Downer cow occurrence in Minnesota dairy herds

Abstract

The report contains survey data about occurrence of the downer cow syndrome in 723 dairy herds with 34 656 cow years at risk. Herds were categorized by breed, registration status, and type of housing. For the purpose of this survey, downer cows were defined as being recumbent on the sternum for > 24 h for no obvious reason. The overall incidence of downer cows in the sample was 21.4 1000 cow years at risk. The overall outcome of downer cases was that 33% recovered, 23% were slaughtered, and 44% died. Further specification of data by breed, registration, and time down before recovery, slaughter of death is noted in the text. Owners perceived that downers were high producers (48%) or average producers (46%), with only 6^ being low producers. They reported that 58% of cases occurred within one day of parturition while an additional 37% occurred during the first 100 days of lactation. The number of downers associated with dystocia was 24%, but this was 41% of the cases which went down within one day of calving. The highest incidence of downer cases was during the three coldest months (December–February) when 39% of the cases occurred. In contrast only 16% of cases occurred during the spring months (April–June). A majority of respondents (75%) had experience with hip lifting devices. Of this group 71% found them to be useful for management of downer cows.