Effects Of Glucocorticoids On The Growth And Metabolism Of Broiler Chickens

Five trials were conducted to investigate the effects of glucocorticoids on the growth and metabolism of broiler chickens. We used exogenous glucocorticoids to induce stress and studied the effects of stress on performance, tissues development, protein metabolism and meat quality in broiler chickens.In trial 1 of chapter 1, broiler chickens were fed with corticosterone (30 mg /kg diet) for 4 days to induce stress, in order to investigate the stress effects of neonatal chickens. 180 male broiler chickens of 3d used in this trial were divided into 2 guoups at random, as control group and stress group, each group included 3 replicates with 30 broiler chickens each. Stress group were fed corticosterone (30 mg /kg diet) since 3d of age. At the day of 7, birds were weighed, samples were obtained from 4 birds randomly selected from each replicate (12 birds each group) for determination. The results indicated that the performance of birds suffered from stress were significantly lower. The concentration of plasma glucose (GLU), uric acid (UA) and total free amino acid (TFAA) were significantly higher, The liver weights (%) were significantly higher and the abdominal fat were lower.Trial 2 investigated the effects of stress experience on performance and development of muscle tissus. 120 male broiler chickens of 3d used in this trial were divided into 2 guoups at random, as control group and stress experience group, each group included 3 replicates with 20 broiler chickens...