Establishment of equine oviduct cell monolayers for co-culture with early equine embryos.

The research documents the process of creating a culture for equine oviduct epithelial cells, which then brings about new understanding of the in vitro development of equine embryos both with and without cellular support.

Creation of Equine Oviduct Cell Monolayers

• The researchers managed to cultivate a culture for equine oviduct epithelial cells.
• The primary cultures achieved cell saturation between 5 to 8 days, creating a monolayer of polygonal cells that held their morphology for up to 20 days.
• Further round of cell culture was established by using cells that got detached themselves from the monolayers, once again achieving cell saturation in 5-7 days.
• Cells that were frozen before primary culture reached cell saturation between 10 to 15 days after defrosting.
• Even dishes that held saturated cells and were frozen created some cohesive monolayers after being thawed.

Co-Culturing Equine Embryos

• The researchers co-cultured equine embryos that were collected 2 days post ovulation with the monolayer of equine oviduct epithelial cells created earlier and some were cultured alone.
• In the group cultured alone, 3 out of 5 embryos contained 12-20 cells, 1 reached the morula stage and 1 got to the blastocyst stage after 4 days of culturing.
• In the group co-cultured with oviduct cells, 2 out of 5 embryos contained 12-16 cells, 1 got to the morula stage and 2 reached the blastocyst stage after 4 days of co-culturing.
• After 2 extra days, the blastocysts showed only delayed development, without a capsule and very little size increase.

Conclusion of the Study

• The research showed that equine embryos can develop in vitro from 4 to 8 cells to the blastocyst stage in co-culture with equine oviductal monolayers as well as without external cellular support.
• However, the research also mentioned that the number of embryos studied to conclude the benefits of co-culturing was too limited.