In today’s dairy industry, reproductive performance is no longer measured by simply getting cows bred back. With razor-thin margins, profit comes from reducing inefficiencies and obtaining results that are consistent and repeatable. Reproductive management requires more than synchronization protocols alone.
It takes the right hormones, the right team and the right strategy working together to help dairies capture every possible percentage point.
Choosing the Right Prostaglandin
There’s a common misconception that one prostaglandin is basically as good as another. According to Dr. Todd Bilby, Director of Dairy Technical Services at Merck Animal Health, the most important distinctions lie in the product’s active ingredient.
“There’s really only two active ingredients on the market,” Bilby explained. “There’s cloprostenol, which is what ESTRUMATE® (cloprostenol injection) is, and then you have dinoprost tromethamine.”
That difference matters because research has shown ESTRUMATE® maintains a significantly longer half-life compared to dinoprost tromethamine products. Bilby noted ESTRUMATE® remains active for approximately three hours, while dinoprost tromethamine products remain active for only minutes.1,2
The result is a stronger and more consistent response in synchronization programs. Compared to a single injection of LUTALYSE® (dinoprost tromethamine), ESTRUMATE® demonstrated a 3.9% improvement in conception rate in adult cows, an 8.4% increase in heat detection in first-lactation cows and a 33.6% improvement in ovulation rate in heifers. Heifers also reached estrus roughly 15 hours sooner.1,2,4
For producers, those gains quickly translate into economic value.
“Where you really lose money is when you extend your interval to insemination or pregnancy,” Bilby said. “Every day of raising a heifer can cost anywhere from $2 to $4 per day.”
In an environment where margins remain tight, shaving days off the path to pregnancy can have a meaningful effect on overall herd profitability.
Working with the Right Partner
Even the best reproductive products cannot overcome poor transition management, inconsistent protocols or gaps in communication. That is why Merck Animal Health emphasizes a collaborative, whole-herd approach to reproduction.
“The ideal approach is a team approach,” Bilby said. “It’s very important to lay out a plan, hear from all sides and continue to check in with meetings — whether that’s weekly, monthly or quarterly.”
Reps and technical service specialists who know your farm make a major impact. It’s regular evaluations and protocol refinement that can take a dairy from good to great.
Bilby emphasizes that reproductive success begins long before breeding day. Transition cow health remains one of the biggest drivers of reproductive performance. Studies continue to show cows that avoid disease events during transition achieve significantly better conception rates than cows experiencing even a single health setback.
“We have to set that cow up at the right time,” Bilby said. “It starts well before that cow even calves. You have to have proper nutrition, proper health, proper people and proper protocols in order to have the best chance of achieving the highest fertility on your farm.”
Precise Reproduction Through Monitoring Insights
As reproductive programs evolve, producers are seeing distinct advantages from more targeted hormone use supported by herd monitoring technology.
“That next milestone? It’s using technology to really dial in when we use the hormones and where we use the hormones,” Bilby said.
With systems such as SenseHub® Dairy monitoring, producers can identify cows most likely to respond to synchronization protocols based on where they are in their estrous cycle rather than treating an entire pen uniformly.
“When using herd monitoring for targeted synchronization,” Bilby noted, “we can become much more precise.”
That precision has produced measurable results, including a 17.8% improvement in conception rates in heifers and an economic return of $108 per adult cow when targeted synchronization strategies are implemented.2,3
The dairy world has already made remarkable progress. Pregnancy rates once considered unattainable are now becoming routine on many dairies. But that doesn’t mean we’ve reached an end point either. There’s still plenty of progress available with the best tools and a diligent team.
“When I was first coming out of grad school, we were just looking to get to 20% preg rates,” Bilby said. “Now we’re talking 30% preg rates. Each time we’ve reached a milestone, we think it can’t get any better, and yet it always does.”
With the right products, the right people and the right approach, Merck Animal Health knows the premium repro rates are well within reach. Learn more about proven repro performance at Estrumate-Edge.com.
Citations:
1 Veronese A, Marques O, Moriera R, Belli AL, Bilby TR, Chebel RC. Estrous characteristics and reproductive outcomes of Holstein heifers treated with 2 prostaglandin formulations and detected in estrus by an automated estrous detection or mounting device. J Dairy Sci 2019:102(7):6649-6659.
2 Umaña Sedó SG, Figueiredo CC, Gonzalez TD, Duarte GA, Ugarte Marin MB, Crawford CA, Pohler KG, Chebel RC, Bilby TR, Bisinotto RS. Evaluation of luteolysis, follicle size, and time to ovulation in Holstein heifers treated with two different analogs and doses of prostaglandin-F2α. J Dairy Sci 2022 Jun;105(6):5506-5518.
3 Chebel RC, Gonzalez T, Montevecchio AB, Galvão KN, de Vries A, Bisinotto RS. Targeted reproductive management for lactating Holstein Cows: Economic return. J Dairy Sci Feb 2025;108(2):1584-1601.
4 Pursley JR, Martins JPN, Wright C, Steward ND. Compared to dinoprost tromethamine, cloprostenol sodium increased rates of estrus detection, conception, and pregnancy in lactating dairy cows on a large commercial dairy. Therio 2012:78(5):823-829.
IMPORTANT SAFETY INFORMATION
ESTRUMATE: Do not administer ESTRUMATE to a pregnant cow unless abortion is desired. Severe localized post-injection clostridial infections have been reported; in rare instances infection has led to death. Women of childbearing age, asthmatics, and persons with respiratory problems should exercise extreme caution when handling ESTRUMATE. ESTRUMATE is readily absorbed through the skin and can cause abortion and/or bronchospasms; direct contact with the skin should be avoided, and accidental spillage on the skin should be washed off immediately with soap and water. For complete safety information, refer to the product label.
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