Growth Hormone Effects in Chickens

IN SOME mammalian species growth hormone (somatotrophin) is reported to increase body growth and protein retention as well as to induce hyperglycemia and glycogen deposition (Smith, Gaebler and Long, 1955). Thus far little work has been done to determine its effects in the fowl. Carter and co-workers 1953) injected 2-week-old chicks daily for 5 days with 1 mg. doses of growth hormone (containing traces of ACTH or TSH) and found no consistent effects. Hseih et al. (1952) obtained small increases in body weight and blood sugar of newly hatched chicks when 1 to 3 doses of 5 to 40 mg. of growth hormone were injected into eggs during the latter stages of incubation. Analysis of the latters’ data, however, indicates that the differences observed may not have been statistically significant. Failure of most of the eggs to hatch further complicated the picture. Since these published reports indicate that poultry differ …