Assessment of the Impact of Locomotion on Animal Welfare

Locomotion is an important element of the animal's activity. It may take various states as regards gait and speed. Moreover, it supports all main behavioural functions in that locomotion enables the animal to act properly, in space and time, serving its different needs. For this reason impaired locomotion is an important threat to survival in free living animals, and probably perceived as such in all animals, including the domesticated species. The impact on welfare in farm animals should be considered in relation to this multifunctional nature of locomotion. But then the question arises as to how to assess the impact of impaired locomotion in proportion to other conditions affecting the animal? We propose to follow the decision support model for integrated welfare assessment developed by Bracke et al. 2002a. Fundamentally, welfare is assessed from the state of the biological needs of the animal. This welfare definition provides transparency and allows scientific verification. A list of biological needs has been worked out for sows, but analogous lists are easily made for other species. The model allows systematic weighting of the consequences of impaired locomotion in the various biological functions such as foraging behaviour, body care and safety. The model allows not only an assessment of impairment due to lameness, but also of the consequences of environmental restraints as inconvenient floors.