May 5, 1999

To maximize milk production, dairy cows must become pregnant and calve each year. Ovarian follicular cysts disrupt the normal reproductive cycle and make it hard for cows to become pregnant. It is one of the most common problems facing dairy farmers.

William Silvia, reproductive physiology specialist at the University of Kentucky's College of Agriculture, is using ultrasound technology to help study ovarian follicular cysts in dairy cattle. He said cysts usually are diagnosed through palpation, or manually feeling, the ovaries.

"Fingers can be crude estimators," Silvia said. "The ultrasound machine is much more accurate. We can measure the size of a cyst to the exact millimeter. This is very important in our research. The machine also allows us to look inside a cyst and study its structure."

Silvia said he and his colleagues started using the ultrasound machine about four years ago.

"I'd say for the first two years we were really just learning how to use it," Silvia continued. "We learned very quickly that we often misdiagnosed cysts. Some other structures on the ovaries can feel like cysts when you palpate. The last two years have been very productive."

Research Technician, Doug Yelton, collects blood samples from cows each day and examines the cysts with the ultrasound three times per week. He and Dr. Silvia measure hormones in the blood samples. They have discovered some hormones are produced at abnormal levels when cysts form.

From their research, Silvia and Yelton have developed, and are now testing, a treatment for cysts. Silvia said early results are very promising. Also, Silvia will know in June if he will get a USDA grant to further study the problem.

The machine is expensive. At more than $10,000, the ultrasound machine is not likely to be something dairy producers will buy for their own use. Ultrasound widely is used in the equine industry, but is much less common with cows. For now, dairy farmers will benefit from the ultrasound machine's use as a research tool.


Writer: Aimee D. Heald (606) 257-9764
Source: Bill Sylvia (606) 257-7537