The objective of this study was to characterize opinions and practices of Wisconsin dairy producers about biosecurity and animal well-being. Wisconsin dairy producers were surveyed using a mailed questionnaire and responder herds were categorized based on the number of lactating cows: very small herds (<= 50 lactating cows; n = 279); small herds ( 51 to 100 lactating cows; n = 202); medium herds ( 101 to 200 lactating cows; n = 42); and large herds (> 200 lactating cows; n = 37). Producers from large herds adopted more biosecurity practices than those from small herds, but biosecurity risks were common. Almost half of the responders indicated that they purchased cattle, but few (49.4%) performed diagnostic testing of those cattle. The frequency of diagnostic testing and examination of purchased cattle increased with herd size. Producers generally (80%) believed that they used the "right amount" of antibiotics, but the use of written treatment protocols increased with herd size. Producers from large and medium herds reported much higher usage of computerized (65.7 and 17.5%, respectively) and paper records (42.9 and 22.5%, respectively) compared with producers from smaller herds. Almost all (92.6%) believed that Johne's disease was an important issue for the dairy industry, but only 9% had enrolled in the official Wisconsin control program. Most producers (88.6%) believed that dehorning caused at least a small amount of pain, but the majority (81%) did not use local anesthetics. Producers minimized risks with which they were most familiar. Drinking raw milk was not considered a human health risk by almost half the responders, whereas bovine spongiform encephalopathy was considered "no risk" to only 37%. Raw milk was consumed by more than 60%, but regular consumption of raw milk decreased from 47.7% ( very small herds) to 24.3% ( large herds); perception of the risk of raw milk increased from 46.2% ( very small herds) to 56.8% ( large herds) with herd size. Larger farms had more knowledge of personal health risks related to zoonotic pathogens. Overall, most management practices were associated with herd size, but many beliefs regarding important dairy farm issues were consistent.
