The effect of prolactin on the hypophysis and testes of an Indian weaverbird (Ploceus philippinus)

Abstract

Injections of 2.5 or 5.0 mg of prolactin induced postnuptial-like regression of the testes of the male weaverbird (Ploceus philippinus) at the height of the breeding season but had no effect on regenerating feathers, which are of the cock type during the breeding season. These seemingly contradictory results can be understood on the assumption that prolactin suppresses the release of follicle-stimulating hormone but does not inhibit the output of luteinizing hormone. © 1964.