Developmental ability of precociously superovulated golden hamster eggs

Superovulated hamster eggs obtained by injections of PMSG on day 1 (the day of ovulation) and hCG on day 3 (2 days before expected day of next ovulation) have been used widely for assessing the fertilizing capacity of spermatozoa of the homologous as well as heterologous species. The developmental ability of these eggs was assessed by transferring them to host females (recipients) that had ovulated and mated naturally. The proportion of transplanted eggs developing into normal fetuses and young was the same regardless of whether the eggs had been collected from superovulated or naturally ovulating donors. The young originating from superovulated eggs were normal in that they grew at a normal rate and produced normal progeny. It may be concluded that the precociously superovulated eggs were as normal as the control (naturally ovulated) eggs. Thus, the use of precociously superovulated hamster eggs in evaluating the fertilizability of spermatozoa is justified.