不同日粮对水牛复胃氮代谢的影响

EFFECTION OF DIFFERENT DIET TO NITROGEN METABOLISM OF BUFFALO’S STOMACH

选用２头装有长久性瘤胃瘘管和十二指肠瘘管的空怀水牛，比较研究舍饲稻草──混合精料（１期）与青刈草（２期）两种日粮条件下水牛复胃氮代谢的变化。结果表明：２期与１期比较，瘤胃液ｐＨ降低２．０２％（Ｐ＜０；０１），ＮＨ３－Ｎ提高２６６．９６％（Ｐ＜０．００１），微生物蛋白（ＭＣＰ）含量提高４８６．３６％（Ｐ＜０．００１）；昼夜十二指肠食糜ｐＨ增高２２．０６％（Ｐ＜０．００１），流量增加２３．３６％（Ｐ＞０．０５），总氮流量增高５２．０６％（Ｐ＜０．０５），非氨氮（ＮＡＮ）增加５３．３５％（Ｐ＜０．０１），ＭＣＰ氮增加１０１．８８％（Ｐ＜０．０１），饲料及内源性氮增加４４．２０％（Ｐ＜０．０５），ＮＨ３－Ｎ增加４７．６５％（Ｐ＞０．０５），尿素氮降低２３．３５％（Ｐ＞０．０５），昼夜食糜总氮流量与摄食总氮量之比下降１４．１３％（Ｐ＜０．００１），复胃有机物（ＯＭ）消化率提高２６．９０％（Ｐ＜０．０５），ＭＣＰ合成效率提高３４．８１％（Ｐ＞０．０５）。

Two female nonpregnent buffaloes installed with permanent rumen fistulae and duodenum fistulae were chosen inthis experiment to study comparatively changes of nitrogen nietablism in buffalo's stomach under the condition of straw-mixedconcentrate feeding(period 1)and the condition of forage feeding(period 2)respectively.Results of period 2,as compared withthat of period l:A,Buffalo's rumen fluid;Ammonia nitrogen(NH3-N)concentration increased by 266.96%(P<0.001);Mi-crobial protein(MCP) content increased by 486.36%(P<0.001);While pH value decreased by 2.02%(P<0. 01).B,Theduodenaldigesta round the clock:pH value lncreased by 22.06%(P<0.001);Digesta flow,by 23.36%(P>0.05);Total ni-trogen flow,by 52.06%(P<0.05); Nonammonia nitrogen(NAN),by 53.35%(P<0.01);MCP nitrogen,by 101.88%(P<0.01);Nitrogen of diet and endogenous nitrogen,by 44.20%(P<0.05 Ammonia nitrogen,by 47.65%(P>0.05);Theorganic matter digestibility,by 26.90%(P<0.05);MCP synthesis efficiency increased by 34.81%(P>0.05);While urea ni-trogen decreased by 23.35%(P>0.05);Ratio between total nitrogen flow of digesta and total nitrogen content of fed intake,decreased by 74.73%(P<0.001).