Vitrification of equine embryos.

This research article reports how vitrification, a rapid freezing process, can be successfully used to cryopreserve horse embryos. It provides guidance on different stages of the process – from collecting embryos from donor mares to actually conducting vitrification and subsequent transfer into the recipient’s uterus.

Understanding Vitrification

• Vitrification is a rapid freezing process used for the preservation of biological material. In this research, it is specifically used for the cryopreservation of equine embryos.
• The method is shown to be effective especially when using small embryos and offers a quick way to cryopreserve horse embryos.

Collection of Embryos for Vitrification

• For vitrification to be successful, the study details that embryos should be collected from donor mares when they are, or less than, 300mm in diameter.
• The embryos need to be at the morula or early blastocyst stage of development—critically, this refers to specific stages in the growth of an embryo after fertilization.

Vitrification Process

• No special equipment is necessary for vitrification. The straw containing the embryo is exposed to vapor for a minute before being plunged into liquid nitrogen.
• Liquid nitrogen, serving as a cooling agent, is often used in cryopreservation processes to quickly ‘freeze’ and thus preserve the biological material without causing damage.

Post-Vitrification Transfer

• Warming of the straw also doesn’t require special tools, making the method accessible.
• Once thawed, the embryo can be directly transferred from the straw into a recipient’s uterus.
• This ability to transfer the embryo directly into the uterus is of high importance. It ensures minimal handling of the embryo, potentially increasing the likelihood of successful pregnancy.