Influence of taurine on the growth performance and health status in laying hens

To evaluate the effects of taurine on the laying performance and health status in laying hens,4 000 green-shell laying hens, randomly assigned into control group,and treatments 1,2,3,respectively,were fed with the basal diet and the diet added 0. 01%,0. 1% and 1% taurine. The survival rate,laying rate,daily feed consumption and weight gain of each group were recorded every day. Seven weeks later,10 hens were selected randomly from each group and serum,livers and kidneys were aseptically collected. The results showed that taurine supplementation with different dosage in the diet improved the survival rate and laying rate of hens,among which 0. 1% taurine supplementation had the most significant effect on it. Histologic examination showed that taurine could ameliorate hepatic and renal structure. Compared with the control,the activity of serum alanine aminotransferase(ALT),and the levels of creatinine(SCr),blood uric acid(UA),malondialdehyde(MDA),low density lipoprotein cholesterol(LDL-C) of treatments 2 and 3 in serum were significantly lower,and the aspartate aminotransferase(AST) activity,serum triglyceride(TG) and total cholesterol(TC) content in treatment 2 also decreased significantly. Taurine could significantly enhance the high density lipoprotein cholesterol(HDL-C) content(P0.05). Tumor necrosis factor alpha(TNF-α),interleukin-1 beta(IL-1β) in kidneys and livers decreased with taurine supplied. Interleukin-4(IL-4) and interferon-γ(IFN-γ) significantly decreased with 0. 1% and 1% taurine supplimention. TNF-α,IL-1β,IL-10 levels of treatment 2,3 and IFN-γ,IL-4 levels of treatment 3 reduced significantly in livers. Total antioxidative capacity(T-AOC) activity of all three treatment groups increased in livers with taurine supplied(P0. 05). These results showed that dietary taurine could improve the survival rate and the laying rate of hens,enhance the antioxidant levels,facilitate lipid metabolism and decrease the level of inflammatory mediators. 0. 1% taurine supplied in the diet appears to be optimum for laying hens.