Effect of flunixin meglumine on the amelioration of lameness in dairy steers with amphotericin B-induced transient synovitis-arthritis.

To characterize amphotericin B-induced lameness in cattle and to ascertain the analgesic effects of flunixin meglumine by use of multimodal assessment. 10 healthy Holstein steers free from musculoskeletal disease. Steers were randomly allocated to a treatment or negative control group. Amphotericin B was injected into the distal interphalangeal joint of the lateral claw of the left hind limb of all steers. Treatment steers received flunixin meglumine at the time of synovitis-arthritis induction and at 12 hours after induction. Control steers received no medication. Multimodal analysis included vital parameters, visual lameness score, behavioral monitoring with accelerometers, pressure mat analysis, and plasma cortisol determination before and after induction. Data were analyzed by use of linear mixed models with treatment and time designated as fixed effects, accounting for repeated measures on individual calves. Amphotericin B injection induced moderate, transient lameness. Control steers were more than twice as likely to be lame as treatment steers (mean ± SD lameness score, 92.2 ± 8.1 % vs 40.7 ± 2.5%). Treatment steers placed significantly greater force and contact area on the affected foot and greater force, impulse, and contact area on the paired claw, compared with control steers. Furthermore, treatment steers spent considerably less time in recumbency than controls. Amphotericin B successfully induced synovitis-arthritis in dairy steers that was transient in nature. Flunixin meglumine was efficacious in providing analgesia for these steers.