Regulation of the Breeding Season in Mammals
نویسنده
چکیده
The nature of seasonal breeding in both domestic and wild mammals has been known for centuries but only recently have we gained some insight into the mechanisms involved. Environment, encompassing climatic, nutritional, and biotic factors, plays a major role in synchronizing reproductive rhythms. Examples of the effect of environmental factors upon reproductive activity are discussed within the conceptual framework of central nervous control of pituitary secretion.
منابع مشابه
“Short Paper” The Effect of Short Term and Long Term Feeding of Barley Seed with or Without eCG on Reproductive Performance of Goat During Breeding and Out Breeding Seasons
Nutritional and hormonal programs are one of the important ways of improving goat reproductive performance. Therefore, the present study was conducted to investigate the effect of using barley seed and eCG at the same time on the reproductive performance of goat in nomadic breeding conditions. The number of 60 goats of two to three-year-old in the breeding season and 60 goats of three to four-y...
متن کاملNew Technique for Activating Reproductive System during Non-Breeding Season in Ghezel Ewes
Ghezel sheep is one of the main breeds in the north-west of Iran which is reared for meat, milk and wool production. Improving reproduction of this breed will have a significant impact on the economic development of local farmers. Therefore, in the present study the effect of simultaneous use of estrus synchronization(controlled internal drug releasing (CIDR) and equine chorionic gonadotropin (...
متن کاملCalling underwater is a costly signal: size-related differences in the call rates of Antarctic leopard seals
It is proposed that where sexually selected vocal communication is an honest signal, the call production rate is predicted to change throughout the breeding season. Male leopard seals call underwater for many hours each day over their three- to four-month breeding season, and it is hypothesized that a decrease in calling rate would be associated with the declining body condition of smaller male...
متن کاملBehavioural and hormonal effects of social isolation and neophobia in a gregarious bird species, the European starling (Sturnus vulgaris).
Separating gregarious individuals from their group members often results in behavioural and physiological changes, like increased levels of corticosterone. Testosterone and corticosterone, in particular, have been implicated in the response of mammals to novelty. Data in birds are, however, rare. The presence or absence of group members may also influence an individual's response to novel stimu...
متن کاملConcentrations of insulin-like growth factor-I in adult ž / male white-tailed deer Odocoileus irginianus : associations with serum testosterone, morphometrics and age during and after the breeding season
Ž . Our understanding of insulin-like growth factor-I IGF-I in cervids has been limited mostly to its effects on antler Ž . Ž . Ž . Ž development in red deer Cer us elaphus , roe deer Capreolus capreolus , fallow deer Dama dama , and pudu Pudu . puda . Although IGF-I has been found to play a critical role in reproductive function of other mammals, its role in reproduction of deer is unknown. Th...
متن کامل