By Andi Anderson
In cow-calf production, reproductive success is the cornerstone of profitability. For herds to remain sustainable, each cow must deliver a healthy calf every year.
While producers often focus on cows that fail to conceive, fewer recognize the significant impact of pregnancy losses after conception.
Pregnancy loss in cattle is most common in the first trimester. Early embryonic mortality (EEM) refers to pregnancy loss within 30 days of conception. These losses occur in roughly 20–40% of pregnancies. Although frequent, cows experiencing EEM can often rebreed within the typical 60–90 day breeding season, limiting overall productivity loss.
Late embryonic mortality (LEM) occurs between 30 and 90 days after conception. While less common, affecting 3–8% of pregnancies, these later losses present greater challenges.
Cows that lose pregnancies during this period often do not return to heat quickly enough to be rebred in the same season. As a result, the overall calf crop for the herd declines, reducing profitability.
The economic implications are considerable. Each lost pregnancy translates into fewer calves weaned and sold, while producers continue to bear feed and management costs for open cows. Over time, repeated losses erode herd efficiency.
Understanding the causes of late embryonic mortality is vital. Contributing factors may include nutritional deficiencies, infections, stress, or genetic issues. Identifying and managing these risks can help reduce losses and protect herd productivity.
By recognizing LEM as a key challenge, producers can take proactive measures—such as veterinary monitoring, nutritional planning, and careful herd health management—to support reproductive success. Addressing these losses early ensures stronger calf crops and long-term sustainability in cow-calf operations.
Photo Credit: gettyimages-r-j-seymour
Categories: Ohio, Livestock