Effects of Nitrogen-Free Diet Method and Fasting Method on Endogenous Amino Acid Losses of Yangzhou Geese

Endogenous amino acid losses in intact and caecectomized geese were determined by nitrogen-free diet method(NFD) and fasting method(FAS) in this study and the differences of the two methods were compared.Twelve adult male Yangzhou geese were randomly divided into two groups with six birds in each group,and one group was chosen to be caecetomized.The geese were fasted for 24 h and the endogenous amino acid losses were detected by collecting all excrement in 24 h.The results showed that endogenous serine,leucine,and phenylalanine losses in caecectomized group determined by NFD were significantly lower than those in intact group(P0.05),endogenous arginie loss in caecectomized group was extremely significantly higher than that in intact group(P0.01),and the other endogenous amino acid losses determined by NFD were similar(P0.05).The endogenous aspartate and valine losses in intact group determined by FAS were significantly higher than those in caecectomized group(P0.05),and the other endogenous amino acid losses determined by FAS were similar(P0.05).It is concluded that endogenous amino acid losses in intact and caecectomized geese determined by NFD and FAS are different,most of endogenous amino acid losses are extremely significantly different,and all most endogenous amino acid losses determined by NDF are higher than those determined by FAS