Indicators of Acute Pain and Fly Avoidance Behaviors in Holstein Calves Following Tail-docking

摘要

Previous work showed that the banding process of docking minimally affected mature cows' behavior and physiology, but cutting off the necrotic tail increased haptoglobin. Additionally the docked cows had more flies on the rear legs and exhibited more fly avoidance behaviors. Because many producers dock young calves while they are in hutches where fly problems are more pronounced, we investigated changes in behavior and physiology of young calves following docking by banding. Twenty calves (3 to 5 wk of age) were assigned to a docked or control group, at each of two locations (Indiana and Wisconsin). After applying a band to dock the tail, calves were tested every 15 min for sensitivity to heat below the band at the Indiana location. Calf behavior was recorded for 2 h postbanding and analyzed continuously for that period. After 3 wk, tails were removed and then 1 wk later, fly counts and fly avoidance behaviors were observed at both locations. Tails were sensitive to heat below the banding site, for 60 to 120 min postbanding (mean 87 min). Banded calves were more active than control calves during the 2 h following banding. Percentage of time spent lying was greater for control calves, and the percentage of time spent walking was greater for docked than control calves. More importantly, movements of the head to touch the tail were increased for banded calves (eight-fold more movements). Fly avoidance behaviors directed toward the rear of the calf were evident at noon or in the afternoon. Ear twitches were more frequent for the docked calves and less frequent in the morning for all calves. Licking was more frequent for the docked calves at 1200 and 1600 h. Tail swings were most frequent at 1200 and more frequent for control calves. Two acute phase proteins, haptoglobin and α_1 acid-glycoprotein, were not different at any time. In this study, calves that were banded at 3-wk-of-age showed behaviors indicative of discomfort for 2 h, were attacked by more flies, and showed increased fly avoidance behaviors when docked.