摘要
应用稳定同位素1 5 N 尿素示踪技术,经套颈圈禁食粪兔对日粮尿素的消化代谢试验表明:兔在禁食粪的条件下,尿素氮平衡值陡降至381±13 m g/d,利用系数锐减为80% ±04% ,严重地抑制了兔对日粮中尿素的利用;软粪中存留标记氮在兔利用日粮尿素中占有一定的地位,其中,微生物群随着食粪过程进入胃肠道中,将尿素和氨直接转化成菌体蛋白,从而增强了人们对兔利用尿素氮的机理与途径的认识。
Six 2 5 kg New Zealand male rabbits were selected to study the metabolism of urea N being utilized in rabbit using 15 N urea tracing technique.In order to prevent coprophagy,each rabbit had a collar in its neck.Basal diet which contained 16 01% of crude protein was fed to the rabbits for 120 g/d with additive 1% of 15 N urea(1 2 g).Results were showed as follows:① 15 N balance value in coprophagy prevented rabbits was 38 1±1 3 mg/d, 7 0%±0 3% to the 15 N urea uptake content,and utilization coefficient of 15 N was 8 0%±0 4%,about 39% to that of the normal rabbits.It could be seen that prevented corprophagy inhibited the utilization of 15 N in the diet.②Protein nitrogen in stomach and intestine of coprophagy prevented rabbits were 9 8% and 14 7%,14% and 23% to those of the normal rabbits,respectively.It could be inferred that microbiota in the normal rabbits played an important role on the transformation of 15 N urea to protein nitrogen.From study Ⅰ,Ⅱand Ⅲ it could be elucidated that:①rabbits could utilize urea in their diets;②strong caecum and coprophagy was the special physiological base for the utilization of urea;③microbiota was the key in use of non peotein nitrogen
出处
《江苏农业学报》
CSCD
北大核心
1999年第3期177-181,共5页
Jiangsu Journal of Agricultural Sciences
基金
国家自然科学基金
关键词
兔
禁食粪
日粮
尿素利用
同位素示踪
rabbit
prevention of coprophagy
utilization of urea in the diet
isotopic tracing