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Embryo Transplants

As an undergraduate student it is very easy to get frustrated when studying the basics. Organic Chemistry, Nutrition, or Statistics feel like classes you just have to get through before you can study bigger and better things. Plus you can get so bogged down in details that you tend to lose sight of the big picture and what you are working towards. So when I was given the opportunity as part of my Animal Science 107 Honors course to help with embryo transplants in sheep I jumped at it!

So first, let me give you a little background about embryo transplants in sheep. The goal of this procedure is to create more lambs from the genetically valuable females. Naturally a female sheep, called a ewe, might have 14 lambs in her lifetime if she is lucky. So as producers we want to greatly increase the number of lambs from a given female. In order to do that we give the valuable, donor ewe hormones that cause her to 'super-ovulate' increasing the number of viable eggs she produces. This then increases the number of embryos, or fertilized eggs, she potentially can create. They then take the valuable female sheep and breed her to a prize ram to hopefully create a 'super' lamb. The donor's embryos are flushed from the oviducts via an abdominal surgery and transplanted into the oviducts of a recipient ewe that has been 'programmed' through hormones to be in the same stage of the estrus cycle. This recipient ewe, who was selected for her maternal characteristics, will then give birth to the lambs and raise them as if they were her own. And there you go - we have maximized the number of offspring from our most genetically valuable animal, improving the breed and overall performance.

As we went through the day and talked about all that goes into the embryo transplants, I found myself making connections to basics. We talked about the different supplements and dietary needs of sheep before, during, and after pregnancy. We discussed the odds of having the embryos implant in the recipient ewes and a successful pregnancy. We also learned about the chemistry of some of the hormones that were manipulated in order to synchronize the estrus cycles of the ewes. It was really satisfying to have all of that knowledge come together! Plus it gave me some much needed encouragement as we slowly make our way towards the end of the semester. The challenge of getting in to Vet School can seem overwhelming at times but if you just keep reminding yourself why you love veterinary medicine it makes everything a little bit better.