Subcutaneous injection of corticosterone inhibits crop emptying rate in chicks.
Intraperitoneal injection of norepinephrine and epinephrine inhibits crop emptying rate in chicks.
The injection of alpha- but not beta-adrenergic receptor agonists also inhibits crop emptying.
These hormones did not affect the number of defecation.
These hormones inhibit food passage from upper but not lower digestive tract in chicks.