Effects of different levels of valine amino acid on performance, carcas traits, meat quality and insulin like growth factor-1 and insulin genes expression in male Ross 308 broiler chickens

The aim of this experimentwas to investiagatethe effects of different levels of valine on performance, carcass traits and quality and insulin like growth factor-1(IGF-1) and insulin genes expression in male Ross 308 broiler ckickens. Present study performed using 250 one day male broiler chicks Ross 308 in completiy randomized design including 25 pen, 5 treatments and 5 replicates each (10 chicks in each replicate) with 5 levels of valine (100, 105, 110, 115, 120 percent of Ross starin requirments). At day 42 of age, one chick from each replicate slaughtered to determine the carcass traits, meat quality, serum IGF-1 and insulin and IGF-1 genes expressions. The improved body weight gain and decreased feed conversion ratio during starter, grower and finisher periods were observed by consumption of 110% valine level. Consumption of 110% valine caused the increased carcass, breast and thigh and lowered abdominal fat at 42 days of age. The IGF-1 and insulin genes expression of breast muscle and liver increased by 115% valine. At day 42 of age, consumption of 110% valine improved the protein, dry matter, crude fat and ash content of meat. In conclusion, consumption of 10% higher than Ross valine requirements increases the IGF-I and Insuline genes expressions through up-reguletion of mTOR and promotion of S6k1 phosphorylation signaling mRNA translettion and protein synthesis and hence improves the performance and carcass quality and decreases the abdominal fat in Ross 308 broiler chickens.