Temporal secretory patterns of growth hormone in young meat‐type poultry

Abstract
1. Temporal secretory patterns of plasma growth hormone were measured in young, male meat‐type poultry at three stages (22, 30 and 44 d of age) during normal growth. 2. Birds were cannulated in the jugular vein and, after a 2‐d period of recovery were serially bled every 10 min for 3.5, 5.5 and 10 h for birds 22, 30 and 44 d of age respectively. 3. GH secretion was found to be pulsatile and episodic, with a mean (±SE) peak frequency (number/h) of 0.85 (±0.03) over all ages (n=15). Birds at 22 d of age had significantly greater peak magnitudes, baseline concentrations and overall mean concentrations than those at 30 and 44 d of age.