡 

分 类 号：S823.5[农业科学—畜牧学]