Fall is a busy time of year for many operations, with harvest, preparing for winter, weaning calves and cow management all on the agenda. Pregnancy-testing the herd is an important management tool that can provide a good metric for herd health and production, evaluate individual cow health status, and influence marketing options for open cows.

Pregnancy-testing early in the fall can provide additional value by increasing the time to implement management changes identified during this evaluation and modifying the marketing options for open cows.

Monitoring H&P

Early pregnancy-testing provides a barometer for herd health and production (H&P), allowing managers to implement necessary changes prior to winter months. The overall pregnancy rate and number of animals bred in the first 21 days are great measures of overall herd health and nutritional status.

Pregnancy evaluations should be performed at a time when pregnancies can be aged, which is typically four or five months from the start of the breeding season.

An early pregnancy test allows accurate determination of whether the percentage of cows bred in the first 21 days of the breeding season is close to the target goal of 65%. This goal is based on the biological reality that when fertile bulls breed cycling cows, we expect a 65% conception rate based on one breeding event.

When fertile bulls breed cycling cows, we expect a 65% conception rate based on one breeding event. 

If the herd has 65% bred in the first 21 days, then we can conclude that the bulls were fertile and all the cows were cycling at the start of the breeding season. This indicates the previous year’s nutritional program was adequate and there have been minimal disease challenges in the herd.

The overall pregnancy rate is also indicative of overall herd health and production, with a target range of 90% to 95% pregnant within a 65-day breeding season. Longer breeding seasons are acceptable; but, to evaluate overall herd health, monitoring the pregnancy rate at 65-plus days provides a comparable metric. If the pregnancy rate is lower than 90%, further investigation should be considered to identify potential reasons contributing to the lower breeding percentage.

These evaluations may start by identifying any commonality between cows that did not breed in the first 21 days or over the entire period. Cow-calf operations have a long production cycle. Early evaluation of pregnancy rate, a key production metric, is critical to monitoring cow efficiency.

Health status

Individual cow and herd status can also be evaluated at the time of preg-testing. It provides a good time to evaluate general health and measure body condition score (BCS).

General health evaluations of adult cows can reveal disease processes such as cancer eye and musculoskeletal disease early in developmental stage, facilitating more effective interventions. Depending on their condition, animals may need to be removed from the herd prior to the winter months.

Recording BCS at preg check provides an overview of current herd nutritional status. Lower BCS scores may be expected in some animals, as calves are still nursing and summer grasses may be decreasing in quality. An accurate depiction of current body condition allows creation of a nutritional plan for the fall and winter months to accurately allocate nutritional resources.

Marketing opens

Early identification of nonpregnant females allows more options for marketing of open cows. The sooner open cows are removed from the base herd, the fewer resources will be used for animals that will not produce a calf in the next year. An early pregnancy test can identify and remove open cows to conserve fall grazing resources for pregnant cows.

While open animals or culls are sometimes viewed as losses from the operation, identifying the best marketing alternatives for these animals is important as they contribute approximately 20% of the average cow-calf operation’s gross income.

Nationally, about two-thirds of cow-calf herds calve in the spring, commonly leading to weaning and preg-testing in the fall. This results in most open cows marketed in late fall, which leads to seasonally lower prices. Early preg-testing can allow operations to market cull cows prior to seasonal price declines.

Alternatively, based on resource availability, producers can enlist methods to add value to nonpregnant cows. One option is feeding cows through the fall to add weight prior to selling. If the open animals are young and in good shape, another opportunity is rebreeding those females to market as pregnant animals, which typically command a higher price.

Selecting the best option for each ranch depends on the number of open animals, the reasons they were open and the resources available. Early pregnancy-testing creates multiple options for marketing open cows.

Conclusions

Preg-testing is an important management tool for cow-calf producers. Preg-testing early can help evaluate both herd and individual animal health status in addition to improving marketing options for open cows.

Editor’s note: Author Brad White is on faculty at Kansas State University College of Veterinary Medicine and serves as director of the Beef Cattle Institute. To learn more on this and other beef herd health topics, tune in to the weekly Beef Cattle Institute Cattle Chat and Bovine Science with BCI podcasts available on iTunes, GooglePlay or directly from www.ksubci.org.