Self-Administration of Meloxicam via Medicated Molasses Lick Blocks May Improve Welfare of Castrated Calves.

Abstract

The self-administration of meloxicam via medicated feed is a novel concept that could enable non-invasive, pre-emptive and long-term analgesia. Forty Bos taurus male calves were randomly allocated to four treatment groups: no castration (PC), surgical castration (NC), surgical castration with subcutaneous meloxicam (M), and surgical castration with medicated lick blocks (ML). Data collection occurred at various timepoints over 13 days following treatment. Plasma concentration of meloxicam was greater in ML compared to M calves at all timepoints except day 1 (p < 0.001); however, variation between ML individuals was high (standard deviation = 1.68). There was no effect of treatment on scrotal diameter or scrotal temperature. Wound morphology scores were improved in ML compared to NC calves. Eating observations were greater in ML calves immediately post-castration, followed by M calves at 3 h post-castration (p < 0.001). ML calves were observed locomoting more (p = 0.0032) and lying less (p < 0.001) than PC calves. These findings indicate that meloxicam-medicated lick blocks may provide a practical option for a longer duration of pain mitigation for surgically castrated calves. Conclusions are limited by the complexities of assessing pain in cattle, and further research into the toxicity effects of continued administration of meloxicam is recommended.