Indicators of Horse Welfare: State-of-the-Art

SIMPLE SUMMARY: Scientific interest in animal welfare was initially driven by popular emotional, ethics and political concerns. It has now become an important societal question and all the stakeholders agree on the necessity to rely on unambiguous scientific evidence for evaluation and making decisions. Animal welfare is defined as a chronic state reflecting an animal’s subjective perception of its situation indicated by behavioural, postural and physiological parameters. Because of their multiple statuses (as farm, leisure, sport or pet animals), horses experience a large variety of more or less adequate environmental conditions that present risks of impairing their welfare. The aim of this review is to disentangle welfare parameters and to differentiate reliable animal-based indicators of horses’ welfare from potential signals of acute sickness, discomfort, temporary states of pain, stress or emotion that are not based on popular beliefs in order to provide the equine industry with appropriate guidelines and recommendations. ABSTRACT: Animal welfare is defined as a chronic state reflecting an individual’s subjective perception of its situation. Because it is possible to be in a good welfare state and nevertheless experience acute fear or pain, and conversely, short-term positive emotions can be experienced during impaired welfare states, welfare as a chronic state has to be clearly distinguished from temporary states related to emotions, pain or stress. The evaluation of non-verbal individuals’ welfare state, particularly in interspecific situations, is a real challenge that necessarily implies animal-based measures and requires multidisciplinary scientifically validated measures. In the last decade, studies investigating horses’ welfare flourished together with new measures that were not always scientifically tested before being used. At a time were legal decisions are made on animal welfare, it is crucial to rely on reliable welfare indicators in order to prevent false evaluation. The aim of this review is to identify the scientifically tested and reliable indicators of horses’ welfare (e.g., body lesions, apathy, aggressiveness, stereotypic behaviours) from signals of temporary states related to acute pain emotions or stress and from popular beliefs, in order to give the scientific community and the horse industry accurate evaluation tools.