Abstract: Tbourida is a traditional Moroccan equestrian sport in which 15 horses gallop 200 m in a line while riders fire into the sky with muskets. The stop is the finale and representative demands of this equestrian event. Such particular sudden stop after a fast gallop requires a hyperextension of the metacarpophalangeal joint. Indeed, it is well known that Tbourida show predisposes horses to different injuries of the hard and soft tissues of the distal forelimbs. Yet, there is a paucity of research that examined such lesions. The aim of the present study was to investigate for the first time the type and the prevalence of osteoarticular findings in the distal forelimbs of Tbourida horses using radiographic images. The study was conducted on 127 Tbourida horses aged between 2.5 and 15 years old with 6-year-old horses being the most affected. Data analysis showed that 93,7% of horses exhibit degenerative joint lesions of the fetlock, 86,6% showed ossification of the ungual cartilage, 78,7% had enthesophytes associated with the deep digital flexor tendons, 81,1% had enthesophytes associated with the suspensory ligament branches, and 19,6% showed a particular exostosis on the first phalanx. This large number of lesions reflects how this sport is difficult for horses and also argues that animals are suffering from a lack of welfare and care in their husbandry management.

Abstract: Most horses are trained by negative reinforcement. Currently, however, no standardised test for evaluating horses' negative reinforcement learning ability is available. The aim of this study was to develop an objective test to investigate negative reinforcement learning in horses. Twenty-four Icelandic horses (3 years old) were included in this study. The horses were tested in a pressure-release task on three separate days with 10, 7 and 5 trials on each side, respectively. Each trial consisted of pressure being applied on the hindquarter with an algometer. The force of the pressure was increased until the horse moved laterally away from the point of pressure. There was a significant decrease in required force over trials on the first test day (P<0.001), but not the second and third day. The intercepts on days 2 and 3 differed significantly from day 1 (P<0.001), but not each other. Significantly stronger force was required on the right side compared to the left (P<0.001), but there was no difference between first and second side tested (P=0.56). Individual performance was evaluated by median-force and the change in force over trials on the first test day. These two measures may explain different characteristics of negative reinforcement learning. In conclusion, this study presents a novel, standardised test for evaluating negative reinforcement learning ability in horses.

Abstract: Every animal species has particular environmental requirements that are essential for its welfare, and when these so-called “basic needs” are not fulfilled, the animals suffer. The basic needs of horses have been claimed to be social contact, social companionship, free movement and access to roughage. To assess whether horses suffer when one or more of the four proposed basic needs are restricted, we examined several studies (n = 38) that reported behavioural and physiological reactions to these restrictions. We assigned the studies according to the four types of responses investigated: (a) Stress, (b) Active, (c) Passive, and (d) Abnormal Behaviour. Furthermore, the number of studies indicating that horses reacted to the restrictions were compared with the number of studies reporting no reaction. The limited number of studies available on single management restrictions did not allow conclusions to be drawn on the effect of each restriction separately, especially in the case of social companionship. However, when combinations of social contact, free movement and access to roughage were restricted, many of the horses had developed responses consistent with suffering. Passive Responses, indicating acute suffering, and Abnormal Behaviour, indicating suffering currently or at some time in the past, were especially clearly demonstrated. This provides further evidence of the usefulness of assessing behavioural parameters in combination with physiological measurements when evaluating horse welfare. This meta-analysis of the literature confirms that it is justified to claim that social contact, free movement and access to roughage are basic needs in horses.

Abstract: In recent years, Przewalski’s horses have been increasingly kept in semi-reserves. However,there areonly few studies ontheir behaviour and their ability to adaptto management interventions.In the main part of my dissertation, I focus on investigatingthe animals’ behaviour in different semi-reserves with varyinghabitats and living spaces. In addition, I investigate the horses’ behaviour during various management interventionsand analysetheensuing changes instress levels. Another aspect of my dissertation is the studyof social behaviour inPrzewalski’s horses. I investigate theparameters that should be used to demonstrate social bonds between individualsandassess whichdata provide the most meaningful results.In the commentary tochapter 1,several studies investigatingsocial bonds in horsesare discussed. Comparing the various studies, it is strikingthat no homogeneous analyses orevaluation criteria exist. While some authors only considersocial grooming, others include data onthe spatial proximity of the individuals in their evaluations, and various definitionsof proximity can also be found in the literature. Additionally, someauthors use friendly approaches between individuals asa furtherparameter wheninvestigating the social bonds.Continuing with this theme, in chapter 2I investigate the social behaviour of the horses and compare various analysis methods. I show that proactive behaviour, such as friendly approaches, is a good alternative to spatial proximity when investigating social bonds between group members, andis also useful for expanding the often very small data sets of mutual grooming in horses. Comparing Przewalski’s horses with wild living horses, I found no significant differences in the social behavior and the frequency of social interactions, regardlessof group size, group composition, habitat, and individual parameters such as age and gender.Inchapter 3,I investigate the behaviour of a Przewalski’s horse group when exploring a new area of their enclosure. Their behaviour changed, showing less resting and more feeding. Furthermore, the animals maintained greater distances from each other, and the alpha male, instead of herding the group from behind, led the group around the new area and walked in front of the other group members. Moreover, he showed a substantial increase in stress level during the first day.A general comparison of the behaviour of the Przewalski’s horses in different semi-reserves is provided in chapter 4. In it, the habitat choice of the animals and their reactions to various management interventions are investigated. It is shown that Przewalski’s horses prefer open grassland to dense woods, although keeping Przewalski’s horses in a pine forest does not influence the animals’ stress level. In contrast to habitat, food range, and changes in the group composition, which do not appear to change stress levels, individual factors, such as the hierarchy, influence the glucocorticoid level of the animals significantly. The largest increases in stress hormones were demonstrated when the horses were temporarily confined in smaller areas.The importance of the available space is also discussed in chapter 5, where it is shown that horses show less aggressive behaviour when more space is provided. In contrast, the husbandry system does not influence the animals’ aggression, but the way of feeding can additionally reduce agonistic behaviour, for example if food is offered ad libitum.In summary, the results of this study provide indications for the optimization of keeping Przewalski’s horses in semi-reserves. The animals can adapt themselves to the environment and thrive in habitats which do not correspond to their original steppe-like home. Nevertheless, the semi-reserves should provide sufficient grassland, as the horses prefer this type of habitat. General speaking, any types of habitat can only offer a suitable living space if the food range is sufficient for the number of horses. Otherwise, and especially during could winter months, supplementary feeding is necessary according to the body condition of the animals. This is particularly important for older, weakened, or very young animals, which are still adapting to life in the semi-reserve. Without sufficient food, stress hormones can increase and negatively influence the well-being of the horses. The same is true for management interventions: restricting the animals to small enclosures, for example, can adversely affect the horses’ well-being and should be only done if absolutely necessary. Targetedbehaviour observations allow the animals that have a special meaning for the group to be identified, and these should not be taken out of the group unless it is unavoidable, as young and unexperienced horses orientate themselves on those animals. This is especially true for the alpha male in a bachelor group, as these groups are often composed of young horses and the alpha-male provides the necessary stability and experience. Social bonds between individuals can be investigated by observing friendly and proactive behaviour, and social grooming and friendly approaches yield suitable data for such analysis.