Efficient <i>in vitro</i> embryo production using <i>in vivo</i>-matured oocytes from superstimulated Japanese Black cows

Abstract

We examined whether the use of in vivo -matured oocytes, collected by ovum pick-up (OPU) from superstimulated Japanese Black cows, can improve the productivity and quality of in vitro produced embryos. The cows were superstimulated by treatment with progesterone, GnRH, FSH and prostaglandin F2α according to a standardized protocol. The resulting in vivo -matured oocytes were collected by OPU and used subsequently for the other experiments. The immature oocytes from cows in the non-stimulated group were collected by OPU and then subjected to maturation in vitro . We found that the rate of normally distributed cortical granules of the matured oocyte cytoplasm in the superstimulated group was significantly higher than that in the non-stimulated group. The normal cleavage rate (i.e., production of embryos with two equal blastomeres without fragmentation) and freezable blastocyst rate were significantly higher in the superstimulated group than in the non-stimulated group. Among the transferable blastocysts, the ratio of embryos from normal cleavage was also significantly higher in the superstimulated group than in the non-stimulated group. For in vivo -matured oocytes, it was observed that the pregnancy rates were significantly higher when normally cleaved embryos were used for transfer. Taken together, these results suggest that high-quality embryos with respect to developmental kinetics can be efficiently produced with the use of in vivo -matured oocytes collected by OPU from superstimulated Japanese Black cows.

Ovum Pick Up and in vitro Embryo Production using Sex Sorted Semen in Cows

“…In the present study small follicles were aspirated in greater numbers than medium and large follicles Similar to the results of Manik et al (2003), Goodhand et al (1999), Presicce et al (2020) Sakhong et al (2012), da Silva et al (2017 and Egashira et al (2019). This suggests that breed, season, environment, nutrition and stimulation protocols have an impact on follicular populations of various sizes.…”

Evolución de la aspiración folicular para producción in vitro de embriones en rumiantes

“…En un trabajo realizado en 2014, se lograron obtener 54.9% de blastocistos con semen sexado en ganado Holstein, a partir de ovocitos madurados in vivo (Figura 6) y sincronización de la oleada folicular mediante ablación del folículo dominante (Matoba et al, 2014). En 2019, al trabajar la PIV en ganado Black Japanese, se llegó a la conclusión de que se pueden generar embriones de mayor calidad y de manera eficiente cuando se utilizan ovocitos madurados in vivo colectados por OPU comparado con ovocitos inmaduros (Egashira et al, 2019).…”

Beneficial Effect of Polysaccharide Gel Made of Xanthan Gum and Locust Bean Gum on Bovine Oocytes

“…In vivo oocyte maturation occurs in follicular fluid, whereas in vitro, the condition for oocyte maturation is that of rigid plastic plates. In line with this difference, the quality of in vivo-matured bovine oocytes is better than that of in vitro-matured oocytes [ 1 , 2 , 3 ]. Follicular fluid contains proteoglycan and glycosaminoglycan at high concentrations, which have abundant hydroxyl bound with a negative charge.…”