Effects of vitamin A deficiency on the pituitary‐gonad axis of the California quail, Lophortyx californicus

Vitamin A deficiency results in a decrease in number of large basophils (presumed gonadotropes) in male Lophortyx californicus and a decrease in large basophil cell diameters in females. Decrease in functional activity (as judged by number and size) of this cell type may be partially responsible for the observed effects of vitamin A deficiency on reproduction. Gonads of nondeficient birds respond positively to gonadotropins. The testes of vitamin Adeficient birds produce androgens, but spermatogenesis was subnormal. The hormone‐producing component of ovaries of vitamin A‐deficient birds responds to gonadotropins, but follicular development does not occur. Vitamin A deficiency in the California Quail appears to act both at the pituitary (and/or hypothalamic) level and at the gonadal level to result in decreased reproductive competence.