Behavioral and Physiological Response to Routine Thermal Disbudding in Dairy Calves Treated with Transdermal Flunixin Meglumine

SIMPLE SUMMARY: The practice of disbudding calves is common in the dairy industry, and the desire to mitigate pain caused by the procedure has resulted in questions as to whether all treatments are equally effective. The goal of this study was to investigate the effectiveness of a new product, transdermal flunixin meglumine, as part of a multimodal pain management protocol as compared to routinely used protocols. We determined that a pain management protocol utilizing transdermal flunixin meglumine and lidocaine was not significantly different than a protocol using meloxicam and lidocaine, or lidocaine alone, when comparing targeted calf behaviors and measuring salivary cortisol. This information can be used by veterinarians and producers to help guide them in choosing the appropriate pain management strategy for calves on their farms. ABSTRACT: Transdermal flunixin meglumine was approved in 2018 to treat pain related to foot-rot in cattle, leading to the question of whether it would be effective as part of a comprehensive pain management strategy for disbudding. To investigate, calves were assigned to three treatment groups: 2% lidocaine cornual nerve block only (L), lidocaine nerve block +0.45 mg/lb (1 mg/kg) oral meloxicam (M), or lidocaine nerve block +1.5 mg/lb (3.3 mg/kg) transdermal flunixin meglumine (F) (n = 61). Ear flicking (p = 0.001), head shaking (p < 0.001), tail flicking (p < 0.001), interaction with the environment (p < 0.001), grooming (p < 0.01), posture changes (p < 0.05), and standing (p < 0.001) were impacted by the time relative to the procedure. Cortisol levels rose post procedure (p < 0.001). There was no difference in rates of behaviors or cortisol between treatments. These results indicate that calves showed alterations in behavior and cortisol in response to disbudding but not between treatments. We conclude that the pain management protocol for disbudding, which included transdermal flunixin meglumine with a lidocaine cornual nerve block, did not show significant differences from protocols using meloxicam with a lidocaine block, or a lidocaine block alone.