Maintaining a high level of reproductive efficiency is required if dairy herd profitability is to be maximized. Reproductive performance of a dairy herd is a function of certain management policies and how well these management policies are implemented in the day-to-day management of the herd.

The first step in evaluating the reproductive performance is to identify key measurements and use them as guides in developing or altering herd management policies and practices. The calving interval should be the starting point in evaluation of prior herd performance. For maximum production, a calving interval of 12.3 to 12.8 months must be achieved. When calving intervals vary beyond this range, milk production drops significantly, with a sharp drop when calving intervals exceed 13.6 months.