Abstract: Recent interest has focused on the advantage of intensively handling young foals as a means of producing more tractable horses, accustomed to humans and receptive to training. To date, the effect of this intensive handling, dubbed “imprint training” in the popular literature, has not been tested. The present study compares seven foals handled intensively as neonates with eight untreated controls. The handling protocol started from 2-8 h after birth and continued daily for a total of 5 days. The protocol consisted of a series of stimuli and experiences that were each repeated until the foal no longer resisted or reacted negatively. Subsequently, foals were tested before weaning, at 4 months of age. Results indicated that handled foals (HF) ranked higher than control foals (CF) in subjective ratings of calmness (*P<0.0117) and friendliness (*P<0.0001) and in several specific handling tasks (venipuncture *P<0.0220; placing in stock *P<0.0128). Although, in approach tests all foals but one allowed approach of a person to 4 m, significantly more HF approached the person than CF (P<0.0080). In stimulus tests, foals were presented specific stimuli to which they had been tested as neonates. Two of eight CF were too unruly and dangerous to test. Of foals that could be tested, CF required significantly more time to hook-up a heart rate monitor (**P<0.0055). Split-plot analysis indicated that HF had lower heart rates to initial left-sided stimuli, presented first, than CF (*P<0.0421). In response to right-sided stimuli, heart rate scores of CF were not significantly different from HF (P<0.2259), suggesting reduced reactivity over time due to a learning effect. Behavioral responses to specific stimuli did not differ between CF and HF, suggesting that neonatal handling has a general rather than specific effect on subsequent behavior. Cortisol concentrations were measured before and after testing and the difference calculated. All foals had higher post-testing levels than pre-testing levels. There was a significant difference between HF and CF, indicating greater reactivity among the CF (*P<0.050). In general, the results indicated that foals handled as neonates were more tractable and less reactive. Specific neonatal handling tasks, such as sticking a finger up the foal's nose or patting the bottom of the foot, seemed to have no beneficial effect on related tasks such as passing a nasogastric tube or tapping with a farrier's hammer at 4 months of age. Mechanisms for the observed effect of neonatal handling require further investigation.

Abstract: This series of studies investigated horses' ability to learn the concept of sameness under several different conditions. Before experimentation began, three horses were shaped to touch individually presented stimuli with their muzzles, and then to make two responses to two matching cards from an array of three. A modified version of the identity matching-to-sample (IMTS) procedure was used to present stimuli in a variety of configural arrangements on a barn wall (Experiment 1 and Experiment 2), and on a flat panel mounted to a barn door (Experiment 3). The task in each experiment was to select the two stimulus cards that were the same (either circles or Xs) and to avoid the nonmatching stimulus card (either a star or a square). In Experiment 1, the mean accuracy rate for selecting the matching alternatives was 74%. The horses' accuracy levels reached a mean level of 83% during Experiment 2, in which they received additional trials and an intermittent secondary reinforcement schedule. In Experiment 3, when the stimuli were moved further apart from each other within arrangements and were presented on a novel background, the mean accuracy rate was 73%. These data demonstrate that horses can learn complex discrimination problems involving the concept of sameness, and that they are able to generalize this learning to a novel stimulus presentation situation. These results also suggest that a relational discrimination test may be useful for assessing horses' learning ability and the level of training appropriate for individual horses.

Abstract: Rollkur, the usually coercively obtained hyperflexion of the horse's neck, is employed as a training method by some dressage riders; however, its use is controversial as it may cause discomfort and adversely affect the horse's welfare. The objectives of this study were to determine: (1) if horses showed differences in stress, discomfort and fear responses as measured by heart rate and behaviour when ridden in Rollkur (R) obtained by pressure on the reins compared to regular poll flexion (i.e. with the nose-line being at or just in front of the vertical; N), and (2) if they showed a preference between the two riding styles when given the choice. Fifteen riding horses were ridden 30 times through a Y-maze randomly alternating between sides. Riding through one arm of the Y-maze was always followed by a short round ridden in R, whereas riding through the other arm was followed by a short round ridden in N. Immediately after the conditioning phase, horses were again repeatedly ridden into the maze; however, riders left it to the horse to decide which arm of the maze to enter. During R, horses moved slower and showed more often behavioural signs of discomfort, such as tail-swishing, head-tossing or attempted bucks (P < 0.05), and 14 of the 15 horses chose significantly (P < 0.05) more often the maze-arm associated with N rather than R. Subsequently, eight of the horses were also subjected to two fear tests following a short ride in N as well as a ride in R. During R, horses tended to react stronger (P = 0.092) to the fear stimuli and to take longer (P = 0.087) to approach them. These findings indicate that a coercively obtained Rollkur position may be uncomfortable for horses and that it makes them more fearful and therefore potentially more dangerous to ride. Further studies need to assess horses' reaction to gradual training of Rollkur, as opposed to a coercively obtained hyperflexion, in order to decide whether the practice should be banned.

Abstract: From the viewpoint of experimental psychology, there are two problems with our current knowledge of equine perception. The first is that the behavioral and neurophysiological research in this area has enormous gaps, reflecting that this animal is not a convenient laboratory subject. The second is that the horse, having been a close companion to humans for many millennia, entrenched anecdotal wisdom is often hard to separate from scientific fact. Therefore, any summary at present of equine perception has to be provisional. The horse appears to have developed a visual system particularly sensitive to dim light and movement, it may or may not have a weak form of color vision in part of the retina, it has little binocular overlap, and its best acuity is limited to a restricted horizontal band which is aimed primarily by head/neck movements. However, the total field of view is very large. Overall, as would be expected for a prey animal, horse vision appears to have evolved more for detection of predator approach from any angle than for accurate visual identification of stationary objects, especially those seen at a distance. It is likely that, as for most mammals except the primates, horses rely more heavily on their other senses for forming a view of their world. Equine high-frequency hearing extends far above that of humans, but horses may be less able to localize the point of origin of brief sounds. The horse's capacity for chemoreception and its reliance on chemical information for identification may more closely resemble that of the dog than of the human. Its tactile sensitivity is high, and the ability of its brain and body to regulate pain perception appears to be similar to that found in other mammals. There is room for a great deal of future research in both the area of equine perception and sensory-based cognition, but for the present time persons interacting with this animal should be made aware of the importance of the sounds they make, the movements of their bodies, the way they touch the animal, and the odors they emit or carry on their clothing.

Abstract: Horses are well able to form classical and instrumental associations and so the focus of much recent research has been on the stimulus control of instrumental learning. Horses appear to discriminate using spatial cues more easily than other stimulus features, as indicated both by the speed of initial task acquisition and by the extent to which acquired discriminations can be reversed. Phenomena associated with discrimination learning in laboratory animals, including generalisation and peak shift, have been demonstrated in horses. However, the ability of horses to classify stimuli into categories is more controversial. Although there is some evidence that horses may be able to form categories based on similarities in the physical appearance of different stimuli, there is currently no evidence that they are able to develop abstract concepts. Their performance on social learning tasks has also been poor. Few correlations are observed between the learning ability of individual horses on different tasks, suggesting that it may not be possible to classify individual horses as `good' or `poor' learners. Better learning performance by horses that are naturally calm is probably due to reduced interference in the learning process. Correct handling procedures can lower reactivity levels in horses, and may facilitate learning in some circumstances. Future research on equine learning needs to take into account the complex nature of equine social interaction. Studies on the effects of stress on learning, and on social and spatial cognition, are also particularly needed.