PSLBI-23 - Effects of peri-castration pain management strategies on feed and water intake, performance, and blood cortisol levels of weaned beef steers

Abstract: Objectives of this study were to identify if pain management strategies at the time of castration impact feed and water intake, performance, or blood cortisol levels in weaned beef steers. Thirty black Angus and Simmental Angus cross bulls (Average 8 ± 1 mo, BW=272 ± 45.5 kg) were randomly assigned to 1 of 3 treatment groups: 1) Control (CON; n=10 bulls), castrated via banding; 2) Analgesic (M; n=10 bulls), received an analgesic (meloxicam; 1 mg/kg BW) immediately after banding; and 3) Anesthetic + analgesic (ML; n=10 bulls), received an intra-scrotal and intra-cord anesthetic (total lidocaine 15-20 ml + 10% sodium bicarbonate) injection immediately prior to banding and an analgesic (meloxicam; 1 mg/kg BW) immediately after banding. Blood collections to measure blood cortisol levels were taken on days -7, -0, +0 (day of castration pre- and post-procedure, respectively), 1, and 8. Data were analyzed as repeated measures using the MIXED procedure of SAS with treatment, day, and their interaction as fixed effects and animal as a random effect. While administering analgesics or anesthetics may reduce discomfort, the results of this study showed that these pain management practices do not significantly impact (P ≥ 0.07) on feed (CON = 7.41 ± 0.27 kg; M = 7.72 ± 0.27 kg; ML = 8.06 ± 0.27 kg) and water intake (CON = 20.90 ± 0.69 kg; M = 23.04 ± 0.69 kg; ML = 22.58 ± 0.69 kg), performance (CON = 345.40 ± 12.09 kg; M = 356.97 ± 12.09 kg; ML = 331.93 ± 12.09 kg), or blood cortisol levels (CON = 1.01 ± 0.19 ug/Dl; M = 1.19 ± 0.19 ug/Dl; ML = 1.38 ± 0.19 ug/DL). These data indicate that peri-castration pain management strategies can be adopted at the producers’ managerial discretion.