Equine on-farm welfare assessment: a review of animal-based indicators

The adaptability of horses and donkeys to different types of activity has seen the European equine industry become an important economic sector, giving rise to increasing concern regarding equine welfare. As part of the AWIN (Animal Welfare Indicators) project, this review focuses on scientific literature to find potential animal-based welfare indicators - the initial step in developing a valid, reliable and feasible on-farm welfare assessment protocol for equines. Forty-nine indicators were considered and classified in accordance with the four Principles and twelve Criteria developed by Welfare Quality (R). Only practical indicators specifically for on-farm use were included, those requiring the use of specific instruments or laboratory analysis were excluded. Academic scientists, partners and collaborators of the AWIN project, discussed and agreed on validity, reliability, on-farm feasibility and acceptance by farmers for each indicator. Some aspects of equine welfare have been thoroughly investigated and appear to have indicators ready for on-farm use (eg 'absence of prolonged hunger', 'absence of injuries and diseases'). On the other hand, a lack of animal-based measures were identified for other Criteria such as 'absence of pain' and 'positive emotional state'. Ongoing research within the AWIN project has begun exploring some of the aforementioned Criteria - these preliminary results of promising indicators have been included (eg Horse Grimace Scale and Qualitative Behaviour Assessment). Further research should address the validity and reliability of indicators, such as human-animal relationship tests and signs of cold stress. As well as for working equines, the development and application of a welfare assessment protocol could be the first step for enhancing on-farm equine welfare.