by Alicia Bosenko

2021 has been a tough year with nationwide droughts and elevated grain prices leading to intense culling and new management decisions for many farms. For many cow-calf producers, the fall marks the period for weaning and pregnancy checking. Annual income is derived from reproductive females and pounds sold of a healthy calf crop. While producers can’t control some market factors like seasonality and mother nature, they can control factors of reproductive health and calf performance starting now with early fetal development and dam health.  As we look forward at increasing hay cost and higher than average grain pricing, it is critical to utilize resources more efficiently and help your females do the heavy lifting.

Fetal programming is a term used repeatedly to highlight the importance of nutritional support throughout gestation to raise a healthier and more uniform calf crop. In the first 90 days of pregnancy, nutritional deficiencies already start to affect placental development and vasculature that will feed the fetus until parturition. As the fetus grows, any nutritional deficiencies of the dam will affect nutrient allocations to the fetus. Muscle development, for example, is a lower priority for nutritional partitioning than brain and heart development. However, there is no net increase in the number of muscle fibers after birth so any nutritional deficiencies in utero will lead to a poorer performing calf, with lower live and lower carcass weights even out to 30 months of age[i]. To ensure the best success of the females and the 2022 calf crop consider evaluating these areas on farm:

Pregnancy Check

Pregnancy checks help to identify females that are open and those that will be outside the calving window for a majority of the herd. In most operations, the calving window is approximately 60 days. This helps to have a uniform calf crop that can be marketed as a larger group. Studies have also shown that calves born earlier in the calving cycle are heavier at weaning than those born on later cycles. Consider culling females that are open, outside the calving window, or who are hard doers – need more feed to maintain a body condition of 5-6.

Test your forages

Testing forages will help identify the best use of your resources. Cows in late gestation and weaned calves will need higher energy and protein sources to meet their nutritional demands. To ensure good body condition into calving and early lactation, as well as with Wisconsin’s coldest months, utilize your better-quality forages in late gestation when 75% of fetal growth is occurring. If possible, consider feeding systems that control intake to minimize waste, optimize forage utilization, and support the cows most effectively.

Offer consistent, quality minerals

Minerals play a critical role in cow health and calf development and not all minerals are created equal. First and foremost, is it palatable? If the cows don’t eat it, they won’t receive the benefits from it. Second, are intakes consistent with the recommended feed rate?  If cows overconsume it costs the producer more money without added benefit. If cows under consume they aren’t meeting their nutrient requirements or the fetus’. Is it a complete mineral? Trace mineral blocks will not offer the same nutritional balance as a complete mineral. What is the mineral source? Sulfates, oxides, and chelated minerals have different costs, but also different bioavailability to the animal. In a 2016 study by Marques, et al.[ii], dams fed an organic or chelated trace mineral had improved hoof integrity and had calves that showed more mineral stores at birth, improved passive immunity transfer, improved health, and had heavier weaning weights. Trace minerals also play a key role in reproductive health of the dam to heal after calving and prepare for the next breeding season. This is critical in maintaining tight calving intervals in future years. A more thorough list of macro and trace minerals and their function to the cow is shown below: