RESUMO
The objective was to evaluate the analgesic efficacy of pre- and postoperative administration of meloxicam on the postsurgical convalescence period of lame dairy cows undergoing resection of the coffin joint. In a blinded, placebo-controlled, explorative clinical trial, 19 lame German Holstein-Friesian cows weighing 536 ± 98 kg (mean ± SD) and aged 5.7 ± 2.8 yr were included. All cows suffered from unilateral lameness due to septic arthritis of the coffin joint. Lame cows were randomly allocated to either the meloxicam group (n=9) or the control group (n=10) and received an intravenous injection of meloxicam (0.5mg/kg of BW) or an equal volume of saline immediately before surgery (d 0) and once daily from d 1 to 4. All cows received a retrograde intravenous local anesthesia (20 mL of procaine 2%) before the surgical intervention. Heart rate, respiratory rate, body temperature, plasma concentrations of cortisol, as well as production parameters (milk yield and feed intake) were evaluated from d 0 to 7. The gait of the animals was assessed daily by lameness scores and by monitoring the cows' activity by means of pedometers attached to both hind legs. Possible adverse effects on abomasal mucosal integrity were monitored by fecal occult blood tests and blood cell counts from d 0 to 7 and on d 14. Under meloxicam treatment plasma cortisol levels, lameness scores, and body temperature were significantly reduced compared with controls. While being treated with meloxicam, the time cows were standing per day was significantly longer compared with controls. In the healthy limb significantly more steps were registered in meloxicam-treated cows than in controls. Feed intake and milk yield were not significantly affected by meloxicam. No group differences were found in number of positive tests for fecal occult blood or blood cell counts. In conclusion, repeated meloxicam application demonstrated effective analgesia in the postsurgical period after resection of septically infected coffin joints in dairy cows without indications of evoking adverse effects on abomasal integrity.