Relationship of Reproductive Factors with Interval and Rate of Conception

Abstract

The relative importance of several reproductive traits on the variation in interval and rate of conception was determined. The average conception interval of all cows was 146 days, or 122 days excluding 49 open infertile cows that were assigned arbitrarily a maximum 308-day conception interval. Conception rate was 87%. Least squares models, including the fixed effects of season, parity, uterine involution grade, ovarian condition, retained placenta, dystocia, embryonic deaths, reproductive treatment, and times bred, explained 75% of the variation in conception interval and 71% of the variation in conception rate.