The impact of meloxicam on postsurgical stress associated with cautery dehorning

Abstract

The objectives were to determine the duration of the stress response associated with cautery dehorning and to assess the effectiveness of the nonsteroidal anti-inflammatory drug meloxicam (Metacam, 20 mg/mL solution for injection) for reducing that response. Sixty Holstein heifer calves were blocked by age and randomly assigned to receive an i.m. injection of meloxicam or a placebo (0.5 mg/kg). All calves were given a lidocaine cornual nerve block delivered 5 mL per side 10 min before dehorning. To establish baseline values, calves were sham dehorned 24 h before actual dehorning. Blood samples were taken via indwelling jugular catheters at 0, 0.5, 1, 1.5, 2, 4, 6, and 24 h after the procedure. Heart and respiratory rates were also taken at these times. Data were analyzed using PROC MIXED in SAS. Analysis of covariance was employed to assess the difference between sham and dehorning at each time period. Dehorning was associated with elevated serum cortisol (d -1: 33.9 +/- 1.26; d 0: 46.2 +/- 2.33 nmol/L) and heart rate (d -1: 108 +/- 1.8; d 0: 109.4 +/- 2.4 beats per minute) in both groups for 24 h, and elevated respiratory rate (sham: 42.2 +/- 1.95 vs. dehorning: 45.1 +/- 2.19 respirations per minute) in both groups for 6 h. A treatment x time interaction was found for cortisol, with meloxicam calves having lower serum cortisol than controls until 6 h after dehorning (meloxicam: 49.7 +/- 4.37 vs. control: 63.0 +/- 6.94 nmol/L). There was no difference between the treatment groups at 24 h (meloxicam: 35.2 +/- 2.74 and control: 34.8 +/- 3.64 nmol/L of cortisol). Overall, the changes in heart rates (increase meloxicam: 3.74 +/- 0.96 vs. control: 4.70 +/- 1.87) and respiratory rates (increase meloxicam: 2 +/- 0.1 vs. control: 4 +/- 0.2) were greater in the control group compared with the meloxicam group. These results indicate that meloxicam reduced the physiological stress response to dehorning.

Effect of oral meloxicam on health and performance of beef steers relative to bulls castrated on arrival at the feedlot1

“…Recently, meloxicam was approved in Canada as an aid in improving appetite and BW gains when administered at the onset of diarrhea and for relief of pain after disbudding of horn buds in calves less than 3 mo of age. Heinrich et al (2009) demonstrated that 0.5 mg of meloxicam/kg intramuscularly combined with a cornual nerve block reduced serum cortisol response longer compared with calves receiving only local anesthesia before cautery dehorning. This suggests that meloxicam may mitigate pain and distress associated with painful procedures such as castration similar to what has been reported after ketoprofen administration (Earley and Crowe, 2002).…”

Effect of previous handling experiences on responses of dairy calves to routine husbandry procedures

“…Heinrich et al (2009) also reported similar increases in RR following disbudding of calves with a local anaesthetic. The HR response in the present study was similar to the levels reported in other studies (Schwartzkopf-Genswein et al, 2005;Stewart et al, 2008;Heinrich et al, 2009;Stewart et al, 200) and was lower than the increase found in calves disbudded without pain relief.…”

“…Heinrich et al (2009) also reported similar increases in RR following disbudding of calves with a local anaesthetic. The HR response in the present study was similar to the levels reported in other studies (Schwartzkopf-Genswein et al, 2005;Stewart et al, 2008;Heinrich et al, 2009;Stewart et al, 200) and was lower than the increase found in calves disbudded without pain relief. There are no previous studies to compare the responses to ear-tagging; however, owing to the shorter duration and relatively little tissue damage, it is likely that ear-tagging is less painful than disbudding and this is supported by the greater behavioural and physiological response to disbudding than ear-tagging in the present study.…”

“…Administration of a local anaesthetic before disbudding markedly reduces, but does not completely eliminate, the behavioural and physiological responses of calves indicative of pain (Stafford and Mellor, 2005;Stewart et al, 2008). Cortisol concentration, HR, respiration rate (RR) and changes in behaviours indicative of pain, which have been shown previously to increase in response to disbudding (Stafford and Mellor, 2005;Heinrich et al, 2009;Stewart et al, 2009), were measured in the present study. We predicted that calves handled positively in early life would respond less to ear-tagging and disbudding than those handled previously in a negative manner and that overall the responses would be greater to disbudding than to ear-tagging.…”

“…This can be practically difficult to achieve; incomplete or partial effectiveness of analgesia can result from incorrect placement of the local anaesthetic due to operator variability and individual differences in the neural topography of the horn bud area. However, to completely alleviate the pain caused by disbudding, it is necessary to use a combination of a local anaesthetic and a non-steroidal anti-inflammatory agent (Faulkner and Weary, 2000;Stafford and Mellor, 2005;Heinrich et al, 2009;Stewart et al, 2009).…”