Polyovulatory response and in vivo embryo production at the romanian indigenous buffalo, out of breeding season in N-E of Romania

Abstract

In recent years, by using Buffaloes breeding biotechnology, it has been found to improve the results obtained in the recovery of embryos produced in vivo. Following limited research in buffalo, the viable embryo production has increased significantly from less than 1 per flushing to 2.5-3.0 in general and over 4 in isolated cases and conception rate following embryo transfer improved from about 10% to about 30-40%. However, the response to superovulatory treatment and recovery of viable embryos following superovulation is still low compared to cattle due to various factors (Tyagi S. 2007). Through this study we want to make contributions regarding the obtaining of invivo embryos and their rate of recovery by the method of washing the uterus at the Romanian Indigenous Buffalo, located outside the breeding season. The breeding season for Romanian Buffaloes in the major buffalo rearing countries appear to extend from September to March. A polyovulation protocol, described by Hafez (2007), with PMSG at the single dose of 2500 IU administered on day 13, one day before the removal of progesterone vaginal devices (PRID), was used. On the 12th day, a dose of PG was also given. Ovarian response showed a rapid evolution of ovaries, follicle count and size, and ovulation. The ovary volume increased by 3 cm on the day of the oestrus and by another 0.5 cm on the flusing day (from 2 / 1.5 cm to 5.5 / 4 cm the right ovary, and from 1.5 / 1 cm to 4/3 cm left ovary). Five follicles were grown on the right ovary and 3 on the left ovary with a diameter of 0.7-0.9 cm. Of which ovulated only 6. Four corpus luteum were diagnosed on the right ovary and 2 on the left. After washing the uterus 6 days after insemination, a number of 4 embryos were recovered and identified in the laboratory. Three embryos came from the right horn and only one left.Depending on the embryonic stage of development and segmentation, two embryos were in the blastocyst stage and two were in the stage of compact morgue with non-homogeneous chromatin. Qualitative assessment of embryos was classified as two high quality transferable embryos and two non-transferable embryos