For many cattle producers, calving season is coming to an end and breeding season has started. Early gestation is a critical period in the reproductive cycle of beef cattle, laying the foundation for the health, productivity and profitability of both the cow and the developing fetus. Nutrition plays a pivotal role during this stage, influencing reproductive performance, fetal development, milk production and future efficiency. Optimizing early-gestation nutrition ensures the success and sustainability of beef cattle operations.
For a cow to calve annually, she must be bred no later than 80 days after calving. Therefore, cows must have a calf at their side during the breeding season. Compared to maintenance requirements, early lactation increases the cow’s nutrient requirements for protein, energy, calcium, phosphorus, potassium, magnesium and sodium by about 30%. During early gestation, which typically lasts from conception to approximately 100 days, specific attention must be paid to nutrient intake to support embryo survival, implantation, placenta development and early fetal development.
One of the primary nutrients to consider during early gestation is providing enough energy to support the metabolic needs of a lactating cow and her developing fetus. Energy needs will vary based on breed, age, body condition and environmental factors. In general, cows in early gestation will have greater energy requirements than they would in midgestation. Abundant, high-quality forage will usually provide enough energy to maintain body condition. However, an energy-dense supplement such as cake, grains or byproduct feeds may be needed to maintain or increase body condition scores to optimal levels.
Protein is another critical nutrient required during early gestation. External factors like cow age will influence protein requirements. Bred heifers have the highest protein requirement because they are still growing in stature and mass, whereas an older cow will have achieved maturity. Lactation and fetal development will also add to the female’s protein requirement. Maternal protein requirement during this stage can typically be met with good-quality forages; however, supplementation may be required depending on age and time of year in which early gestation occurs.
In addition to energy and protein, cow herd managers should be cognizant of cattle’s micronutrient requirements. Minerals such as calcium, phosphorus and magnesium, along with the trace minerals copper, zinc, manganese and selenium, play key roles in the cow’s reproductive function and the fetus’s development and growth. Mineral deficiencies can lead to reproductive disorders and developmental abnormalities in the fetus. For example, selenium deficiency can alter small intestinal development in the fetus and persist after birth. Nutrient restriction can also result in impaired organ development, including reproductive organs. Providing a balanced mineral that contains bioavailable sources of chelated trace minerals has been proven to eliminate mineral deficiency symptoms.
Moreover, adequate vitamin intake is crucial for supporting overall cow and fetal health and immunity during early gestation. Vitamins A, D and E are particularly important and warrant inclusion in adequate amounts. While cattle grazing on fresh pasture may obtain sufficient vitamin intake, supplemental vitamin sources are necessary, especially during periods of limited forage availability or in regions with poor soil quality.
Grazing cattle in pastures can be a time where meeting nutrient requirements can be difficult due to the nature of an ever-changing environment. Drought-stricken pastures with low forage density or pastures that have an overabundance of moisture can have reduced nutrient content and will require additional supplementation. It is important to know about the environment cattle are grazing so supplementation strategies can be developed to minimize the negative effects compromised nutrient intake can have on fertility and fetal development.
The beef cow body condition scoring (BCS) system is a useful tool to evaluate cows’ body condition coming into the breeding season and during gestation. The BCS system utilizes scores from 1 to 9, with 1 being thin, 9 being obese and 5 to 6 being the ideal body condition. Body condition has a direct relationship with oocyte quality and fertilization rates. Research has demonstrated cows with a BCS of 4 or lower required more services per conception and had around a 60% conception rate. On the other hand, cows that had a BCS of 5 or better had a conception rate above 90%. Monitoring BCS regularly and adjusting feeding strategies as needed can help ensure cows enter the breeding season in optimal condition and support successful conception and early fetal development.
Optimizing early-gestation nutrition is essential to maintaining the health and productivity of beef cattle herds. By providing adequate energy, protein, minerals and vitamins and managing body condition score, producers can support reproductive success, fetal development and the sustainability of their operations. With careful attention paid to nutrition and management practices, beef producers can maximize the potential of their herds and ensure a prosperous future for the beef cattle industry.
