Effect of sperm count on the fertility and prolificity rates of meat rabbits

The effect of sperm count per insemination dose was evaluated on fertility and litter size at birth. In the first experiment, 124 receptive multiparous does were inseminated with 16, 4, 2 and 1 million spermatozoa. Does were slaughtered 12 days after insemination and the number of implanted embryos were recorded. Does inseminated with 16 or 4 million sperm showed no differences in pregnancy rate (90%) and number of implanted embryos (10.7). Does inseminated with 2 million sperm had a lower pregnancy rate (66%, P < 0.05) and does inseminated with 1 million sperm had lower fertility (23%, P < 0.05) and number of implanted embryos (4.9, P < 0.05). In the second experiment, 395 receptive does in different reproductive status were inseminated with 16 or 4 million spermatozoa. No differences were found in fertility (74%) and litter size at birth (9.0). No interactions between sperm count and reproductive status were observed.