Papillomatous digital dermatitis and associated risk factors in US dairy herds

The objective of this study was to describe the incidence of papillomatous digital dermatitis in the US (including regional and herd size patterns) an d to evaluate specific herd-level management factors associated with high i ncidence of digital dermatitis in US dairy herds. The study design was a po pulation-based cross-sectional survey. US daily operations with at least 30 cows in 20 states, representing 79% of US dairy cows, were sampled. On par ticipant operations;a questionnaire was administered by veterinary medical officer or animal-health technicians on-farm to dairy managers. Papillomatous digital dermatitis was reported in milk cows in the previous 12 months from 43.5% of US dairy herds. Seventy-eight percent of affected h erds reported that their first cases occurred in 1993 or later. Regions of the USA with the highest percent of herds affected included the Southwest, Northwest, and Northeast. Factors associated with high (>5%) incidence of p apillomatous digital dermatitis included region, herd size, type of land la ctating cows accessed on a daily basis, flooring type where lactating cows walked, percent of cows barn off the operation, use of a primary hoof trimm er who trimmed cows' hooves on other operations, and lack of washing of hoo f-trimming equipment between cows. Papillomatous digital dermatitis has been recently reported from dairy herd s across the US. This study suggests that a high percentage of herds with d igital dermatitis could be prevented. Management strategies to potentially prevent or reduce incidence of digital dermatitis on dairy operations inclu de those related to biosecurity and 'cow hoof' environmental conditions. Pu blished by Elsevier Science B.V.