Effect of training on the inter-observer reliability of lameness scoring in dairy cattle

In the present study, the effect of training on inter-observer reliability was studied for a 5-category lameness scoring system used for routine on-farm surveys of welfare in dairy cattle. The inter-observer agreement between an experienced and an initially inexperienced observer was determined during an initial training phase and at specific time points in the course of data collection in 46 herds. During the training phase on three farms, inter-observer reliability increased to an acceptable level for both the 5-category gait scoring system and the distinction between lame and non-lame cows. The 4th testing after 17 on-farm visits revealed a considerable increase in inter-observer reliability which was further improved in the course of the on-farm visits. In conclusion, acceptable inter-observer agreement for differentiating between non-lame and lame cows was achieved after only a brief introduction. In order to obtain high inter-observer repeatability with the 5-category gait scoring system used in this study, (more) intensive training procedures are required.