Stimulation of food intake and growth of chickens by cyproheptadine: lack of interaction with the effects of pinealectomy and melatonin.

Cyproheptadine stimulates food intake and growth in some species of mammal; its effects are reported here in chickens. Growing cockerels of an egg-laying strain were given 0.32 mg/d by mouth, which resulted in significant increases in weight gain and food intake, including feeding during the night. Increasing daily doses of up to 1.6 mg/kg body weight stimulated intake in a dose-related manner, while 1.92 mg/kg had the same effect as 0.96 mg/kg. Neither pinealectomy, which is known to stimulate food intake, nor treatment with melatonin, which depresses intake, interacted with the effects of cyproheptadine on food intake, showing that its effect is not mediated by the pineal gland.