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.