Abstract: 'Rollkur' or 'overbending' is the low and deep riding of a dressage horse during training or warming up. Lately, this technique has been criticized, and not necessarily objectively, on welfare grounds. To be able to evaluate these criticisms, more needs to be known about the workload and stress of horses being ridden 'rollkur'. The aim of the present study was to compare the workload of eight riding-school horses when being ridden deep and round with a draw rein ('rollkur') and when being ridden in a natural frame with only light rein contact ('free'). Workload (as measured by heart rate and blood lactate concentration) was slightly higher when horses were ridden 'rollkur' than when they were ridden 'free'. There were no differences in packed cell volume, or glucose and cortisol concentrations. No signs of uneasiness or stress could be determined when the horses were ridden 'rollkur'. Subjectively, all horses improved their way of moving during 'rollkur' and were more responsive to their rider.

Abstract: A multitude of endocrine mechanisms are involved in coping with challenges. Glucocorticoids, secreted by the adrenal glands, are in the front line of the battle to overcome stressful situations. They are usually measured in plasma samples as parameters of adrenal activity and thus of disturbance. Unfortunately, collecting blood samples itself can disturb an animal. Thus, non-invasive methods for the determination of glucocorticoids or their metabolites have become increasingly popular. The pros and cons of various non-invasive sample materials (saliva, excreta, milk, hair/feathers and eggs) for glucocorticoid determination are given. Above all, faecal samples offer the
advantage that they can be collected easily. In faecal samples, circulating hormone levels are integrated over a certain period of time and represent the cumulative secretion of hormones. Thus, the levels are less affected by short fluctuations or the pulse-like nature of hormone secretion. However, using this technique to assess an animal’s adrenocortical activity is not especially simple. Whether frequent sampling is necessary or single samples will suffice depends upon the study’s aim (whether one is examining the impact of acute or chronic stressors). Background knowledge of the metabolism and excretion of cortisol/corticosterone metabolites is required and a careful validation for each species and sex investigated is obligatory. The present review also addresses analytical issues regarding sample storage, extraction procedures and immunoassays and includes a comprehensive list of published studies (up to 2011) describing the use of such methods in farmed animals. Applied properly, non-invasive techniques to monitor glucocorticoid metabolites in faecal samples of various species are a useful tool for welfare assessment, especially as they are easily applied at farm or group level.

Abstract: A study carried out in four multi-male groups of captive dama gazelle (Gazella dama mhorr) characterized the social rank order of males and possible enclosure effects on aggression rate. A strong relationship between rank and age was found. The results also showed that dominant individuals in the two smallest enclosures were more aggressive than their herdmates, suggesting a more stressful environment, which might precipitate unstable or challenged hierarchies when the animals live in a more restricted enclosure. Subordinate males performed submissive responses at a higher frequency, irrespective of the size of the enclosure. The frequency of interactions between the gazelles, on the other hand, was affected by enclosure size, since high-ranking males showed higher values than low-ranking males in the two smallest enclosures. Frequencies of aggressive acts, retreats, and related interactions were similar in all the herds. Implications for the management of the species in captivity are discussed. Zoo Biol 19:121–129, 2000. © 2000 Wiley-Liss, Inc.

Abstract: Abstract Stress is a generic concept describing the body's reaction to external stimuli, including both physiological and psychological factors. Therefore, by definition, the assessment of psychological stress in the exercising horse encompasses the problem of teasing apart the psychological and physiological factors both of which result in stress responses. The present study reviews the existing literature on various measures of stress taken specifically in the context of equitation science. Particular attention has been paid to short-term effects, and commonly used measurements of short-term stress include heart rate, a number of heart rate variability parameters, blood or saliva cortisol levels, eye temperature, and various behaviour parameters including in particular behaviour patterns presumably indicative of conflict with the rider's/trainer's aids. Inspection of the individual studies' results revealed that disagreement between these different measures of stress is commonplace. For physiological parameters, the largest proportion of agreement (i.e. both parameters simultaneously indicated either higher, insignificant or lower stress compared to a control treatment) was found for heart rate and heart rate variability parameters, while generally limited agreement was found for cortisol. It appears that cortisol levels may not be particularly useful for assessing/assessment of the valence of a situation in the exercising horse as cortisol levels are predominantly linked to activation and exercise levels. Although heart rate variability parameters reflect in theory more closely sympathovagal balance compared to cortisol levels, great care has to be taken regarding the use of appropriate time-frames, appropriate raw data correction methods as well as the use of appropriate equipment. In spite of its wide-spread and apparently successful use, popular equipment may in fact not be accurate enough under field conditions. Eye temperature is another promising parameter for assessment of psychological stress, but the technique is likewise susceptible to application errors. Given the high susceptibility of physiological parameters to errors at various experimental stages, behavioural rather than physiological parameters may in fact provide more accurate measures of valence when conducting experiments in the exercising horse. Behavioural parameters that appear to be particularly practical in assessing stress in ridden horses' behaviour are associated with frequencies of behaviour indicative of conflict. However, while increased frequencies of are a good indicator of stress, the absence of conflict behaviour does not provide proof of the absence of stress due to the possible occurrence of conditions such as Learned Helplessness. In future studies, the above issues should be taken into consideration when designing experiments to assess psychological stress in ridden horses.