In Vitro Development of Vitrified Rabbit's Embryos as Affected by some Nutritional and Hormonal Treatments

The purpose of the study was to measure the effect of 1-nutritional stages on reproductive performance in NZW rabbit doe. Total of 21 adult NZW rabbit were divided into 3groups (n=7). In the firstgroup does were given 100%NRC (Control,G1), In the second and third groups does were given 110(G2) or 120%(G3) from NRC for 3week before naturally mating. Weight, litter size and possibility rate at weaning and birth were recorded. 2-flushing (110% from NRC) (G1) and (superovulation, G2) using PMSG on ovarian activity, (recovery, freezability and in vitro development of rabbit embryos (n=4/group). Embryos were collected after 56h after naturally mating. Embryos freezing by vitrification and survival was assessed by in vitro culture. Results revealed that, 1-Total litter size and alive born at birth and litter size at weaning was much higher (P>0.05) in (Group2) than in other groups. 2-Mean number of corpus lutea and large follicles were much higher (P<0.05) in (Group2) than in (Group1) (8.5 and 6.25) also (6.25 and 4.5), respectively. Survival rate and normal embryos post-vitrification in (Group1) was higher than in (Group2) by 1.48% too 6.99% respectively. The percentage of hatched blastocyst stage in (Group1) was  significantly (P<0.05) higher than in (Group2) (83.33 vs. 71.74%, respectively). However, expanded blastocyst stage showed opposite of this trend. Conclusion, improving reproductive performance for rabbit does in G2 (110% from NRC) than in other groups. Also the potential in vitro growthing of rabbit embryos from flushing group post-vitrified was significant higher than in hormonal group.