Effects of an herbal tincture therapy and willow bark (Salix extract) on the physiological and behavioral response to disbudding in dairy calves under organic management.

Disbudding is a standard procedure on most US dairy farms, but organic options to alleviate pain are limited. The objective of this study was to assess the post-disbudding analgesic effects of 2 organic pain relief methods (Dull It, Dr. Paul's Lab, Mazomanie, WI; willow bark, Nature's Way, Green Bay, WI) on the heart rate, ocular temperature, salivary cortisol concentration, and lying behavior (time, bouts, and bout duration) of 53 preweaning Holstein and crossbred dairy calves born at the West Central Research and Outreach Center in Morris, Minnesota. Calves were disbudded with a cautery iron between 5 and 7 wk of age (44 ± 4 d) and randomly assigned to 1 of 3 treatments: lidocaine only (LA; 5 mL per horn bud; n = 18), lidocaine and Dull It (DI; 5 mL under the tongue immediately after and 1 h after disbudding; n = 18), and lidocaine and willow bark (WB; 200 mg/kg; n = 17). Polar H10 heart rate monitors recorded heart rates for all calves continuously throughout the 5-h study period and data were analyzed in 5-min intervals. The HOBO loggers recorded lying behavior for 95-h following disbudding in 1-min intervals. Thermal images of the eye were captured approximately every 20 s beginning 5 min before and ending 5 min after disbudding for all calves. Saliva samples were collected from 30 randomly selected "minimally invasive" calves 1 h before disbudding, at the time of disbudding, and at 5 min, 10 min, and every 30 min until 240 min after disbudding. The remaining 23 calves served as a "noninvasive" group to control for stress caused by repeated sampling. The mean heart rate of DI calves (132.9 ± 2.2 beats/min) was lower than that of calves in the WB treatment (141.9 ± 2.5 beats/min) during the 4 h following disbudding. The LA calves (136.2 ± 2.4 beats/min) had similar heart rates to both the DI calves and WB calves. Treatment group did not affect ocular temperature, salivary cortisol concentration, and lying behavior. These findings indicate that DI and WB offer little to no analgesic effect. This research highlights the urgent need to find effective alternative options for pain mitigation in organic dairy production.