Dairy Herd Fertility Examination of Genetic Merit Effects

This technical report examines the effects of increasing genetic merit and other herd factors on reproductive performance in dairy herds in Northern Ireland. The report outlines the significant issue of infertility in dairy herds, which results in considerable financial losses, estimated at approximately £50 million annually. It discusses traditional methods of assessing fertility performance and the need for a review of these methods to ensure they are meaningful and applicable across various farms. The report proposes the adoption of the In-Calf Rate (ICR) as a measure of reproductive performance, detailing the target rates for herds with different calving patterns. Additionally, it presents a comprehensive research program initiated to identify key factors influencing reproductive performance, including management practices, nutritional factors, and genetic trends. The findings reveal a range of causes for infertility and emphasize the importance of good record-keeping, hygiene, and effective heat detection and insemination techniques to improve reproductive outcomes.