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• Effects of meloxicam on chronic indicators of pain after castration. • Cow-calf proximity and home range as novel indicators of pain post-castration. • Knife and banded calves experienced more acute and chronic pain, respectively. • Meloxicam did not reduce indicators of pain at the time-points assessed. • Proximity and home range have the potential to be used as indicators of pain. One hundred and thirty-one 2 mo. old pasture housed Angus cross bull calves were evaluated for 62 d over two years (Year 1: n = 69, 134.1 ± 20.37 kg BW; Year 2: n = 62, 118.1 ± 15.49 kg BW) to determine 1) the effects of a subcutaneous (s.c) injection of meloxicam on indicators of long term pain after castration and 2) the potential use of cow-calf proximity and home range as indicators of pain. Calves were randomly assigned to treatments using a 3 × 2 factorial design including castration - sham (CT; n = 47), band (BA; n = 46) or knife (KN; n = 38) castration and medication – s.c. meloxicam (M; n = 66) or s.c. lactated ringers solution (NM; n = 65). Measurements included performance, scrotal temperature, swelling (WS) and healing (WH) scores, and pain sensitivity, collected on d -1, 6, 13, 20, 34, 48, and 62 post-castration. Suckling, lying, standing and walking duration, and head-turning, lesion-licking, foot-stamping and tail-flick frequencies were collected immediately following and up to 2-d after castration. Cow-calf proximity and home range were obtained from d 0 to 2 and from d 14 to 16. With the exception of suckling, no medication (P > 0.05) effects were found. Greater (P < 0.05) pain sensitivity was observed in KN from d 6 to 34 and on d 62, and in BA from d 6 to 62 compared to CT calves. Knife calves showed an earlier (d 20) absence of inflammatory responses (WS; P < 0.05) than BA (d 34) and overall, KN calves had greater (P < 0.05) standing, walking, and head turning than BA and CT. Knife and BA had greater (P < 0.05) foot stamping than CT for the first 2 h post-castration, but KN exhibited greater (P < 0.05) frequencies between 9 and 11 h (d 0) compared to BA and CT, and had greater (P < 0.05) tail flicks from d 0 to 2 than CT. Banded calves were closer to their dams on d 15 while KN calves and their dams had a reduced home range on d 0 than CT cow-calf pairs. Although meloxicam did not reduce indicators of pain (with exception of suckling behavior), our results suggest that knife castration causes greater acute pain, while band castration resulted in greater chronic-pain. Cow-calf proximity and home range have some potential to be used as pain indicators post-castration. [ABSTRACT FROM AUTHOR]

• Knife castrated calves experienced more acute pain than band castrated calves. • Combination of flunixin plus lidocaine reduced indicators of pain in castrated calves. • Combination of medication mitigated pain in knife and band castrated calves. One hundred and seventy-four Angus bull calves (248 ± 27.1 kg of body weight (BW), 6-mo-old) were used in a 71 d study to assess the efficacy of the combination of flunixin meglumine and lidocaine in mitigating pain associated with band and knife castration. The experiment consisted of a 3 × 2 factorial design that included castration method -sham (C), band (B) or knife (K) ; and medication – lidocaine (scrotal ring block 30 mL, 2% HCl lidocaine) and flunixin meglumine (single s.c. dose of 2.2 mg/kg BW) (M), or saline solution (NM). Animals were weighed on d 0 and weekly until d 71 (final BW) post-castration to obtain ADG. Physiological indicators included salivary cortisol collected on d 0 (30, 60, 120 and 240 min), d 2, 8, and weekly until d 48 post-castration; scrotal and eye temperature assessed on d 1, 2, 6, 8, and weekly until d 36 post-castration; fecal samples for E. coli collected on d 0, 2, 6, 8, and 22 post-castration. Behavioral measures included stride length on d 0, 8, and weekly until d 36, visual analog scale (VAS) evaluated during castration, and feeding behavior collected daily from d 0 to d 71 post-castration. Final BW and ADG were greater (P < 0.05) in C than B and K castrated calves. Salivary cortisol concentrations were greater (P < 0.05) in B and K calves than C calves up to 4-h post-castration, and remained greater in K calves up to 48-h post-castration, while concentrations were lower (P = 0.01) in M than NM calves. Fecal E. coli varied daily (P = 0.01) however, there was no obvious pattern over time. Scrotal temperature was greatest (P < 0.05) in K, intermediate in C and lowest in B calves, except at 30 min, and 22 and 36 d post-castration where they did not differ from C calves. Eye temperature was greater (P < 0.05) in B and K than C calves on d 2 and 8 post-castration. No differences (P > 0.10) were observed for stride length. The VAS scores were greater (P = 0.01) in K than C and B calves, while NM had greater scores (P < 0.01) than M calves. Dry matter intake and meal size were greater (P = 0.05) in M than NM calves. Meal duration was greater (P = 0.01) in B and C than K calves on d 0, while K calves had greater (P < 0.01) meal duration than C calves 1 and 2-wk post-castration. Overall, the combination of flunixin meglumine and lidocaine reduced physiological and behavioral indicators of pain, suggesting that their combined use was effective at mitigating pain associated with band and knife castration. [ABSTRACT FROM AUTHOR]