光照周期对叙利亚地鼠生长发育和繁殖的影响

对离乳雄性叙利亚地鼠（Ｍｅｓｏｃｒｉｃｅｔｕｓａｕｒａｔｕｓ）和雌性叙利亚地鼠各３０只分别给以长光照（１６Ｌ：８Ｄ）、中光照（１２Ｌ：１２Ｄ）和短光照（８Ｌ：１６Ｄ）三种光周期处理，研究光周期对叙利亚地鼠生长发育和繁殖的影响。１３周龄时，短光照处理组雄性地鼠的体重显著（Ｐ＜０．０５）高于长光照和中光照组的体重；雌性地鼠９周龄时长光照组的体重显著（Ｐ＜０．０１）高于另外两个处理组的体重，较高的日食量可能是长光照组具有较大体重的原因之一，雄性地鼠的睾丸、副睾和肾上腺重量及雌性地鼠的卵巢、子宫和肾上腺重量表现了随着光照时间的延长而递增的趋势。长光照条件有利于雌性地鼠的正常发情和繁殖。每天１６ｈ的光照对繁殖地鼠是比较适宜的。

Effects of Photoperiod on Growth, Developmentand Reproduction of Syrian Hamsters( Mesocricetus auratus )

he sffects of photoperiod on the growth, developinent and reproduc-tion of Syrian hamsters were examined in this experiment. There were23=6 groups of male and female weaning liamsters reared seperately inthree light: dark photoperiod circumstances ( 16L: 8D, 12L, 12D, and 8L: 16D) .At 13 weeks from birth, the body weights of shortlighting group( 8L: 16D ) male animals were significantly(P<0.05 ) higher than those ofthe other groups( i.e. 16L: SD and 12L: 12D ) . At 9 weeks from birth.the body weights of long-lighting group ( 16L: SD ) female animals weresignificantly ( P<0.01 ) higher than those of the other groups(i.e.12L,12D and 8L: 16D) . It is considered that the higlier daily intake mightbe one of the causes for long-ligliting female animals having greater bodyweights. With the increase of lighting time the weights of testes,epididy-mides and adrenals of male animals and the weights of ovaria, uteriand adrenals of female animals also presented a trend of incrsase. Long-lighting condition is beneficial to the normal estrogenicity and reproduc-tion of feinale hamsters. 16 hours lighting exposure each day is reasonablefor botli male and female breeding hamsters.