Interpretive Summary: Impacts of stress on growth and reproductive development of beef heifers

By: Kelsey M Harvey, Reinaldo Fernandes Cooke, Brooklyn L Laubinger

Implications

• Beef heifers with excitable temperament exhibit reduced growth rates and delayed puberty attainment.
• Beef heifers that are acclimated to human handling have accelerated reproductive development and conceive earlier in the breeding season.
• Rearing beef heifers in drylots with a high stocking density stimulates chronic stress and reduces physical activity, resulting in delayed puberty attainment.
• Exposing replacement beef heifers to moderate exercise regimen partially alleviates the detrimental effects of elevated stocking density on puberty attainment.

Introduction

The success of cow-calf operations is fundamentally tied to the performance and management of beef females, as they are expected to maintain estrous cyclicity and produce one calf per cow annually. A combination of factors, including nutrition and management practices, affect reproductive success in cattle, and therefore overall fertility and herd performance. Replacement heifer development is a cornerstone the cow-calf sector, as these young females offer a valuable opportunity to introduce new genetics to advance herd productivity and profitability. The value of a replacement heifer lies not only in her genetics but also in the management practices employed during her development postweaning. Properly developing replacement heifers involves optimizing nutrition, health, and management to ensure they reach puberty in a timely manner. Proper development of young females before they reach puberty supports herd sustainability and prevent financial losses, as reproductive inefficiency accounts for the culling of approximately one third of a typical cowherd (USDA, 2020)

Read the full article in Animal Frontiers, Factors Affecting Animal Growth.