Acute laminitis is a common equine disease characterized by intense foot pain, both acutely and chronically. The Obel grading system is the most widely accepted method for describing the severity of laminitis by equine practitioners, however this method requires movement (walk and trot) of the horse, causing further intense pain. The recently developed Horse Grimace Scale (HGS), a facial-expression-based pain coding system, may offer a more effective means of assessing the pain associated with acute laminitis. The aims of this study were: to investigate whether HGS can be usefully applied to assess pain associated with acute laminitis in horses at rest, and to examine if scoring HGS using videos produced similar results as those obtained from still images. Ten horses, referred as acute laminitis cases with no prior treatment, were included in the study. Each horse was assessed using the Obel and HGS (from images and videos) scales: at the admission (before any treatment) and at seven days after the initial evaluation and treatment. The results of this study suggest that HGS is a potentially effective method to assess pain associated with acute laminitis in horses at rest, as horses showing high HGS scores also exhibited higher Obel scores and veterinarians classified them in a more severe painful state. Furthermore, the inter-observer reliability of the HGS total score was good for both still images and video evaluation. There was no significant difference in HGS total scores between the still images and videos, suggesting that there is a possibility of applying the HGS in clinical practice, by observing the horse for a short time. However, further validation studies are needed prior to applying the HGS in a clinical setting.
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®. 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.
The EU-funded Animal Welfare Indicators (AWIN) research project (2011-2015) aimed to improve animal welfare through the development of practical on-farm animal welfare assessment protocols. The present study describes the application of the AWIN approach to the development of a welfare assessment protocol for horses (Equus caballus). Its development required the following steps: (i) selection of potential welfare indicators; (ii) bridging gaps in knowledge; (iii) consulting stakeholders; and (iv) testing a prototype protocol on-farm. Compared to existing welfare assessment protocols for other species, the AWIN welfare assessment protocol for horses introduces a number of innovative aspects, such as implementation of a two-level strategy focused on improving on-farm feasibility and the use of electronic tools to achieve standardised data collection and so promote rapid outcomes. Further refinement to the AWIN welfare assessment protocol for horses is needed in order to firstly gather data from a larger reference population and, secondly, enhance the welfare assessment protocol with reference to different horse housing and husbandry conditions.