Effects of dietary supplementation of reduced glutathione on growth and IGF-1 level in serum and IGF-1 mRNA expression in tissues of broilers

One thousand 9-day old yellow feather female broilers were randomly allocated into 4 groups:A,B,C,D groups,with each group containing 5 replications of 50 chicks.The chicks were fed with basic diets supplemented with 0,80,120,160 mg/kg reduced glutathione(GSH) respectively for each group.The trial lasted 84 days.Effects of dietary supplementation of GSH on growth and IGF-1 level in serum and IGF-1 mRNA expression in tissues of broilers were studied.The results showed as follows:(1) The serum GSH levels of broilers in all supplemented GSH groups were significantly higher than that in control group(A group).(2) The mass and the average daily gain of broilers in all supplemented GSH groups were higher than that in A group,and it was significantly higher in B group than in A group.(3) Serum IGF-1 levels of broilers in all supplemented GSH groups were significantly higher than that in A group,Serum T3 levels of broilers in supplemented GSH groups were significantly enhanced and serum T4 levels had tendency to be increased.(4) IGF-1 mRNA expression in liver of broilers in all supplemented GSH groups increased,but not significantly and IGF-1 mRNA expression in muscle of C group was significantly higher than that of A group at 35 d.The results suggested that dietary GSH supplementation could stimulate the secret of IGF-1 in liver and the expression of IGF-1 mRNA in muscles,increase the serum IGF-1 level,and thereby promote the growth of broilers.