Gulevich R G, Klotchkov D V, Ivanova L N, Osadchuk L V
Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk.
J Reprod Fertil. 1995 Jan;103(1):147-52. doi: 10.1530/jrf.0.1030147.
Exposure of juvenile minks to artificial light conditions imitating early autumn (additional illumination from 20 June to 20 July followed by 8 h daylight from 21 July to 10 October--photoperiod I; 8 h daylight from 21 July to 10 October--photoperiod II) induced the prolonged modification of sex steroid concentrations. The increase in plasma testosterone concentrations during the prepubertal period was followed by a decrease before and during the mating period in experimental males. The concentration of oestradiol in plasma increased just before the start of the mating period (January and February) in females under photoperiod I, and these hormonal changes were accompanied by an increase in fertility. The conditions of photoperiod II (involving fewer hours of daylight) had less effect on the sex steroid concentration in the blood of females, and fertility was not changed. The response of gonads to hCG injection at the beginning of puberty (November) was higher in males exposed to photoperiod I conditions and in females exposed to both photoperiods than in control animals.
将幼年水貂置于模拟初秋的人工光照条件下（6月20日至7月20日额外光照，随后7月21日至10月10日为8小时日照——光周期I；7月21日至10月10日为8小时日照——光周期II），会导致性类固醇浓度的长期变化。实验雄性水貂在青春期前血浆睾酮浓度升高，随后在交配期之前和期间下降。在光周期I条件下，雌性水貂在交配期（1月和2月）开始前血浆雌二醇浓度升高，这些激素变化伴随着生育力的提高。光周期II的条件（日照时间较少）对雌性水貂血液中性类固醇浓度的影响较小，生育力没有变化。在青春期开始时（11月），暴露于光周期I条件下的雄性水貂和暴露于两种光周期下的雌性水貂对hCG注射的性腺反应高于对照动物。
