Factors Affecting Reproductive Performance of Dairy Cows

Abstract

Two studies were conducted to determine how herd management practices and traits of individual cows affected performance of the herd and of the cow within a herd. Management practices, reproductive performance of the herd and relationships between management and reproductive performance were characterized on 83 dairy farms with 7596 cows. Data included 21 management variables (e.g., facilities, herd health program, estrous detection program) and 8 performance variables obtained from Dairy Herd Improvement or unofficial records (e.g., size of herd, production day open). Although varying among herds, annual average herd incidences of reproductive disorders and reproductive performance were similar to those reported. Managerial practices influenced incidences of retained placenta and uterine infection, days open of cows not bred and of all cows, services/conception and percentages of herd open > 100 days and culled for low production. Veterinarian was the most consistent variable influencing herd reproductive performance. Data also were collected from production and lifetime records of 2532 cows in 19 herds. Reproductive performance was affected by season of calving, production, maturity and reproductive disorders. Several cows with poor reproductive records were maintained.