Interpretive Summary: Effect of subcutaneous meloxicam on indicators of acute pain and distress after castration and branding in 2-mo-old beef calves
By: Megan LaFollette
In June 2018, Journal of Animal Science published an article that investigated using a single dose of meloxicam to help with pain resulting from castration in 2-month-old beef calves. Castrating cattle is a common husbandry procedure used to improve meat quality, reduce aggression, and increase on farm safety. Most commonly, calves are castrated using a knife. Simultaneously with castration, other procedures such as hot-iron branding are completed to reduce calf handling. Unfortunately, both castration and branding are painful events that have negative effects on growth, behavior, and physiology. Currently, neither of these methods are usually carried out with any sort of pain-relief. Injectable meloxicam is a possible practical pain-relieving anti-inflammatory drug that could mitigate painful husbandry procedures. This study’s objective was to assess the effectiveness of meloxicam for reducing acute pain during castration and castration + branding in 2-month-old beef calves.
In this study, 71 Angus crossbred beef calves were tested with 3 castration methods (control/sham, knife castration, or knife castration + branding) and 2 medications (control/lactated ringers or meloxicam). This meant there were 6 treatment groups: sham with ringers, castration with ringers, castration + brand with ringers, sham with meloxicam, castration with meloxicam, and castration + brand with meloxicam. Meloxicam was given at a dosage of 0.5 mg/kg bodyweight. Calves were knife castrated and branded on a tipping table while lying on their left side. Sham calves were handled in a similar manner but without actual castration or branding. Calves were assessed for physiology, performance, and behavior.
Meloxicam administration influenced some measures of calf behavior and physiology. For behavior, calves administered meloxicam had a longer lying duration and fewer tail flicks 2-4 hours after the handling procedure. For physiology, on day 2, calves that were administered meloxicam after castration or castration + branding, or received control handling, had lower haptoglobin than calves that did not receive meloxicam during castration or castration + branding. On days 1 and 3, calves that were administered meloxicam during castration or castration + branding, or received control handling, had lower haptoglobin than calves that did not receive meloxicam during castration + branding. The administration of meloxicam did not effect any other physiological (e.g. salivary cortisol, substance P, serum amyloid-A) or behavioral (e.g. stride length, eating, standing, walking) parameters.
Type of procedure also influenced some measures of calf physiology and behavior. For physiology, from 90 minutes on, calves that castrated and branded had the highest cortisol followed by calves that were just castrated, and finally control calves. At 60 minutes after the procedure, both castrated and castration + branding calves had greater cortisol than control calves. For behavior, on day 2, calves that received castration + branding had the most tail flicks followed by castration only and then controls. On days 1 and 3, calves that received castration + branding or castration only had more tail flicks that control calves.
Overall, this study suggests that injectable meloxicam administered subcutaneously may be beneficial for reducing some indicators of acute pain during castration and branding. For husbandry procedures, the combination of knife castration and branding is more painful that knife castration alone. However, both knife castration alone and with branding did still negatively impacted calf physiology and behavior.
To view the full article, click here.