蛋氨酸对山羊十二指肠内源氮和氨基酸流量的影响

摘要

本试验研究了日粮添加蛋氨酸(Met)对山羊十二指肠内源氮(EN)和内源氨基酸(ENAA)流量的影响.采用3×3拉丁方试验设计,选用3头安装有永久性瘤胃、十二指肠近端瘘管和颈静脉插管、平均体重为(20±2.5)kg的健康湘东黑山羊为试验动物,饲喂3种Met水平分别为0.15%、0.25%和0.35%的试验日粮,采用同位素方法测定Met水平对山羊EN和EN从流量的影响.结果显示:当Met添加水平为0.15%时,十二指肠EN和ENAA流量均最低,但是无显著性差异(P>0.05).以上结果表明:日粮直接添加蛋氨酸对山羊十二指肠EN和ENAA流量没有显著影响作用(P>0.05),同位素稀释法测定反刍动物EN流量较为稳定.%The experiment was designed to study the effect of dietary methionine (Met) levels on duodenal flows of endoge-nous nitrogen (EN) and endogenous amino acids (ENAA) in growing goats fed normal protein-containing diets.Three goats with an average body weight of (20±2.5) kg were fitted with ruminal, duodenal cannulae and jugular veins polyvinyl cathe-ters, and allocated to three dietary treatments in a 3×3 Latin square design.The dietary treatments consisted of a total mixed diet containing three levels of Met which were 0.15%, 0.25% and 0.35%, respectively.EN and ENAA were deter-mined using isotope dilution method.The results showed that the duodenal flows of EN and ENAA were the lowest when the dietary Met level was supplemented at 0.15%, and there were no significant differences on duodenal flows of EN and ENAA (P>0.05).In conclusion, the duodenal flows of EN and ENAA were not significantly affected by the dietary direct supple-mentation of Met (P>0.05), and the isotope dilution method was relatively stable in determination of EN flow.