Key health issues for dairy cattle--new and old.

The objective of this paper is to use available information to evaluate the relative importance of various health issues affecting dairy cattle. In addition to traditional ranking using evaluation methods based on impacts to animal productivity, this paper considers zoonotic risks, international trade implications, and animal welfare concerns. Traditional production costs rank mastitis, reproductive problems, and lameness as the top dairy cattle diseases. When the other areas of importance are included, the top-ranked diseases change to include salmonella, Johne's disease, bovine viral diarrhea-associated disease, and mastitis. Researchers in the dairy industry may want to reevaluate their criteria for setting research priorities to include zoonotic risks, international trade implications, and animal welfare concerns.