INFLUENCE OF B-CAROTENE ON FERTILITY IN RABBITS WHEN USING EMBRYO TRANSFER PROGRAMS

The effect of beta-carotene on reproduction traits in rabbits was stud ied in 509 (superovulated and normally ovulated) donors and 239 recipi ents by using embryo/gene transfer performed at 2 different locations. All of the bucks and the half of the females were fed a diet suppleme nted with 40 mg synthetic beta-carotene (Rovimix(R))/kg feed. Embryos at the pronucleus stage were collected 19 to 21 hours after induction of ovulation with human chorionic gonadotropin (hCG); they were then m icroinjected into the male pronucleus and transferred to synchronized recipients. Data were obtained from the time when the donors and recip ients were caged, until the pups resulting from the embryo transfers w ere weaned. Supplemented beta-carotene did not affect most of the 30 t raits that were analyzed. However superovulated donors in Project 2 th at received the beta-carotene enriched diet had a 14% lighter ovary we ight (P<0.05) and less than half of the oocytes were unfertilized (P<0 .05). In Project 1 (beta-carotene group) there was a greater number of pups born (36%, P<0.05) and more of these pups were born alive (53%, P<0.05).