Reproductive record analysis.

Nationally, over 25,000 herds with more than 4 million cows participate in a Dairy Herd Improvement Association (DHIA) testing plan in conjunction with a Dairy Record Processing Center (DRPC) [1]. Countless other herds use on-farm record keeping systems to maintain information. Technological advances continue to enhance the ease and speed at which information can be recorded, transmitted, and processed, and have made records very accessible for analysis beyond interpretation of mailed test-day reports. A systematic approach to the analysis of reproductive records can yield quality information to enhance herd visits in promoting health and productivity of herds serviced by veterinarians. This article describes methods for interpreting DHIA reproductive performance data generated by off-farm DRPCs in the United States. Procedures described here have been used with data generated by two of five DRPCs listed by the Animal Improvement Programs Laboratory of the United States Department of Agriculture. The methods should be applicable using data generated by other DRPCs—although there are subtle differences among DRPCs in calculating some of the reproductive measures described, they are largely uniform because procedures and calculations are approved by DHIA [2].