A randomised factorial design clinical trial to investigate the impact of parenteral long acting oxytetracycline, foot trimming and flunixine meglumine on time to recovery from lameness and foot lesions in sheep lame with footrot

Abstract

Background: Internationally, foot trimming is used by most farmers and parenteral antibacterials by some, to treat sheep with footrot. Non steroidal anti-inflammatory drugs (NSAID) are sometimes used. No clinical trials have compared these treatments. Objectives: To investigate the above treatments on time to recovery from lameness and foot 5 lesions in sheep with footrot. Animals: 53 sheep with footrot on a commercial farm in England. Methods: In a randomised factorial design, the sheep were allocated to treatment groups. The 8 treatments were oxytetracycline spray to all sheep (positive control) and one or more of: parenteral administration of long acting oxytetracycline, flunixine meglumine and foot trimming on day 1 or day 6 of diagnosis. Follow-up was for 15 days. Time to recovery from lameness and lesions was investigated with discrete- time survival models. Results: There was significant association (p<0.05) between recovery from lameness and lesions. Sheep receiving antibacterials parenterally recovered faster from lameness (odds ratio (OR): 4.92 (1.20-20.10)) and lesions (OR: 5.11 (1.16-22.4)) than positive controls whereas sheep foot trimmed on day 1 (lameness- OR: 0.05 (0.005-0.51); lesions- OR: 0.06 (0.008-0.45)) or day 6 of diagnosis (lameness-OR: 0.07 (0.01-0.72); lesions- OR: 0.07 (0.01-0.56)) recovered slowly than positive controls. NSAID had no significant effect on recovery. Conclusions and Clinical Importance: If foot trimming on day 1 or 6 of diagnosis was stopped and parenteral antibacterials were used, then over 1 million sheep/annum lame with footrot in the UK, would recover more rapidly with benefits to productivity. Globally, this figure would be 21 much higher