EFFECT OF CASTRATION AND ORAL MELOXICAM ON INFLAMMATION, ANIMAL BEHAVIOR, AND GROWTH PERFORMANCE IN BEEF CATTLE

Castration is a common, yet painful management practice that is utilized by beef producers throughout the United States. There has been an increase in public concern for welfare within livestock species that warrants further investigation into pain mitigation practices that could be implemented during castration. Three studies were conducted to investigate the use of meloxicam, a non-steroidal anti-inflammatory drug, and its effect on inflammation, growth performance and behavior in castrated beef cattle. Study one utilized thirty yearling crossbred bulls assigned to three treatment groups including surgical castration with or without meloxicam administration and intact males used as positive controls. This study indicated that oral meloxicam administration at 1 mg/kg BW reduced inflammation and the stress response, while delaying the febrile response after castration. Study two was conducted to evaluate meloxicam administration in younger-aged beef bulls. Eighty-three crossbred beef bulls averaging 68 days of age were utilized in this study and were randomized into 1 of 3 treatments: intact bulls serving as positive controls, surgical castration and surgical castration with 1 mg/kg BW oral meloxicam administration. This study suggested that meloxicam administration in younger bulls does not clearly alter the immune response or animal behavior. Meloxicam administration did improve ADG for the first two weeks post-castration; however, BW was not different following castration. Study three was conducted using yearling bulls entering the feedlot to evaluate the effect of castration method and meloxicam administration on animal performance, behavior, carcass traits and inflammation. This study was conducted over a
3 year period and consisted of a total 194 crossbred beef bulls assigned to 1 of 5 treatments: negative control animals that were castrated near birth, surgical castration with or without meloxicam administration, and band castration with or without meloxicam administration. Animal performance was affected by method of castration; surgical castration reduced performance compared to band castration in the first week post-castration, while band castration reduced performance in the second week post-castration. Average daily gain for the entire study was not different with castration method; however, meloxicam administration did improve overall ADG compared to castrated controls, regardless of method. Meloxicam administration also improved several carcass traits compared to castrated control animals. Animal behavior, the first week post-castration, was altered with castration. The method of castration had differing affects with surgical castration causing increased standing time, while band castration increased the number of steps and the number of lying bouts post-castration. Haptoglobin concentration was also reduced for band castration compared to surgical castration with meloxicam mitigating the magnitude of haptoglobin concentration in surgically castrated animals. These studies indicate that meloxicam may be an effective pharmacological method to reduce pain and inflammation in yearling-age castrated beef cattle; whereas, the method of castration had divergent behavior and performance responses but neither method is clearly advantageous.