| Abstract: | Contents: From 7 White Vienna male rabbits semen was collected and stored for 0, 2, 4, 6 and 8 days. One-hundred-forty White Vienna does were inseminated with semen stored at 5° C to test the effects on fertilization rate, embryonic mortality and conception rate. Seven does were removed from the experiment at 48 hr. (embryo stage), 6 days (blastocyst stage), 16 days (fetal stage), and the remaining 7 does were allowed to complete the gestation. This was complete for each semen storage time. Results: - 1 Conception rate: The embryo stage had 100 percent conception using semen stored for 0 to 6 days. Eight days in storage showed a lower conception rate. The late developmental stages had a lower conception rate resulting from increased embryonic mortality.
- 2 Fertilizability Semen stored for 4 days or longer had a significantly (P < 0,05) reduced ability to fertilize the ova.
- 3 Prenatal mortality, The prenatal mortality was ?55, ?41, ?27, +6, ?18 percent for sperm storage times of 0, 2, 4, 6 and 8 days resp. The mortality up to implantation (6 th day) decreased until to the 4 th day and increased thereafter. The post-implantation mortality increased on the 2nd day of storage and decreased afterwards, with the lowest percentage after 6 days of in vitro storage of sperm at 5° C. The total wastage (fertilization losses and prenatal mortality) was ?58, ?51, ?66, ?54, ?94 percent for 0, 2, 4, 6 and 8 days of sperm storage resp.
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