尿素-麻饼型日粮条件下绵羊瘤胃内烟酸产生、消失及流通规律研究

选用3只体重为35-43 kg安装永久性瘤胃痿管、十二指肠近端瘘管的内蒙古半细毛羯羊,在饲喂尿素-麻饼型日粮条件下,通过非同位素Co标记烟酸的启动-连续灌注方法,测定绵羊瘤胃烟酸的基本产生、消失、外流速率及十二指肠的流通速率。试验结果表明:饲喂尿素-麻饼型日粮的绵羊瘤胃烟酸的基本产生速率为2．92 mg/h。通过灌注的方法提高烟酸产量后,烟酸在瘤胃内的产生速率为5．62 mg/h;消失速率为2．65 mg/h;瘤胃内烟酸的外流速率为2．97 mg/h;同时得出烟酸在十二指肠的流通速率为1．74 mg/h。

Study on Some Dynamic Indices of Niacin in Rumen of Sheep Fed Urea-Linseed Meal Diet

Three growing-finishing sheep fitted with rumen and duodenum cannulas with body weight of 35-43 kg were used. They were fed Urea-Linseed meal based diet. A pulse-continuous buffer solution with nonlabeled niacin was introduced into the rumen of sheep to reach and keep steady state of the rumen, basal niacin production rate, disappearance rate, passage rate in the rumen and passage through the duodenum and other rumen liquid phase indices were determined. The results indicated: when sheep were fed soybean meal based, basal rumen niacin production rates were 2.92 mg/h; Daily niacin production rates were 5.62 mg/h, niacin disappearance rates were 2.65 mg/h, passage rates out the rumen were 2.97 mg/h and passage rates into the duodenum were 1.74 mg/h.