Abstract
The effects of body weight and population density on the number of ova shed were examined in the superovulation-treated adult rat in order to clarify the variation of the number of ova shed. Twelve-week-old female rats, weighing 182-277 g, were injected with 40 i. u. of PMSG on metestrus, with sodium pentobarbital on diestrus (“critical period”), and with 40 i. u, of hCG, on estrus. Twenty hours after the injection, the number of ova shed in an ampulla was observeld. There was no correlation between body weight and the number of ova shed (r=0.004) . The rats were kept in at three, six or nine rats per cage (260×380×180mm) from weaning at 30 days old to 12 weeks, with superovulation treatment. There was no significant difference in the number of ova shed among the various population densities.