Checking cows for pregnancy is nothing new, yet its adoption rates are still incredibly low. According to the 2008 United States Department of Agriculture (USDA) survey on cow/calf management practices in the U.S., only 18 percent of all operations and 58 percent of operations with 200 head or more check cows for pregnancy status. The USDA is currently conducting an update to this survey. My hope is that we see adoption rates for this practice increase because there are many benefits to pregnancy checking and multiple options available to do so.
Knowing the pregnancy status of the cow creates additional management options. It essentially gives us a glimpse into the future so that management options can be analyzed and implemented now rather than several months from now. Maintaining an open cow for a year is rarely a sound decision. An open cow can be sold, retained as a stocker cow, or transitioned to a different calving season such as spring to fall. This knowledge allows the producer to make the best management decision given current market conditions. Without this knowledge, the producer is forfeiting a large amount of management control and potential profit.
Other potential benefits based on the method chosen are the ability to sort early calvers from late calvers, determine sex of the calf, identify reproductive abnormalities and provide time with your veterinarian to discuss overall herd health. The latter benefit may become more important for some individuals as the need for a veterinary feed directive goes into effect for some products in 2017.
There are three very good options for determining pregnancy in females: 1) rectal palpation, 2) ultrasound and 3) blood testing.
Rectal palpation is likely the most recognized method by producers. It gives immediate results so that animals can be sorted out of the chute. Accuracy of this method is generally very high at 45 to 60 days post-breeding. A downside is that the skill level of the technician must be accounted for.
Ultrasound is another method and displays higher accuracy slightly earlier at 28 to 35 days post-breeding. It also gives immediate results so that animals can be sorted out of the chute. In addition, this method gives the ability to determine sex of the calf.
Both rectal palpation and ultrasound allow the technician to physically evaluate the reproductive tract and estimate age of the fetus.
Another method is the BioPRYN blood test. This method essentially removes the variable of operator skill level. The test's ability to detect open females is 99 percent accurate, and its ability to detect bred females is 95 percent accurate. The blood must be drawn at least 28 days post-breeding and 75 days post-calving. The biggest advantage is the ease in which producers can learn to pull blood themselves and perform the test as their schedule allows. Downsides of the test are that all females must be individually identifiable. Since the blood must be tested, sorting out of the chute is not an option. Results are generally available within a couple days. Knowledge gained from this test is more limited than rectal palpation and ultrasound. It simply reports a female as bred or open.
The three methods are generally competitive in price. The most important thing is that producers determine what information they want to ascertain through pregnancy checking, then choose the method that provides this information while being logistically feasible.