一种复方避孕药物对围栏内大仓鼠种群繁殖力的影响

本文报道了由左炔诺孕酮和炔雌醚配伍制成的复方避孕药物（代号：EP-1）对围栏内大仓鼠种群繁殖力的影响。实验分为4个组：对照组、0．001％毒饵组、0．003％毒饵组和0．003％毒饵预处理组，并各设有一组重复。于2001年6月，在每组围栏内各放入5雄5雌成年大仓鼠，检验投放EP-1毒饵后对大仓鼠繁殖力的影响。至9月份，2个对照组新出生鼠数量均为12只，平均每雌繁殖力为2．4；而所有6个EP-1处理组新出生鼠数量均为4只或以下，平均每雌繁殖力在0．4～0．8之间。结果表明，处理组大仓鼠的繁殖力明显受到了，不育剂EP-1的抑制。在半自然状况下，投放足量的EP-1毒饵可以有效降低大仓鼠种群的繁殖力和数量。

Effect of a Contraceptive Compound on Reproduction of Greater Long-tailed Hamsters (Tscherskia triton) in Experimental Enclosures

We tested the effects of a contraceptive compound of levonorgestrel and quinestrol (coded as EP-1) on reproduction of greater long-tailed hamsters in eight experimental enclosures.The test subjects were divided into four groups with two replicates for each group: control group (0% EP-1), 0.001% EP-1 group, 0.003% EP-1 group, and 0.003% EP-1 group with pre-baiting before test. In June of 2001, each enclosure was supplied with 5 male and 5 female adult greater long-tailed hamsters, and with baits. In September, twelve newborn hamsters were captured in both control enclosures.Thus, each female produced an average 2.4 newborn hamsters. Less than four newborn hamsters were captured in each of the six EP-1 treatment enclosures, thus,each female produced an average of 0.4-0.8 newborn hamsters. The results indicated that the reproduction of hamsters in enclosures with treatment of EP-1 baits was obviously inhibited. Thus we suggest that in natural conditions, EP-1 would be promising in controlling reproduction of hamsters if they are supplied with enough baits.