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Knowing Open Cows More Important Than Knowing Pregnant Ones

Taylor Leach



“She’s open.”


Say those two words to any producer and you’re almost guaranteed to see them scowl. Unfortunately, it’s a phrase dairy farmers hear all too often. 


While it might be frustrating to find an unexpected open cow in the herd, knowing that information is important. In fact, the most important controllable component of any breeding program is to identify your open cows, according to Donna Amaral-Phillips, extension professor at the University of Kentucky.


“The earlier [open] cows are identified, the quicker they can be rebred to decrease the number of days open,” Amaral-Philips says in a recent University of Kentucky extension article. “The goal is to have as many cows pregnant as possible by the time they are less than150 days in milk.”


A lost pregnancy is not only frustrating , but it can cause long-term financial impacts, too. Financial losses can come from decreased milk production, an increased cull rate, increased semen expense, veterinary expenses and over-conditioned cows. 


“The more cows with extended days open, the greater the total cost,” Amaral-Philips says. “No great surprises here. But, closing this gap in getting cows bred and pregnant is a controllable management component.”


Two simple ways to better monitor your number of open cows is to establish routine heat detections and pregnancy checks.



The first step to getting pregnant is to know when they need to be bred. 


“Heat detection can be accomplished through routine, planned visual observation (three, 30-minute observation periods daily), use of heat detection and or through an activity monitory system,” Amaral-Philips says. “Maintaining and using production and breeding records can also aid in determining the best day in milk to start breeding a cow and whether or not they have been bred before.” 



Conducting routine pregnancy testing is recommended for herds every two to six weeks to help determine if previously pregnant animals have come in as open. Amaral-Philips suggests working with your veterinarian to select the best frequency at which animals should be tested.


“Routinely having a veterinarian palpate or ultrasound bred cows or collecting milk or blood for testing for compounds associated with a pregnancy is the best way to determine cows which are open, not whether they have not come back in heat,” Amaral-Philips says.

dairyherd.com