Actual lameness scores: Do more categories = Better data?

Objective

Locomotion scoring is commonly used to score gait, but there is limited agreement as to what systems are best or how valuable actual scores are. Unlike in cattle, there are no well-developed, well-established gait scoring systems in goats. One recent paper suggested that the lack of a category for uneven gait was a failing in most goat locomotion score systems (creating a 5-point system from a four point-system with three categories for lame goats). The aim of this paper is to use data from locomotion scoring on 4 commercial goat farms to assess whether this conclusion is correct and to reflect on the importance of using actual scores rather than simple lame/not lame dichotomies.

Materials and methods

We adapted a four-point scoring system used for cattle (AHDB/DairyNZ lameness score), which has two categories for lame cows and also a category for imperfect gait. Locomotion scoring was then attempted on four dairy goat farms. Goats on each farm were scored walking back to their pens after milking, with the observer being positioned in a vehicle approximately 10 metres away from the walking goats to reduce distraction. This ensured that the maximum number of goats were scored on each occasion and that they were all scored walking on a hard surface. [...]