Research advance in measurement of endogenous amino acid excretion at the terminal ileum using the isotope-labled endogenous nitrogen method;

Rice hull meal and corn stalk meal as the main sources of fiber, thirty 42-day geese as experimental animals and isotopic tracer technique as research method,were used to study for the first time the effect of diets containing different crude fiber levels(3%,5%,7%,9%,11%) with equal energy and protein on geese endogenous amino acid excretion and true digestibility of amino acid.

The results showed that NFD and REG could be used to estimate endogenous amino acid losses with the same accuracy (P>0.

Basal endogenous amino acid losses(EAAEb) in the 48h excreta of broiler chickens were directly determined by force-feeding nitrogen-free diet (NFD),NFD+3.

The excretion of endogenous amino acids is an important parameter in calculating protein true digestibility and in estimating protein and amino acids requirement.

This article reviewed the measuring techniques of endogenous amino acids,and the merits and demerits of every technique were discussed.

The total amount of endogenous amino acids determined by NFD was very significantly higher than that determined by FAS(P<0.

At water temperatures of 10℃,15℃,20℃,25℃and 30℃,we analysed the changing regulation of ammonia excretion and oxygen consumption rate,and discussed the proportion of protein which provide energy and endogenous nitrogen excretion(ENE)through analysing AQ(specific dynamic act.