Poor reproductive efficiency is one of the most costly problems facing the dairy industry.

According to a USDA report, reproductive problems are one of the most common reasons for culling in U.S. dairy herds.

It is no surprise that reproductive performance should be a top priority for producers. Fertility in dairy cows has steadily declined for the past 20 years and making a profit depends heavily on the ability to breed cows efficiently and effectively in both the beef and dairy segments.

Reproductive problems can significantly cut profits in a herd. A missed heat cycle can cost as much as $29, and a missed pregnancy costs an average of $450. This is why it is important for producers to help cows conceive and calve on schedule.

One of the major causes of reproductive failure reported on farms is ovarian follicular cysts. Ovarian cysts can cause overexpression of heat, irregular cycling and can cause the cow to become infertile. A GnRH can help keep ovaries healthy by clearing out these ovarian cysts that may be standing in the way of getting a cow pregnant.


In a 2007 study of dairy producers, almost 70 percent reported having instances of cystic ovaries occur in their herd. This condition is estimated to affect at least 1 million dairy cows in the U.S. annually. It also is a major cause of infertility and economic loss on farms because cows are infertile as long as the condition persists.

Ovarian cysts occur when a follicle has persisted more than 10 days and has become larger than two centimeters in diameter. GnRH helps rid the ovary of that follicle so a new one can take its place, which activates the process leading to estrus.

By treating ovarian cysts, GnRH serves two important functions that cause the ovulation of a dominant ovarian follicle. GnRH causes the pituitary gland to secrete both luteinizing hormone (LH) and, to a lesser extent, follicle stimulation hormone (FSH). LH, in concert with other changing levels of hormones, causes ovulation.

Management choices affecting reproduction can be the deciding factor between ending the year in the black, or falling into the red. Producers should make sure they are using a trusted GnRH product to help treat ovarian follicular cysts and boost reproduction performance. PD

References omitted due to space but are available upon request by emailing editor@progressivedairy.com .

Tom Van Dyke