Measuring the response to therapeutic foot trimming in dairy cows with fortnightly lameness scoring.

Lameness scoring (0-3) was carried out on four UK dairy farms during the housing period over three consecutive years (2010-2012). At the start of the study cows were matched by parity and stage of lactation and randomly allocated into a treatment (TX) and a control (CX) group. Cows were enrolled when two sound scores (0 or 1) were followed by a lame score (2). Farmers were immediately notified of score 3 cows, which were then excluded from the study, irrespective of whether they were in treatment or control groups. The animals in the TX group received treatment 3-48 h after being scored lame. Farmers remained blind to the treatment group. Throughout the study the participating farmers continued to identify and treat lame cows according to their usual approaches, this included treating animals in the CX or TX group if they so chose. The fortnightly lameness scoring and treatment of the TX group resulted in higher cure rates at each scoring session following treatment when compared with the CX group (P < 0.001). Two weeks after inclusion, 78% (SE  ±  3.2) of TX cows were sound, compared with 66% (SE  ±  3.1) of CX cows. At 18  weeks following initial recruitment this had fallen to 41% (SE  ±  6.3) (TX) and 13% (SE  ±  4.7) (CX). The percentage of total scores which were sound scores in the TX and CX groups following inclusion in the trial was 81% and 66.1%, respectively (P < 0.001). The main lesions found on treatment in the TX group were sole haemorrhage (41% of cases) and digital dermatitis (33%). Severe lesions (sole ulcers and toe necrosis) were only found in 6.6% of cases. In the treated CX animals the percentage of severe lesions was 14%.