光照和埋植褪黑激素对绒山羊相关激素分泌的影响

Effects of Photoperiod and Melatonin on Some Hormones in Cashmere Goats

本试验旨在研究光照和褪黑激素对绒山羊内分泌的影响。本文采用随机区组试验的方法,把36只绒山羊平均分成3组,分别进行长光照(16L:8D)、自然光照(12.37hL)和短光照(8L:16D)处理,每种光照下一半埋植动物褪黑素,分别检测血液激素水平。结果表明:光照类型对绒山羊的激素分泌有显著的影响,长光照对催乳素(PRL)、类胰岛素促生长因子I(IGF-I)有促进作用,对褪黑素(MT)、胰岛素(INS)有抑制作用;短光照对催乳素(PRL)、IGF-I有抑制作用,对MT、INS有促进作用。埋植褪黑素后,在各种光照条件下对PRL、IGF-I均有抑制作用;INS在短光照+MT组降低,在自然光照+MT和长光照+MT组升高。这些都表明,几种激素在一天之内随着时间(光照)的变化而呈现不同程度的波动变化。

In order to investigate the effects of photoperiod and melatonin on the endocrine of some hormones. 36 castrated Inner Mongolia white cashmere mature goats, were selected and designed averagely to three groups randomly, which were exposed to long daily photoperiod （LDPP, 16L： 8D）, short daily photoperiod （SDPP, 8L： 16D） and natural daily photoperiod （NDPP, 12.37hL）, respectively. In each of the group, half of the goats were administrated by melatonin implanted monthly February to June based on the bodyweight. Results demonstrated there was a great variance in hormone content under different treatments, mean melatonin level was reduced with the prolonging of photoperiod, implanted groups were higher than unimplanted groups. Insulin level variation trend was similar to plasma melatonin, SDPP was higher than LDPP and NDPP, implanted groups were higher than non-implanted groups except for SDPP. On the other hand, PRL was increased with the prolonging of photoperiod, implanted groups were lower than non-implanted groups, fluctuation of PRL was also observed within a day following the variance of light, the highest peaks occurred at the time of the light terminate. IGF-I variation trend were similar to PRL but in SDPP and NDPP groups. In conclusion, photoperiod and exogenous melatonin manifested a remarkable effect on the hormone secretion of PRL,IGF-I and INS.