水牛瘤胃氮及矿物质代谢若干规律的研究

STUDIES ON THE METABOLISM OF NITROGEN AND MINERALS IN THE RUMEN OF SWAMP BUFFALO

试验采用４头装有永久性瘤胃瘘的本地生长雄性水牛。在秋季自由采食稻草或青干草日粮条件下，采用Ｃｒ─ＥＤＴＡ连续灌流标记法，测定瘤胃液的体积、周转率和停留时间，观察瘤胃氮、矿物质代谢水平和昼夜动态。结果表明，在这两种日粮条件下，瘤胃液的体积（ｆｌｕｉｄｖｏｌｕｍｅ）、周转率（ｔｕｒｎｏｖｅｒ ｒａｔｅ）和停留时间（ｒｅｔｅｎｔｉｏｎ ｔｉｍｅ）差异不显著。但瘤胃乙酸、丙酸、丁酸、氨氮（ＮＨ＿３－Ｎ）、细菌蛋白氮、以及Ｎａ￣＋、Ｃａ￣＋＋、Ｍｇ￣＋＋、Ｐ的浓度青干草期均显著高于稻草期（Ｐ＜０．０１），青干草期瘤胃ＮＨ＿３－Ｎ、细菌蛋白氮、丁酸、Ｃａ￣＋＋、Ｍｇ￣＋＋、Ｐ的绝对池量（ｐｏｏｌ）也均显著高于稻草期（Ｐ＜０．０１），但两期的发酵类型无明显变化。

In the experiment,four indigenous swamp buffaloes aging about one year old withrumen fistula were fed with hay or rice straw ad libitum in autumn.To determine fluidvolume,turnover rate and retention time in the rumen with the method of continuousinfusion of Cr-EDTA dissolved in water were used,and the metabolism of nitrogen andminerals,as well as the diurnal dynamics in the rumen,were also observed.The resultsshowed that the fluid volume,turnover rate and retention time were not significantlyaffected by the diets consumed.However,the concentrations of acetate,propionate,butyrate,NH_3-N and bacterial protein-N,as well as Na￣+,Ca￣++,Mg￣++ and P in therumen in the hay period were significantly higher than that in rice straw period.Thepools of NH_3-N,bacterial protein-N,butyrate,Ca￣++,Mg￣++ and P,when hay was fed,were significantly higher than those when rice straw was fed.But the type of rumenfermentation were not affected by the diets consumed.