Abstract: The spontaneous behaviour and the apparent digestibility of dry matter and fibre and transit times of digesta were compared in four normal horses and four crib-biters. A technique was developed for measuring total gut transit times (TGTT) by using single-stool analysis of the passage of radio-opaque polyethylene markers. Longer TGTT were recorded in the crib-biters than in the normal horses but the orocaecal transit times did not differ. The crib-biters rested less than the normal horses.

Abstract: The lengthy association of humans with horses has established traditional equestrian techniques that have served military and transport needs well. Although effective, these techniques have by-passed the research findings of modern psychologists, who developed the fundamentals of learning theory. That said, the pools of equestrian debate are far from stagnant. The latest wave of horse whisperers has offered some refinements and some novel interpretations of the motivation of horses undergoing training. Additionally, the Federation Equestre Internationale (FEI) has introduced the concept of the 'happy equine athlete' and, in the light of the hyperflexion (Rollkur) debate, recently examined the possible effects of some novel dressage modalities on equine 'happiness'. However, many still question the welfare of the ridden horse since it is largely trained using negative reinforcement, has to respond to pressure-based signals and is seldom asked to work for positive rewards. Science holds tremendous promise for removing emotiveness from the horse-riding welfare debate by establishing how much rein tension is too much; how much contact is neutral; how contact can be measured; how discomfort can be measured; how pain can be measured; and how learned helplessness manifests in horses. These are some of the topics addressed by equitation science, an emerging discipline that combines learning theory, physics and ethology to examine the salience and efficacy of horse-training techniques.

Abstract: This article examines the recently completed equid ethogram and shows how analogues of social interactions between horses may occur in various human–horse interactions. It discusses how some specific horse–horse interactions have a corresponding horse–human interaction – some of which may be directly beneficial for the horse while others may be unusual or even abnormal. It also shows how correspondent behaviours sometimes become inappropriate because of their duration, consistency or context. One analogue is unlikely to hold true for all horse–human contexts, so when applying any model from horse–horse interactions to human–horse interactions, the limitations of the model may eclipse the intended outcome of the intervention. These limitations are especially likely when the horse is being ridden. Such analyses may help to determine the validity of extrapolating intra-specific interactions to the inter-specific setting, as is advocated by some popular horse-training methods, and highlight the subsequent limitations where humans play the role of the ‘alpha mare’ or leader in horse handling and training. This examination provides a constructive framework for further informed debate and empirical investigation of the critical features of successful intra-specific interactions.

Abstract: In ethical discussions, a cost-benefit analysis requires that welfare costs associated with an activity can be reliably estimated and balanced against the potential benefits of the activity to both humans and animals. The current study applies a meta-analysis to the peer-reviewed evidence for costs and benefits of hyperflexion of the neck in horses; a practice that has attracted enormous public and scientific scrutiny over the past 15 years. A literature review identified 55 studies dealing with horses’ head and neck postures. Fourty-two of these studies examined the impact of various postures on equine welfare, for example, by assessing behavior, physiological stress parameters, health or rider-horse interaction. Thirty-five studies examined the impact of various postures on gymnastics (e.g. kinematics, shifts in weight distribution, muscle activity, airway functioning or overall workload). For the meta-analysis a dataset containing information from each of the individual studies was created. Data included information such as type, degree, duration and circumstances of hyperflexion applied in that particular study as well as information on the horses (e.g., sport discipline, level of training, breed) and on the study design (e.g., size of study and experimental or epidemiological research design). The results of the study regarding the impact of hyperflexion on a) welfare and b) gymnastics were coded as positive (1), insignificant or contradictory (0) or negative (-1). The significant majority of studies (88%) concluded that a hyperflexed head and neck posture negatively impacts welfare. Just one study suggested welfare advantages of training in a hyperflexed head and neck posture. An analysis using a generalized linear mixed model to assess the influence of the above factors collated in the dataset revealed that none of these factors significantly influenced the probability of a study to detect negative welfare implications. Thus hyperflexing the neck appears to impair horses’ welfare regardless of, for example, the duration or the way of achieving hyperflexion. A concurrent assessment of the evidence for gymnastic benefits showed that approximately one quarter of studies conclude that there may be benefits, while another quarter of the studies conclude that hyperflexion has detrimental effects on gymnastics. Thus, on the costs-side there is a clear reduction in equine welfare and some undesirable gymnastic effects, as well as likely a compromised profile of the equestrian sports in public. Benefits, on the other hand, include some desirable gymnastic effects, and potentially increased control of the horse for the rider. On balance, it appears that the costs associated with hyperflexion exceed the potential benefits of the activity to both humans and horses.

Abstract: Dominance hierarchies in horses primarily influence priority access to limited resources of any kind, resulting in predictable contest outcomes that potentially minimize aggressive encounters and associated risk of injury. Levels of aggression in group-kept horses under domestic conditions have been reported to be higher than in their feral counterparts but can often be attributed to sub-optimal management. Horse owners often express concerns about the risk of injuries occurring in group-kept horses but these concerns have not been substantiated by empirical investigations. What has not yet been sufficiently addressed are human safety aspects related to approaching and handling group-kept horses. Given horses? natural tendency to synchronize activity to promote group cohesion, questions remain about how group dynamics influence human-horse interactions. Group dynamics influence a variety of management scenarios, ranging from taking a horse out of its social group to the prospect of humans mimicking the horse?s social system by taking a putative leadership role and seeking after an alpha position in the dominance hierarchy to achieve compliance. Yet, there is considerable debate about whether the roles horses attain in their social group are of any relevance in their reactions to humans. This article reviews the empirical data on social dynamics in horses, focusing on dominance and leadership theories and the merits of incorporating those concepts into the human-horse context. This will provide a constructive framework for informed debate and valuable guidance for owners managing group-kept horses and for optimizing human-horse interactions.