Superovulation and embryo recovery in two breeds of rabbits

Broiler rabbit does of two breeds, viz. New Zealand White (NSW, 6) and Soviet Chinchilla (SC, 6), were subjected to superovulatory treatment by administering PMSG (150 IU; intramuscular). At the induced oestrum, each doe was allowed to mate with two bucks and HCG (150 IU; intravenous) was administered. Equal numbers of control animals from the respective breeds were allowed double mating without any hormonal treatment. In the treatment group, high intensity oestrus was recorded in NZW and SC rabbits (66.7 and 83.3%, respectively), while the control animals exhibited moderate intensity oestrus. Both, NZW and SC rabbit does responded similarly to the superovulation treatment. Thus, the breed influence could not be appreciated in the ovulatory response. However, the ova recovery rate in NZW rabbits and percentage of fertilized embryos in SC rabbits were significantly affected in the treatment group. The dose of PMSG used might be higher and it would have caused disturbance in terms of recovery as well as the fertilization rate of the embryos. However, no breed influence could be noticed on the above parameters in control rabbits.