Learning performances in young horses using two different learning tests

To achieve optimal performance in equine sports as well as in leisure not only the physical abilities of the horse should be considered, but also the horse’s personality. Besides temperamental aspects, like emotionality, or the horse’s reactivity towards humans in handling situations, the learning ability of the horse is another relevant personality trait. To study whether differences in learning performance are consistent over time and whether individual learning performance differs between learning tests or is affected by emotionality, 39 young horses (Dutch Warmblood) were tested repeatedly in two learning tests. An aversive stimulus (AS) was used in one learning test (the avoidance learning test) and a reward was used in the other learning test (the reward learning test). During both learning tests behaviour as well as heart rate were measured. Each test was executed four times, twice when horses were 1 year of age, and twice when they were 2 years of age. Half of the horses received additional physical training from 6 months onwards. In both tests horses could be classified as either performers, i.e. completing the daily session, or as non-performers, i.e. returning to the home environment without having completed the daily session. There were some indications that emotionality might have caused non-performing behaviour, but these indications are not convincing enough to exclude other causes. Furthermore, there seem to be no simple relationships between measures of heart rate, behavioural responses putatively related to emotionality and learning performance. Horses revealed consistent individual learning performances within years in both tests, and in the avoidance learning test also between years. There was no significant correlation between learning performances in the avoidance learning test and the learning performances in the reward learning test. It is concluded that individual learning abilities are consistent over a short time interval for an avoidance learning test and a reward learning test and over a longer time for the avoidance learning test. Furthermore, results indicate that some horses perform better when they have to learn to avoid an aversive stimulus while others perform better when they are rewarded after a correct response. It is suggested that these differences may be relevant to design optimal individual training programmes and methods.     

Review: Feeding conserved forage to horses: recent advances and recommendations

The horse is a non-ruminant herbivore adapted to eating plant-fibre or forage-based diets. Some horses are stabled for most or the majority of the day with limited or no access to fresh pasture and are fed preserved forage typically as hay or haylage and sometimes silage. This raises questions with respect to the quality and suitability of these preserved forages (considering production, nutritional content, digestibility as well as hygiene) and required quantities. Especially for performance horses, forage is often replaced with energy dense feedstuffs which can result in a reduction in the proportion of the diet that is forage based. This may adversely affect the health, welfare, behaviour and even performance of the horse. In the past 20 years a large body of research work has contributed to a better and deeper understanding of equine forage needs and the physiological and behavioural consequences if these are not met. Recent nutrient requirement systems have incorporated some, but not all, of this new knowledge into their recommendations. This review paper amalgamates recommendations based on the latest understanding in forage feeding for horses, defining forage types and preservation methods, hygienic quality, feed intake behaviour, typical nutrient composition, digestion and digestibility as well as health and performance implications. Based on this, consensual applied recommendations for feeding preserved forages are provided.     

Facial hair whorls (trichoglyphs) and the incidence of motor laterality in the horse

Several species demonstrate obvious motor laterality (sidedness, handedness) in their motor function. Motor laterality in the horse affects locomotion and subsequently equine performance during training and may have inherent safety implications for equitation. Some of the most commonly used identification features in the horse are hair whorls (trichoglyphs), since their specific location and character vary to some degree in every horse. We investigated the relationship between the hair flow of single facial hair whorls and the incidence of lateralised motor bias in 219 horses when under saddle in ridden work. The horses exhibited significant differences in motor preferences with 104 left-lateralised (LL) horses, 95 right-lateralised (RL) horses compared to only 20 well-balanced (WB) horses (chi(2)=36.9, d.f.=2, P<0.01). There was also a significant difference in the frequency distribution of single facial hair whorl patterns in the horses consisting of 114 horses with counter-clockwise (CC) whorls, 82 horses with clockwise (C) whorls and 23 horses, which had radial (R) whorls (chi(2)=38.87, d.f.=2, P<0.01). Overall there was a statistically significant association between motor behaviour and facial hair whorl patterns in the horses (chi(2)=69.4, d.f.=4, P>0.001). The RL horses had significantly more C facial hair whorls and the LL horses had significantly more CC facial hair whorls than would be expected purely by chance alone (P<0.05). The findings may provide trainers with a useful tool when attempting to identify simple, non-invasive and reliable predictors of motor laterality in the horse. Furthermore, given that efficient targeted training of performance horses during ridden work may produce WB equine athletes, the findings could assist trainers when designing individual-specific training programmes for young horses.     

Effect of reinforcement, reinforcer omission and extinction on a communicative response in domestic dogs (Canis familiaris)

There is a controversy about the mechanisms involved in the interspecific communicative behaviour in domestic dogs. The main question is whether this behaviour is a result of instrumental learning or higher cognitive skills are required. The present investigations were undertaken to study the effect of learning processes upon the gaze towards the human's face as a communicative response. To such purpose, in Study 1, gaze response was subjected to three types of reinforcement schedules: differential reinforcement, reinforcer omission, and extinction in a situation of “asking for food”. Results showed a significant increase in gaze duration in the differential reinforcement phase and a significant decrease in both the omission and extinction phases. These changes were quite rapid, since they occurred only after three training trials in each phase. Furthermore, extinction resulted in animal behaviour changes, such as an increase in the distance from the experimenter, the back position and lying behaviour. This is the first systematic evaluation of the behavioural changes caused by reward withdrawal (frustration) in dogs. In Study 2, the gaze response was studied in a situation where dogs walked along with their owners/trainers. These results show that learning plays an important role in this communicative response. The possible implications of these results for service dogs are discussed.     

Comparative histopathology of grey-horse-melanoma and human malignant melanoma

Equine melanoma shows striking features particularly with regard to clinical development in grey horses: in contrast to malignant melanoma in humans and in solid coloured horses that are characterized by early onset of metastasis, pigment cell tumours display almost benign clinical features in ageing grey horses. Through evolution, grey horses appear to be in a favourable position in regard to the biological behaviour of melanomas. Yet unknown factors inhibiting or retarding early melanoma metastasis may be responsible for this phenomenon. In this study, immunostaining profiles and histopathologic patterns of equine vs. human melanotic tumours were compared. In addition, the expression of melanoma markers currently used in human melanoma detection and characterization were evaluated for their applicability in equine melanoma diagnosis. Immunohistopathologic investigations revealed that benign grey horse melanomas share common features with human blue nevi and with human malignant desmoplastic melanomas, whereas their resemblance to other types of human cutaneous malignant melanomas is less pronounced. Our data equally underline that S-100, proliferating cell nuclear antigen (PCNA), HMB-45, Ki-67, T-311 and CD44 can serve as reliable markers for horse melanomas. Further investigations aiming at identifying factors retarding metastasis in affected grey horses are needed, as they may contribute to the development of novel treatment strategies for human malignant melanoma.     

Comparative Histopathology of Grey‐Horse‐Melanoma and Human Malignant Melanoma

Equine melanoma shows striking features particularly with regard to clinical development in grey horses: in contrast to malignant melanoma in humans and in solid coloured horses that are characterized by early onset of metastasis, pigment cell tumours display almost benign clinical features in ageing grey horses. Through evolution, grey horses appear to be in a favourable position in regard to the biological behaviour of melanomas. Yet unknown factors inhibiting or retarding early melanoma metastasis may be responsible for this phenomenon. In this study, immunostaining profiles and histopathologic patterns of equine vs. human melanotic tumours were compared. In addition, the expression of melanoma markers currently used in human melanoma detection and characterization were evaluated for their applicability in equine melanoma diagnosis. Immunohistopathologic investigations revealed that benign grey horse melanomas share common features with human blue nevi and with human malignant desmoplastic melanomas, whereas their resemblance to other types of human cutaneous malignant melanomas is less pronounced. Our data equally underline that S‐100, proliferating cell nuclear antigen (PCNA), HMB‐45, Ki‐67, T‐311 and CD44 can serve as reliable markers for horse melanomas. Further investigations aiming at identifying factors retarding metastasis in affected grey horses are needed, as they may contribute to the development of novel treatment strategies for human malignant melanoma.     

Landscape Utilisation,Animal Behaviour and Hendra Virus Risk

Hendra virus causes sporadic fatal disease in horses and humans in eastern Australia. Pteropid bats (flying-foxes) are the natural host of the virus. The mode of flying-fox to horse transmission remains unclear, but oro-nasal contact with flying-fox urine, faeces or saliva is the most plausible. We used GPS data logger technology to explore the landscape utilisation of black flying-foxes and horses to gain new insight into equine exposure risk. Flying-fox foraging was repetitious, with individuals returning night after night to the same location. There was a preference for fragmented arboreal landscape and non-native plant species, resulting in increased flying-fox activity around rural infrastructure. Our preliminary equine data logger study identified significant variation between diurnal and nocturnal grazing behaviour that, combined with the observed flying-fox foraging behaviour, could contribute to Hendra virus exposure risk. While we found no significant risk-exposing difference in individual horse movement behaviour in this study, the prospect warrants further investigation, as does the broader role of animal behaviour and landscape utilisation on the transmission dynamics of Hendra virus.     

The positive aspects of correct negative reinforcement

Abstract

In the scheme of contemporary animal training, horse training is virtually unique because it relies on negative reinforcement (NR) rather than positive reinforcement (PR). Furthermore, horse trainers are largely unaware that they are using NR in training. Instead, they believe in the benevolent nature of the horse and see their task in training as one of improving the balance and gymnastic ability of the horse—outcomes that emerge when the rider is similarly properly balanced. Under these conditions, it is claimed the willing horse will perform its required maneuvers. These beliefs may be associated with several welfare issues and indicate areas requiring future research: 1. The absence of release of pressure, the release of pressure at the wrong times, the use of opposing pressures simultaneously and the absence of shaping procedures are central to the development of acute and chronic stress responses in horses.

2. Resultant conflict behaviors contribute to equine wastage statistics and include behaviors that are dangerous to horses and humans.

3. There is a need for research into the mechanics of NR because it is poorly researched compared to PR.

4. When NR responses are installed correctly, only mild pressures need to be used, and results are obtained in few trials.

5. Many qualified animal trainers misunderstand NR and confuse it with punishment. They believe that PR has positive welfare implications and thus NR being “negative,” has negative welfare implications. So there is a need for horse trainers to understand learning theory and the principles that surround NR.

6. Horse trainers are isolated from advances in animal training. Therefore they increasingly seek knowledge and solutions from the growing number of “horse whisperers” and unqualified “horse psychologists.” This is potentially detrimental for the welfare of the horse and the need is urgent for universities throughout the world to become the knowledge bases for equitation science.

     

Equestrian Coaches' Understanding and Application of Learning Theory in Horse Training

ABSTRACT

To assess the knowledge of learning theory among accredited equestrian coaches in Australia, a 20-item questionnaire was distributed to all coaches registered with the National Coaches Accreditation Scheme in Australia (n = 830). Of the 206 respondents, 79.5% considered positive reinforcement to be “very useful,” yet only 2.8% correctly explained its use in horse training. When asked about the usefulness of negative reinforcement, 19.3% of coaches considered it “very useful,” with 11.9% correctly explaining its use. Punishment was rated “very useful” by 5.2% of respondents, although only eight coaches (5.4%) explained punishment correctly. Release of pressure was considered the most effective reward for horses among respondents (78.2%). These results indicate that many equestrian coaches lack a correct understanding of positive and negative reinforcement as they apply to horse training. Given that qualified coaches play a significant role in the dissemination of information on training practices, this highlights the need for improved education of equestrian coaches. Education to remedy this situation has the potential to enhance the welfare of horses through reduced behavioral conflict and improve training outcomes.     

Using differential reinforcement to improve equine welfare: shaping appropriate truck loading and feet handling

Inappropriate behavior during common handling procedures with horses is often subject to aversive treatment. The present study replicated and extended previous findings using differential reinforcement to shape appropriate equine handling behavior. In Study 1, a multiple baseline across subjects design was used with four horses to determine first the effects of shaping target-touch responses and then successive approximations of full truck loading under continuous and intermittent schedules of reinforcement. Full loading responses were shaped and maintained in all four horses and occurrences of inappropriate behaviors reduced to zero. Generalization of the loading response was also observed to both a novel trainer and trailer. In Study 2, a changing criterion design was used to increase the duration of feet handling with one horse. The horse's responding reached the terminal duration criterion of 1 min and showed consistent generalization and one-week maintenance. Overall, the results of both studies support the use of applied equine training systems based on positive reinforcement for increasing appropriate behavior during common handling procedures.     

Impacts of nutritional technology on feeds offered to horses: A review of effects of processing on voluntary intake,digesta characteristics and feed utilisation

Advances in feed processing technology applied to diet systems for ruminant livestock have been used extensively in the equine feed industry. The translation of these technologies is an important area of interest for the feed processing industry servicing the various sectors of the equine industry such as feeds for the racing, meat, milk and urine production, as well as supplements for leisure horse use. However, there are few reviews examining impacts of feed processing technologies on the processes controlling voluntary intake or utilisation of processed feeds by horses. In this paper, some of the specific features of feeds and impacts of feed processing on factors controlling meal pattern, frequency and size, and digestive physiology will be addressed. Three main areas are examined in this review, being impacts of feed processing on processes of “information gathering” (sensory and nutritional knowledge) by the horse, eating behaviour of the horse offered processed feeds (notably issues of preference and control of short-term ingestion rate), and implications of constraints of digestive physiology, process and function on voluntary intake and digestibility of processed feeds. The review highlights areas of future research and development for nutritional technology to increase knowledge of interactions between equine physiology and feed processing to enhance efficiency of capture of nutrients and maintain the welfare of horses managed in the housed environment.     

Preliminary study on current perceptions and usage of training equipment by horse enthusiasts in Canada

Training practices may impose restrictions on the equine behavioral repertoire through the use of training equipment. Presently, the prevalence of the use of training equipment in Canada is unknown. Through an online survey for horse enthusiasts (n = 654), this study evaluated the prevalence and predominant uses of whips, spurs, and head-control equipment by enthusiasts with direct contact with horses compared to perceptions held by enthusiasts with no direct horse contact using chi-squared analyses. Respondents primarily reported using whips and spurs to augment rider or trainer cues and reported using head-control equipment mainly for lunging purposes. The perceived frequency of spurs and head-control equipment use during riding or training by nonactive horse enthusiasts was significantly greater than reported usage by riders and trainers (p < .05). The results potentially indicate a lack of understanding and miscommunication of training equipment use by riders and trainers. The frequent reporting of training equipment for the purpose of augmenting rider cues may imply misinterpretation of the correct application of learning theory. These preliminary results warrant further investigation of equipment use within the horse industry.     

Behavioural flexibility and problem-solving in a tropical lizard

The role of behavioural flexibility in responding to new or changing environmental challenges is a central theme in cognitive ecology. Studies of behavioural flexibility have focused mostly on mammals and birds because theory predicts that behavioural flexibility is favoured in species or clades that exploit a diversity of habitats or food sources and/or have complex social structure, attributes not associated with ectothermic vertebrates. Here, we present the results of a series of experiments designed to test cognitive abilities across multiple cognitive modules in a tropical arboreal lizard: Anolis evermanni. This lizard shows behavioural flexibility across multiple cognitive tasks, including solving a novel motor task using multiple strategies and reversal learning, as well as rapid associative learning. This flexibility was unexpected because lizards are commonly believed to have limited cognitive abilities and highly stereotyped behaviour. Our findings indicate that the cognitive abilities of A. evermanni are comparable with those of some endothermic species that are recognized to be highly flexible, and strongly suggest a re-thinking of our understanding of the cognitive abilities of ectothermic tetrapods and of the factors favouring the evolution of behavioural flexibility.     

Keeping horses in groups: A review

Although husbandry conditions for horses have improved over the last decades, many horses are still kept singly with limited or no physical contact to other horses. This is surprising, given the fact that keeping horses in groups is recognised best to fulfil their physical and behavioural needs, especially their need for social contact with conspecifics, as well as to have a beneficial effect on horse–human interactions during training.Group housing of farm animals is widely applied in practice. As a consequence, scientists have investigated numerous aspects of group housing to help further improve animal welfare and human–animal interactions under these conditions. However, compared to this literature available in farm animals, and the plentiful studies conducted of feral horse populations, there is much less done when it comes to the management of horses kept in groups in the domestic environment. In particular, limited scientific information is available into the effect of group size and group composition on behaviour and methods of introducing new horses into established groups, even though problems related to social integration are repeatedly taken as arguments against keeping horses in groups.This review, therefore, aims to provide an overview of the current scientific knowledge regarding keeping horses in groups. Furthermore, it aims to give insight into whether or not some of the concerns related to keeping horses in groups are justified and to review scientifically based solutions that could be useful in practice to improve horse welfare and human safety.     

Is there evidence of learned helplessness in horses?

Learned helplessness is a psychological condition whereby individuals learn that they have no control over unpleasant or harmful conditions, that their actions are futile, and that they are helpless. In a series of experiments in which dogs were exposed to inescapable shocks, this lack of control subsequently interfered with the ability to learn an avoidance task. There is evidence that both neural adaptations and behavioral despair occur in response to uncontrollable aversive experiences in rodents, although this has yet to be demonstrated in other species such as horses. However, certain traditional methods of horse training and some behavioral modification techniques--it has been suggested--may involve aversive conditions over which the horse has little or no control. When training and management procedures are repeatedly unpleasant for the horse and there is no clear association between behavior and outcome, this is likely to interfere with learning and performance-in addition to compromising welfare. This article reviews published literature and anecdotal evidence to explore the possibility that the phenomenon, learned helplessness, occurs in the horse.     

Ecological Interactions Involving Feral Horses and Predators: Review with Implications for Biodiversity Conservation

For many ecosystems, feral horses are increasingly becoming an important if not dominant component of ungulate biomass and hence influence on community dynamics. Yet we still know little of how horses contribute to key ecological interactions including predator-prey and indirect competitive relationships at a community level. Notably, feral species like horses can exhibit life-history traits that differ from that of native (mainly artiodactyl) herbivore competitors. Artificial selection for traits like increased, early, or extended reproduction that have yet to be reversed by natural selection, coupled with naturally selected differences in anatomy and behavior, in addition to unique management objectives for horses compared to other species, means that the dynamics of feral horse populations are not likely to align with what might be expected of other large herbivores. Unexpected population dynamics and inherent biological asymmetries between native ungulates and feral horses may therefore influence the former via direct competition for shared resources and through enemy-mediated interactions like apparent competition. In several localities feral horses now co-exist with multiple native prey species, some of which are in decline or are species at risk. Compounding risks to native species from direct or indirect competitive exclusion by horses is the unique nature and socio-political context of feral horse management, which tends towards allowing horse populations to be limited largely by natural, density-dependent factors. We summarize the inherent asymmetries between feral horse biology and that of other ungulate prey species with consequences for conservation, focusing on predator-prey and emerging indirect interactions in multi-prey systems, and highlight future directions to address key knowledge gaps in our understanding of how feral horses may now be contributing to the (re)structuring of food webs. Observations of patterns of rapid growth and decline, and associated skews in sex ratios of feral horse populations, indicate a heightened potential for indirect interactions among large ungulate prey species, where there is a prevalence of feral horses as preferred prey, particularly where native prey are declining. In places like western North America, we expect predator-prey interactions involving feral horses to become an increasingly important factor in the conservation of wildlife. This applies not only to economically or culturally important game species but also at-risk species, both predators (e.g., wolves [Canis lupus], grizzly bears [Ursus arctos]) and prey (e.g., woodland caribou [Rangifer tarandus caribou]), necessitating an ecological understanding of the role of horses in natural environments that goes beyond that of population control. © 2021 The Wildlife Society.     

Introduction to automatic forage stations and measurement of forage intake rate in an active open barn for horses

Interest in the use of open barns on Swedish horse farms is increasing as an alternative to keeping horses in box stalls and as a 2007 law requires phasing out of tie stalls. To provide adequate forage to satisfy welfare requirements for nutrition, gut health and behavioural needs, the use of automated feeding is also increasing. Studies on forage intake rate report wide variation but provide little information on how to introduce horses to an automatic forage station and on how forage intake rate varies in individual horses fed using an automatic forage station. This study documented the process of training 22 horses to use a transponder-controlled automatic forage feeding station and measured forage intake rates. Observations on the learning period of horses for transponder-controlled automatic forage stations showed that after 4 days, 48% of the horses had reached the goal of 90% intake. After 8 days, learning was completed in 71% of horses and at 16 days in 95% of horses. Measurements of forage intake rate revealed significant differences between individual horses. Overall mean intake rate ± SD, based on 314 observations, was 22.4 ± 6.7 min/kg forage DM. Evaluation of the number of intake measurements required to set a representative average ration in the automatic station for an individual horse showed that the variation levelled off at four samples. In conclusion, horses quickly learned how to use an automatic forage station, with two-thirds of horses achieving this within 7 days. To ensure the correct ration in a timed transponder-controlled automatic forage station, each horse’s forage intake rate must be measured at least four times to obtain a representative average.     

Metabolism of Immunoglobulin-G in the Horse

The metabolism of immunoglobulin classes has been closely examined in several animal species. Although the horse has received much attention in experimental and applied immunology there seems to be little information available on immunoglobulin kinetics in this species. The present report describes the metabolism of equine IgG in 4 healthy, normoimmunoglobulinaemic horses, in 1 horse with hyperimmunoglobulinaemia and in 1 horse with relatively low immunoglobulin levels.     

The equine neck and its function during movement and locomotion

During both locomotion and body movements at stance, the head and neck of the horse are a major craniocaudal and lateral balancing mechanism employing input from the visual, vestibular and proprioceptive systems. The function of the equine neck has recently become the focus of several research groups; this is probably also feeding on an increase of interest in the equine neck in equestrian sports, with a controversial discussion of specific neck positions such as maximum head and neck flexion. The aim of this review is to offer an overview of new findings on the structures and functions of the equine neck, illustrating their interplay. The movement of the neck is based on intervertebral motion, but it is also an integral part of locomotion; this is illustrated by the different neck conformations in the breeds of horses used for various types of work. The considerable effect of the neck movement and posture onto the whole trunk and even the limbs is transmitted via bony, ligamentous and muscular structures. Also, the fact that the neck position can easily be influenced by the rider and/or by the employment of training aids makes it an important avenue for training of new movements of the neck as well as the whole horse. Additionally, the neck position also affects the cervical spinal cord as well as the roots of the spinal nerves; besides the commonly encountered long-term neurological effects of cervical vertebral disorders, short-term changes of neural and muscular function have also been identified in the maximum flexion of the cranial neck and head position. During locomotion, the neck stores elastic energy within the passive tissues such as ligaments, joint capsules and fasciae. For adequate stabilisation, additional muscle activity is necessary; this is learned and requires constant muscle training as it is essential to prevent excessive wear and tear on the vertebral joints and also repetitive or single trauma to the spinal nerves and the spinal cord. The capability for this stabilisation decreases with age in the majority of horses due to changes in muscle tissue, muscle coordination and consequently muscle strength.     

Selective grazing behaviour in horses: development of methodology and preliminary use of tests to measure individual grazing ability

Methods are described to assess horses' selective grazing ability that includes choosing, sorting and the adaptive value of this behaviour. Choosing ability was tested by the experimenter presenting pairs of cut plant species that were then alternated at each presentation until the test horse had taken three bites of one of the plant pair. The results were analysed in relation to five measures of choosing behaviour: (1) the strength of the choice; (2) correspondence between first bite and the final choice; (3) constancy of the choice over a number of trials; (4) the comparison of the horses' ranking of the species over a number of trials; (5) the constancy of the linear arrangement of the plants over a number of trials. Sorting ability was tested using two methods. A mixture of two plant species was presented either in a clamp or loose in a trough. Results were based on number and weight of plant residues. The adaptive value of the behaviour related to the bitterness of toxic plants. This bitterness was represented in testing by quinine sulphate and a poisonous Senecio species. An extremely bitter substance “Bitrex” was also used in this context but was totally accepted by the horses. The horses' reactions to these substances were monitored using a behavioural score chart.

The results from 12 horses revealed that the horses differed individually in their grazing ability. On this basis, the horses were classified as efficient, semi-efficient, or inefficient grazers. This finding has practical implications in deciding which horses may safely graze on pastures infested with toxic plants.