Improving Bovine Embryo Development and Quality Using Bovine Oviductal Epithelial Cell-Derived Conditioned Medium (bOEC-CM).

BACKGROUND

The embryo co-culture systems with the monolayer cultured cells are complex, unreproducible, and have a high probability of biological contamination. Therefore, nowadays, using conditioned media is a suitable alternative to these methods.

OBJECTIVES

This study aimed to investigate the impact of utilizing bovine oviductal epithelial cell-derived conditioned medium (bOEC-CM) on subsequent embryo development and quality.

METHODS

Bovine embryos produced in vitro were cultured in a specific medium supplemented with either 5% charcoal-stripped FBS (Charcoled Strip Serum [CSS]) or 10% bOEC-CM from either Days 1 or 3 post-fertilization. Various parameters, such as cleavage rate, blastocyst formation, hatching rate and blastocyst quality, were assessed.

RESULTS

The results indicated that adding 10% CM from Day 1 significantly reduced the cleavage rate compared to using CSS on the same day (p < 0.05). Furthermore, the CSS and CM from both Days 1 and 3 increased blastocyst formation rates (p < 0.05). Notably, the addition of 10% CM on Day 3 significantly improved the hatching rate compared to the other groups (p < 0.05). Both CM and CSS were found to enhance the inner cell mass (ICM), trophectoderm (TE) and total cell numbers in blastocysts when used on both Days 1 and 3 (p < 0.05). Additionally, CM from Day 3 positively influenced the expression levels of development-specific genes in cultured embryos (p < 0.05).

CONCLUSION

Overall, the findings suggest that using bOEC-CM at a 10% concentration may provide a promising supplement even better than serum and traditional co-culture methods during the last 5 days of embryo culture.