Co-culture of day-5 to day-7 equine embryos in medium with oviductal tissue.

The research is centered around studying the effects of oviductal tissue in the growth and morphologic development of equine embryos in vitro, and it indicates that incorporating oviductal tissue in the culture medium can potentially enhance embryo survival and development.

Introduction

This study involved observing the effects of oviductal tissue explants on equine embryos’ growth and development when cultured in vitro. Its focus was primarily on assessing the morphological developments of the embryos. The embryos were collected from mares between the 5th and 7th days post ovulation and then incubated for 5 days either in a medium alone (control group) or a medium supplemented with oviductal tissue explants (co-culture group).

Methodology and Results

• Embryos were evaluated and the media changed daily for both the control and co-culture groups.
• After being cultured for 5 days, all embryos that were found as morulae developed to the blastocyst stage.
• It was observed that 60% of the control embryos and 66% of the co-cultured embryos had reached the hatching blastocyst stage of development by the 5th day of being cultured.
• On the 3rd day of culture, more control embryos had degenerated compared to the co-cultured embryos. This difference became even larger by the 5th day of culture, indicating that the addition of oviductal tissue in the culture medium improved embryo viability.
• Moreover, the co-cultured embryos exhibited enhanced longevity compared to those grown in medium alone.

Hatching Process

In this study, the hatching process was characterized by two distinct phenomena. Either by the blastocyst squeezing through an opening in the zona pellucida or by the zona pellucida thinning across half of the blastocyst surface and subsequently disappearing entirely.

Conclusions

Overall, the study suggests that utilizing oviductal tissue explants in the culture medium of in vitro equine embryos may result in better embryo survival and morphologic development. The research indicates that the oviductal tissue can play a critical role in promoting the growth and development of equine embryos.