Ovulation, ovum transport and implantation in the adult golden hamster.

The time of ovulation in various hamster colonies and its relationship with the period of light as reported in the literature was compared with the observations made in this study. Ovulation and transport of ova to the oviduct was studied during days 4 and 1 of the estrous cycle. Microscopical examination of the various oviducal segments for the presence of ova resulted in a detailed description of physiological ovum transport for the adult golden hamster. Simultaneously the developmental stages of ova were checked together with the occurrence of unfertilized ova and the percentage of ova implanted in the uterus. Finally, the contractility of the oviduct in vitro was observed for groups of animals at different times in the pre- and postovulatory period. The presented data indicate that the golden hamster is useful for the study of ovum transport processes. This is due to the regularity of its estrous cycle including multiple ovulations, and because ovum transport can easily be monitored microscopically with a high degree of reliability.