Effect of castration method and analgesia on inflammation, behavior, growth performance, and carcass traits in feedlot cattle

Abstract

Our objective was to determine the effect of castration timing, method, and use of the analgesic meloxicam (MEL) on inflammation, behavior, performance, and carcass traits in feedlot cattle. This study was a randomized complete block design conducted over a 3-yr period. In total, 194 crossbred beef calves from a single ranch origin were randomized at birth to receive one of five treatments arranged as a 2 × 2 + 1 factorial: 1) bulls castrated within 48 h of birth (CON), 2) bulls surgically castrated on day 0 without MEL (SUR), 3) bulls surgically castrated on day 0 with MEL (SUR + MEL), 4) bulls band castrated on d 0 without MEL (BAN), and 5) bulls band castrated on day 0 with MEL (BAN + MEL). Upon feedlot arrival (day -11; average 287 ± 2.03 d of age), animals were blocked by initial BW (224 ± 4.5 kg) and assigned randomly to treatment pens in three consecutive years (n = 2 pens per treatment in each year). Oral MEL was administered at 1 mg/kg BW concurrent with applicable castration treatment on day 0. Data were analyzed using the MIXED and GLIMMIX procedures of SAS with pen (year) serving as experimental unit. From days 0 to 7, ADG was reduced (P = 0.01) for surgical (-0.42) compared to band (0.43 kg/d) castration. Conversely, ADG was increased for surgical (1.74) vs. band (1.46 kg/d) castration from days 14 to 32. There was also an overall (day 0 to final) improvement in ADG for MEL (P = 0.02), but no effect of castration method was observed (P = 0.81). The CON group had the greatest (P = 0.05) marbling score. Backfat thickness was increased (P = 0.01) for MEL. A treatment × day interaction (P = 0.04) existed for serum haptoglobin, with SUR having the greatest (P < 0.01) concentration on days 1 and 4. Meloxicam administered in the surgically castrated treatment reduced (P = 0.01) serum haptoglobin concentration on day 1. Relative to baseline, standing duration for surgical castration was increased 113 min (P < 0.01), while banding caused 6.7 more lying bouts (P < 0.01) immediately following castration on day 0. Step count was greatest for BAN, intermediate for CON, and least for surgical (P < 0.01). Results suggest that MEL mitigated the more pronounced inflammation observed for surgical castration, whereas behavior was differentially altered for castration method indicative of a divergent pain response. Castration, regardless of method, transiently reduced ADG, but MEL administration improved overall ADG for both methods.

Effect of a single dose of subcutaneous meloxicam prior to band or knife castration in 1-wk-old beef calves: II. Inflammatory response and healing1

“…Brown et al (2015) observed an increase in lateral lying duration in calves administered oral meloxicam; however, they could not identify if this change in behavior was related to pain or contentment. In contrast, Roberts et al (2018) did not find changes in standing or lying time among castration methods for the first 7 d after administration of an NSAID in weaned calves. However, Roberts et al (2018) found that a motion index indicative of the calf's pain response was reduced in surgical castrated animals administered oral meloxicam.…”

“…In contrast, Roberts et al (2018) did not find changes in standing or lying time among castration methods for the first 7 d after administration of an NSAID in weaned calves. However, Roberts et al (2018) found that a motion index indicative of the calf's pain response was reduced in surgical castrated animals administered oral meloxicam. Similarly, Petherick et al (2014) observed that calves castrated at weaning and administered ketoprofen spent more time feeding and had reduced tail flicks compared with NM calves on the day of castration.…”

“…4-mo-old calves. However, Roberts et al (2018) found Hp concentrations were greater in calves castrated on arrival to the feedlot, which may be associated with greater scrotal damage and inflammation experienced in older calves. Moreover, in this study, CBCs were found to be within the normal ranges for WBC, RBC, platelet count, and N:L ratio reported for cattle of similar age (Jones and Allison, 2007), although an effect of medication was observed for RBC (Table 3).…”

“…In contrast, in the same study conducted by Brown et al (2015), as well as a study by Roberts et al (2015), it was found that oral meloxicam reduced peak Hp concentrations in calves castrated at weaning. Roberts et al (2018) observed that the reduction of Hp concentrations after oral meloxicam administration was only visible after surgical castration vs. band castration in weaned beef calves. The use of other NSAIDs (ketoprofen or carprofen) also mitigated inflammation after castration by decreasing Hp concentrations in 5.5-mo-old calves after knife and band methods (Early and Crowe, 2002;Pang et al, 2006).…”

Using advanced technologies to quantify beef cattle behavior1

“… White et al (2008) observed increased standing time in surgically castrated beef calves relative to precastration standing using two-axis accelerometers. In yearling-age feeder cattle, Roberts et al (2018) also reported increased standing time in surgically castrated bulls vs. band-castrated bulls or steer controls. Petherick et al (2014) reported a tendency for surgically castrated mature bulls (i.e.…”