Purified chicken growth hormone (GH) and a human pancreatic GH-releasing hormone increase body weight gain in chickens.
Purified chicken GH (cGH) and a synthetic human GH-releasing hormone (hpGRF) were tested for the ability to improve growth performance in chickens. Purified cGH was given to 4-week-old cockerels at 5, 10, and 50 micrograms/day for 14 days via daily iv injection. Body weights of chickens receiving 5 and 10 micrograms/day cGH were significantly increased at 6 days by 13.5% and 11.2%, respectively, relative to control values. At 14 days, body weights averaged 8.1% and 7.7% greater than controls, but these values were not statistically significant. There was a slight stimulation of body weight gain in chickens receiving 50 micrograms/day cGH. In general, cGH produces a transient stimulation of body weight gain in chickens. hpGRF was also given to 4-week-old cockerels for 14 days via daily iv injection at 0.1, 1.0, and 10.0 micrograms/day. hpGRF at 0.1 microgram/bird daily increased body weight on day 14 (9.1% over the control value). The stimulating effects of hpGRF on body weight are also transient. The effects of cGH on serum somatomedin-C (SM-C) were examined. Serum SM-C concentrations were significantly elevated 24 and 36 h after injection of cGH. In conclusion, purified cGH and hpGRF appear to have some growth-promoting activity. The stimulatory effect of hpGRF on weight gain may be mediated via GH, and the stimulatory effect of cGH could be mediated through SM-C.
D000818:Animals; D001835:Body Weight / Q000187:drug effects; D002645:Chickens / Q000254:growth & development*; D013006:Growth Hormone / Q000378:metabolism / Q000494:pharmacology*; D013007:Growth Hormone-Releasing Hormone / Q000494:pharmacology*; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000097:blood; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008297:Male; D010179:Pancreas / Q000032:analysis
D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone; D013007:Growth Hormone-Releasing Hormone