Testicular changes of acute vitamin A deficiency of cockerels.

Sixty, 1-day-old Arbor Acres broiler cockerels, randomly allotted to three groups, were fed a vitamin A-deficient diet, vitamin A complete diet (control diet), or control diet pair-fed in an amount equal to the quantity consumed by the vitamin A-deficient group. Secondary sex characteristics, as indicated by comb enlargement, developed more rapidly in cockerels consuming the deficient diet. A difference in direct testicular weight was not observed between vitamin A-deficient birds and pair-fed controls, but the testicular weight relative to body weight and the level of testicular maturity were greater in the former. Ultrastructurally, lipid droplets were found in Sertoli cells and germinal epithelium of the deficient birds, but not the pair-fed controls. Paradoxically, serum testosterone concentrations were significantly reduced in sequential serum samples from vitamin A-deficient chicks, but not controls. The evidence indicated that vitamin A deficiency has an androgenic effect in cockerels despite reduced testosterone concentrations.