AI used in sheep flocks
By Jennifer Carrico
While artificial insemination is more common in the beef and swine industry, it has also become more popular in the sheep industry recently.
Dr. Tad Thompson, a veterinarian from Sheridan, Ind., travels the countryside to help sheep producers move forward in their genetic advancements.
The technique Thompson uses is called Laparoscopic Artificial Insemination.
"When performing this type of AI, the semen is deposited directly into the lumen of the uterine horns," he said.
Thompson, a Purdue University College of Veterinary Medicine graduate, was able to learn this process by working along side some of the best ovine and reproductive specialists in Australia and England. This technology was first developed in Australia in 1982.
This technology is used with an intense synchronization process with critical timing to get the ewes bred.
Ewes are sedated to keep them still during the process. He also recommends taking the ewes off all feed for about 24 hours in order to make the surgical process easier, allowing him to see all the parts of the reproductive system more easily.
Following the sedation, ewes' bellies are shaved and washed with antiseptic soap. Next, Thompson inserts the scope into the abdominal area to examine the reproductive tract and determine if the ewe is in the proper stage of her reproductive cycle to be artificially inseminated.
If the ewe is in the proper stage, he then determines the proper place to insert the laparoscope and insert the semen into the lumen of the uterus through the use of an assistant.
Thompson usually uses 1/4 milliliter of semen and sometimes 1/2 milliliter of semen to breed the ewe. He prefers to use fresh semen, which is collected from the ram minutes before using AI on the ewes. He can also use frozen semen. In both cases the semen is evaluated for quality prior to use.
After the process, the surgical holes are sealed with an adhesive spray and the ewe is given penicillin to prevent infection.
"Conception rates vary, but for the most part, I average 75 percent when using fresh semen and 65 percent when using frozen semen," he said.
Thompson artificially inseminates about 2,000 ewes each year. The veterinary practice he is in also specializes in embryo transfer of ewes, which is also a surgical process for both the donor ewe and recipient ewe.
"Both AI and embryo transfer allow sheep producers to advance their genetics in a short amount of time," he said.
For more information, visit www.jvcgenetics.com.
Jennifer Carrico can be reached by phone at 515-833-2120, or by email at firstname.lastname@example.org.