Gonadal function in most animal species exhibits considerable annual fluctuations, with
gametogenesis and fertility often being confined to a short and rigidly controlled breeding
season. In males, production of androgenic steroids by the testis is usually maximal
immediately before and during the breeding season. In the golden hamster, seasonal
regression of the testes is associated with decrease in the total content of luteinizing
hormone (LH), follicle-stimulating hormone (FSH) and prolactin (PRL) receptors, and similar …