Preliminary Post

During the next seven weeks or so, this Blog will be updated frequently and will focus on the subject of and concerning equine reproduction. There are a whole lot of directions that my research could go in but I think as of now I will focus on embryo transfer and the various steps it takes to successfully obtain an embryo (not an oocyte) from one mare and transfer it to another. Supposing this is the main vein of my blog, one article I may come back to is from the Feb2006 issue of "DVM: The Newsmagazine of Veterinary Medicine" and it is written by Ed Kane. The abstract says that the article reviews various agents that will cause a mare to come into estrus and some that will ovulate. The principle of induced ovulation as it is related to embryo transfer is that the donor mare and the recipient mare must have ovulated within a specific number of days so it may be necessary to cause one or both of the mares to ovulate.

Another article not directly related to embryo transfer but on the topic of hormonal regulation in pregnant mares is authored by J.C. Ousey and is in the August 2004 addition of Reproduction in domestic animals. The best bridge between embryo transfer and the entire cycle of hormonal regulation of a mare before and during parturition would be to look at specifically what could cause an acceptable donor mare to abort the fetus after a substantial period of time, and are these the same things that cause a normal mare carrying her own fetus to abort? A phenomenon that I saw twice during my stay at an equine reproduction facility in Ocala, FL was a blighted ovum, or an embryo that was alive when transplanted but for some reason never developed once in the recipient mare. I have not found any research on this yet, but it sounds like something fascinating to look into. One last study I found which also is intriguing studied what happened when both fresh and thawed frozen semen were injected via a drill cytoplasmicly into oocytes which were then developed in a lab as well as in a live horse (in vitro and in vivo, respectively). The study is published in “The Journal of the Society for Reproduction and Fertility” in 2002. It would be interesting, since this is four years old to see how the outcomes and observations compared to more recent successes in live embryo transfer today and if the practice of implanting semen in this manner is still an accepted and useful practice.