Effect of a contraceptive compound (EP-1) on fertility of female Brandt's voles, gray hamsters and mid-day gerbils

摘要

We tested the effect of contraceptive compound of levonorgestrel and quinestrol (coded as EP-1) on the fertility of female Brandt’s voles, gray hamster and mid-day gerbils. Although less palatable (61% intake of control baits), reproduction of female Brandt’s voles in the laboratory was significantly prohibited by this contraceptive; the time of littering was delayed about 3 days longer and the proportion of littering females was reduced to 40-50%. Two-dose baiting was better than one-dose baiting in reducing fertility of voles. The proportions of littering females and the numbers of littering of gray hamsters and mid-day gerbils were also significantly reduced by this contraceptive within 3 months after animals were given two-dose baiting in laboratory. The effect of this contraceptive on gray hamsters was better than on mid-day gerbils. The contraceptive caused some mortality in mid-day gerbils. This contraceptive showed promise for fertility control of wild rodents. Two-dose baiting or one-dose satiation baiting are recommended for further tests in the field [ Acta Zoologica Sinica 50 (3): 341 - 347, 2004].