Agriculture Education – example of a prepared speech assignment.
Today I would like to visit with you about Cindy Pennington. Cindy was one of the first animal scientists who worked on developing modern genetics in dairy cattle through the use of super ovulation and embryo collection and transfer.
Ms. Pennington grew up in a small rural dairy farming community in Wisconsin. One of her loves was choring the calves. Due to her inquisitive nature, she began working on getting a quality dairy cow to have more than 1 calf per year.
While a veterinary medical student at the University of Wisconsin, Ms. Pennington began to research the topic of super ovulation and then how to collect the embryo’s and transplant them into other dairy cows. She was one of the very first veterinarians to specialize in the modern practice of embryo collection and transfer that involved dairy cattle in North America.
Her process of super ovulation was to inject the dairy cow with a hormone that would cause the ovaries to release many more eggs than normal. A typical dairy cow releases 2 to 4 eggs from the ovary every 21 days. With the use of hormones, that same dairy cow is now releasing 30 to 40 eggs. A few days after injecting the hormone, the cow would be bred either by a high quality bull or through the use of artificial insemination. One week later, Ms. Pennington would enter the cow’s reproductive tract with a special device that would ‘flush’ all of the fertilized eggs out of the dairy cows reproductive tract and collect all of the developing embryos. After the flushing process was over, she would examine the embryo’s under a microscope to analyze them and decide which could be used. Sometimes there would be as many as 23 healthy, fertilized eggs.
These developing embryo’s will then be transferred or implanted into donor cows – these are cows that would serve to be the mothers because of their ability to care for the calf by carrying the developing embryo through pregnancy and then give birth to them and continue to care for them with her milk production.
Due to her initial research, the practice of embryo collection and transfer become a standard practice in many dairy herds throughout the world as farmers attempt to produce more milk for human consumption.
In more recent time, Dr. Pennington has worked with a group of other veterinarians and researchers to genetically modify the dairy cows to produce milk with more vitamins, minerals and pharmaceuticals incorporated with it.
I hope that from my presentation you learned about Cindy Pennington and the contributions she made in animal genetics through the use of embryo transfer and collection.