The effects of trienbolone acetate on carcass composition, conformation and skeletal growth of turkeys.

1. The carcasses of 66- and 73-d-old stag turkeys implanted with 20 mg trienbolone acetate (TA) at 49 d of age were analysed and the results compared with those of untreated controls. 2. Treatment with TA improved growth, increased carcass moisture and tended to decrease carcass fat and ash; protein content was not altered by implantation. 3. Treatment with TA produced a marked improvement in efficiency of conversion of dietary protein to carcass protein. 4. Carcass formation of 70- and 77-d-old turkeys of both sexes implanted with 20 mg TA at 49 d of age was not markedly different from that of controls in terms of the relative proportions of the major body components nor in relative skeletal proportions. 5. Implantation with TA reduced linear and appositional skeletal growth both relative to soft tissue growth and relative to skeletal growth of control turkeys. 6. The rate of bone remodelling was reduced more than the rate of appositional growth so that bone cortical thickness was increased. 7. The changes in the skeleton effected by TA are consistent with the hypothesis that the drug acts by decreasing the rate of protein turnover, with catabolism being depressed more than anabolism.