Akademik Veri Yönetim Sistemi
8. Ulusal 4. Uluslararası Sürü Sağlığı ve Yönetimi Kongresi, Antalya, Türkiye, 7 - 10 Kasım 2024, ss.308-309, (Özet Bildiri)
This study aims to share the pregnancy rates obtained after embryo development and transfer from the In Vitro Fertilization and Embryo Transfer (IVF-ET) laboratory established in a dairy farm. Healthy Simmental and crossbred cows (n=20) aged 18-84 months were included in the study. Cows were subjected to OPU twice or once a week between January and May 2024. The OPU procedure was performed under transvaginal ultrasonography guidance and all follicles above 2-3 mm on the ovary
were aspirated. The aspiration fluid was filtered in the IVF laboratory and oocytes were classified according to their quality under a microscope. Oocytes were transferred to a maturation medium and
matured in a 5% CO2 incubator for 21 hours. Conventional and sex-sorted semen were used for
fertilization of the expanded oocytes. After 24 hours, the oocytes were cleared of cumulus cells and transferred to a culture medium. The number of developing embryos was recorded on the 7th day after fertilization.
During the study, 1126 oocytes were aspirated after 145 OPU procedures and an average of 7.8 oocytes (1126/145) were obtained per cow. Oocyte division rate was 58.9% (663/1126) and embryo
development rate was 35.6% (236/663). There was no difference in oocyte division rates after OPU once
and twice a week (64.3% and 58.0%), while the embryo development rate was lower (P<0.05) in those
who underwent OPU twice a week (44.4% and 33.1%). There was no difference (60.5% and 61.5%) between conventional and female semen in terms of cleavage rates, but the number of developing embryos was higher in conventional semen (42.2%; 182/431) than in female semen (23.7%; 54/228) (P<0.05). Of the embryos, 56 fresh and 34 frozen embryos were transferred to surrogate cows.
Pregnancy rates were 28.6% (16/56) in fresh embryos and 21.0% (7/34) in frozen embryos, and 25.6% (23/90) pregnancies were obtained in total.
As a result, it was determined that embryos could be produced from oocytes obtained from cows with high breeding value by OPU method and promising pregnancy rates were obtained after the transfer of these embryos. The use of OPU and IVF applications under field conditions will contribute significantly to animal breeding by providing rapid and effective production of genetically superior
individuals.