异位酸调节断奶前后犊牛瘤胃及小肠黏膜发育机制研究

项目名称： 异位酸调节断奶前后犊牛瘤胃及小肠黏膜发育机制研究

项目编号： No.31272471

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 农业科学

项目作者： 刘强

作者单位： 山西农业大学

项目金额： 75万元

中文摘要： 国内外研究尚不能阐明断奶前后犊牛瘤胃及小肠黏膜发育的分子基础及其机制，尤其未能阐明瘤胃发育期间小肠代谢功能的应答机制。项目以断奶前后犊牛为研究对象，在日粮中添加不同水平异位酸（异丁酸、异戊酸或2-甲基丁酸），于断奶前、断奶时、断奶后屠宰采集样品，采用变性梯度凝胶电泳、16S和18S rRNA基因克隆文库、16SrRNA特异性探针定量杂交方法、生物显微技术、RT-PCR和Western blot技术，从分析瘤胃微生物区系、瘤胃及小肠黏膜组织形态学变化以及与瘤胃生酮作用和小肠葡萄糖吸收功能相关基因及蛋白质表达入手，揭示断奶前后犊牛瘤胃和小肠黏膜组织形态和代谢功能变化及支链挥发性脂肪酸调控机制，初步建立断奶前后犊牛瘤胃发育期间小肠葡萄糖吸收功能应答机制，为深入研究犊牛断奶前后瘤胃发育期间小肠应答机制奠定理论基础。

中文关键词： 异位酸；犊牛；瘤胃；小肠；黏膜

英文摘要： The molecular basis and mechanism of the development of rumen and small intestine mucosa in pre- and post-weaning calves is not clarified by researches at home and abroad, in particular, the response mechanism of intestinal metabolic function during rumen development is not yet clarified. The objective of this work is to investigate the effects of the isoacids on the regulation of the development of rumen and small intestine mucosa. One hundred and seventeen pre-weaning calves with similar body weight and 45 d after birth will be selected from three dairy cow farms, 39 calves per farm. Thirty-six calves in each farm will be allocated into four treatments at random. Graded levels (0, 3, 6, and 9 g/d) of isoacids (isobutyrate, isovalerate or 2-methylbutyrate) will be supplemented in the four treatments from day 45 to 120 after birth. Calves will be weaned at day 67 after birth. During the experiment period, calves will be slaughtered at 4 time intervals i.e. at day 45, 67, 90 and 120 after birth. Samples of ruminal liquid, tissue of rumen and small intestine mucosa will be collected at the same time. Rumen microbial diversity will be determined by using DGGE, 16S and 18S rRNA gene library. Rumen fiber-degrading bacteria will be quantitated by using quantitative 16S rRNA hybridization probes. Histological studies o

英文关键词： Isoacids；calves；rumen；intestine；mucosa