Seasonal reproduction in the male Reproducción estacional en el macho

Abstract

There is a surprising interrelationship between environments and adaptation of reproductive behavior, very evident in seasonal breeders; which may reproduce in long or short days, according to proximal factors, mainly the light photoperiod which triggers photoneuroendocrine changes. These involve photoreceptors, a clock and the neuroendocrine apparatus. Gonadotropins (GT), gonadal development, negative feed back of GT done by sexual steroid, the intervention of the retino-hypothalamic fibers, and suprachiasmatics nucleus as well as melatonine secretion, intervene in this regulation. Of importance is the pulse generator of the hypothalamus (medial eminence) and its control of adenohypofisis for the secretion of LH and FSH. In the testis interstitial endocrine cells (Leydig)(secreting testosterone and also estrogens), establish a feed back loop with the adenohypofisis and hypothalamus in a circuit of long, short and ultra short circuit with neuroendocrine neurons playing a key role. Sust