Qualitative categories for the interpretation of sheep welfare: a review
The aim of this paper is to discuss the relationship between qualitative categories of sheep welfare and associated quantitative behavioural observations. Most scientific studies rely on quantitative measures, however to interpret those measures in terms of an animal's experience of
welfare, the use of qualitative terminologies denoting various emotional states (eg fear, pain, distress) seems hard to avoid. This is especially so in cases where the same behavioural or physiological indicator could have different meanings for welfare; high levels of locomotion, for example,
could indicate fear, aggression, or both. To resolve such dilemmas, scientists often resort to judging an animal's most likely state through direct observation; indeed qualitative characterisations are often intertwined with reported quantitative results. This paper reviews frequently used
qualitative categories of sheep welfare and the behavioural context in which these categories are applied. Qualitative judgements of welfare tend to habitually be regarded as 'subjective', ie as anthropomorphic and unreliable; however from this review it appears that such judgements reflect
the overall demeanour of an animal's behaviour, and as such may provide a useful empirical basis for the investigation of emotional expression in sheep. Further development of a qualitative behavioural approach may provide a more complete picture of the expressive repertoire of sheep, and
enhance our understanding of ways in which these animals experience well-being or distress.