Last November marked the 20th anniversary of the first publication on Ovsynch by J.R. Pursley, M.O. Mee and M.C. Wiltbank. It has been cited in 1,161 journal articles since. That article, in Theriogenology, introduced the idea that ovulation could be synchronized in an eight-hour period to potentially allow for acceptable fertility following fixed-time A.I. in dairy cows.

Your best cow is in standing heat this morning. Just two weeks ago, she was diagnosed pregnant. Bummer! The first thing you want to do is find someone to blame. Usually, the veterinarian is first on the list. Just so you know, it is not likely to be the veterinarian’s fault. Please don’t blame the veterinarian.

Breeding cows back in a timely manner hinges upon that first estrous cycle after calving, but sometimes the return to estrus is delayed. However, there are things you can do to identify and manage these cows and improve your herd’s pregnancy rate.

Are there technologies now, or potentially in the future, that will be more cost-efficient to drive pregnancy rate equivalent to or greater than current synchronization or fertility programs?

Many dairy veterinarians prescribe the use of prostaglandin F2α (PG) in dairy herds to control time to estrus (heat), as part of synchronization programs or for postpartum treatments. There are two primary PG products available in the U.S., dinoprost tromethamine (Lutalyse and generic ProstaMate) and cloprostenol sodium (Estrumate and generic estroPLAN). These two products are different in chemical structure and have a different half-life. Cloprostenol has a longer half-life than dinoprost, and thus is maintained in circulation for a longer time. But are they different when it comes to performance in the field? We have completed several studies that indicated there were subtle differences. This article will discuss the pros and cons of these two products.

TRENDING TOPIC ARTICLE: A.I. & BREEDING In this article, Michigan State University’s J. Richard Pursley explains how a simple adjustment of cycle days in a presynch/ovsynch program could have a dramatic effect on a herd’s fertility and a producer’s bottom line. to jump to the article.

The lactating dairy cow is not as fertile as she once was. And the likely culprit is not going to go away. But wait, there’s hope for ol’ Bessie. This story will outline the likely reasons for the decline of dairy cow fertility and discuss reproductive management methods to help alleviate this problem.