Sensory perception in horses involves the processing and interpretation of sensory stimuli from the environment through various sensory modalities. Horses rely on their senses, including vision, hearing, touch, taste, and smell, to interact with their surroundings and respond to potential threats or opportunities. Vision in horses is adapted for detecting movement and changes in light, with a wide field of view due to the lateral placement of their eyes. Their hearing is sensitive to a range of frequencies, allowing them to detect sounds over long distances. The tactile sense is facilitated by whiskers and sensitive skin, particularly around the muzzle, aiding in exploration and communication. Taste and smell play roles in feeding behavior and social interactions. This page compiles peer-reviewed research studies and scholarly articles that explore the anatomical structures, physiological mechanisms, and behavioral implications of sensory perception in equine species.
Keller P, Hudders L, Decloedt A.Complementary and alternative veterinary medicine (CAVM) is increasingly popular in horses. As CAVM usage could have risks, client-veterinarian communication about CAVM is crucial. Objective: Evaluating equine veterinarians' attitude towards CAVM, their CAVM usage and veterinarian-client communication about CAVM. Methods: Cross-sectional study. Methods: A telephone survey was conducted among equine veterinarians providing ambulatory care on a daily or weekly basis. The first section of the survey included questions about the veterinarians' attitude towards CAVM and their CAVM usage. The second...
Cerebral lateralisation is the tendency for an individual to preferentially use one side of their brain and is apparent in the biased use of paired sensory organs. Horses vary in eye use when viewing a novel stimulus which may be due to different physiological reactions. To understand the interplay between physiology and lateralisation, we presented a novel object (an inflated balloon) to 20 horses while electrocardiogram traces were collected. We measured the amount of time each horse looked at the balloon with each eye. We calculated 'sample entropy' as a measure of non-linear heart rate var...
Rogers LJ.The specialized functions of each hemisphere of the vertebrate brain are summarized together with the current evidence of lateralized behavior in farm and companion animals, as shown by the eye or ear used to attend and respond to stimuli. Forelimb preference is another manifestation of hemispheric lateralization, as shown by differences in behavior between left- and right-handed primates, left- and right-pawed dogs and cats, and left- and right-limb-preferring horses. Left-limb preference reflects right hemisphere use and is associated with negative cognitive bias. Positive cognitive bias is ...
Haddy E, Burden F, Raw Z, Rodrigues JB, Zappi Bello JH, Brown J, Kaminski J, Proops L.Belief in animal sentience and the quality of human-animal relationships play a significant role in animal welfare. However, the link between an individual animal's welfare and the beliefs and emotional connection of the owner to the animal is understudied and focussed on single cultures, limiting generalisability. In this study, we explored potential links between owner attitude, beliefs in animal sentience, and working equid welfare across four continents. This study used a welfare assessment protocol alongside a questionnaire exploring owner attitudes to assess 378 participants across six c...
Forino S, Cameron L, Stones N, Freeman M.The ideal equestrian body image (BI) is a smaller physique and riders feel body shape (BS) influences subjective judge scoring within dressage competitions. The aims were to identify perceptions of equestrian coaches and dressage judges of rider body shape (BS), identify perceptions of appropriate horse-rider matching and establish the impact of BS on perceived rider ability. An online survey (GoogleFormsTM) was shared, respondents (n = 265, coaches = 174 judges = 91) viewed images of twelve riders of different BS (Ectomorph, Mesomorph, and Endomorph) mounted on three horses of different...
Bampidis V, Azimonti G, Bastos ML, Christensen H, Durjava M, Kouba M, López-Alonso M, López Puente S, Marcon F, Mayo B, Pechová A, Petkova M....Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of 4-methyl-5-vinylthiazole [15.018] belonging to chemical group 29 (thiazoles, thiophene and thiazoline), when used as sensory additive (flavourings) in feed for all animal species. The FEEDAP Panel concluded that 4-methyl-5-vinylthiazole [15.018] was safe at the maximum proposed use level of 0.5 mg/kg complete feed for veal calves (milk replacer), dogs, salmonids and ornamental fish. For the other species, the calculated safe concentrations in complete feed are: 0.4â€...
Tomberg C, Petagna M, de Selliers de Moranville LA.Facial micro-expressions are facial expressions expressed briefly (less than 500Â ms) and involuntarily. Described only in humans, we investigated whether micro-expressions could also be expressed by non-human animal species. Using the Equine Facial action coding system (EquiFACS), an objective tool based on facial muscles actions, we demonstrated that a non-human species, Equus caballus, is expressing facial micro-expressions in a social context. The AU17, AD38 and AD1 were selectively modulated as micro-expression-but not as standard facial expression (all durations included)-in presence of ...
Hole C, Murray R, Marlin D, Freeman P.Despite numerous studies investigating responses to visual perception, there is limited research into how horses respond to different auditory stimuli. Although 'noise-damping' ear covers are frequently used on sport horses to minimise distraction from external auditory stimuli, the effectiveness of ear covers has not been established. This study aimed to (i) investigate the responses of horses to different sounds commonly present in a competition environment, and (ii) compare these responses in the presence and absence of ear covers. A total of 18 horses were presented with 5 sounds commonly ...
Kropich-Grant JN, Wiley KE, Manyweathers J, Thompson KR, Brookes VJ.Hendra virus disease (HeVD) is an emerging zoonosis in Australia, resulting from the transmission of Hendra virus (HeV) to horses from Pteropus bats. Vaccine uptake for horses is low despite the high case fatality rate of HeVD in both horses and people. We reviewed evidence-based communication interventions to promote and improve HeV vaccine uptake for horses by horse owners and conducted a preliminary evaluation of potential drivers for HeV vaccine uptake using the Behavioural and Social Drivers of Vaccination (BeSD) framework developed by the World Health Organization. Six records were eligi...
Bampidis V, Azimonti G, Bastos ML, Christensen H, Durjava M, Kouba M, López-Alonso M, López Puente S, Marcon F, Mayo B, Pechová A, Petkova M....Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of an essential oil obtained from the oleoresin of Aiton (pine white oil, also known as turpentine oil), when used as a sensory additive in feed and water for drinking for all animal species. The Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded that the essential oil under assessment is safe up to the maximum proposed use levels of 35 mg/kg for laying hens, piglets, pigs for fattening, sows, rabbits, salmonids, 50 mg/kg for veal ca...
Bampidis V, Azimonti G, Bastos ML, Christensen H, Durjava M, Kouba M, López-Alonso M, López Puente S, Marcon F, Mayo B, Pechová A, Petkova M....Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of a tincture from the fruit of L. (anise tincture) when used as a sensory additive in feed and water for drinking for all animal species. The product is a â– â– â– â– â– solution, with a dry matter content of approximately 1.6%. The product contained on average 0.0414% polyphenols (of which 0.0144% were flavonoids), 0.0009% anisaldehyde, 0.0003% anethole. Estragole (≤ 1.2 mg/kg) was detected in the additive. The estimated maximum content of furocoumarins was 8.2â...
Golding E, Al Ansari ASA, Sutton GA, Walshe N, Duggan V.Equine obesity is a significant health and welfare concern. The proportion of domestic horse populations that are overweight are as high as 45%. As the primary decision-makers for their horses' care, owners are theoretically ideally placed to identify whether their horses are appropriately conditioned, however, research in other countries has shown that many owners are unable to accurately judge their horse's body condition. In this study, through the comparison of body condition scoring (BCS) performed by an expert and the horse owners and interviews with owners, we aimed to identify the prop...
Heleski CR.What is a social license to operate (SLO)? Why would this concept matter for horse sport? In perhaps its simplest form, "social license to operate" is the public's perception of an industry or activity. It is a challenging concept to fully grasp because it does not arrive as a document given by a government agency. Yet it is every bit as important-perhaps more so. Does the industry in question operate with transparency? Does the public believe in the integrity of the stakeholders who are most likely to benefit from the activity? Do people believe there is legitimacy in the scrutinized industry...
Gouyet C, Ringhofer M, Yamamoto S, Jardat P, Parias C, Reigner F, Calandreau L, Lansade L.Several studies have shown that horses have the ability to cross-modally recognize humans by associating their voice with their physical appearance. However, it remains unclear whether horses are able to differentiate humans according to different criteria, such as the fact that they are women or men. Horses might recognize some human characteristics, such as sex, and use these characteristics to classify them into different categories. The aim of this study was to explore whether domesticated horses are able to cross-modally recognize women and men according to visual and auditory cues, using...
Kappel S, Ramirez Montes De Oca MA, Collins S, Herborn K, Mendl M, Fureix C.The use of 2-dimensional representations (e.g. photographs or digital images) of real-life physical objects has been an important tool in studies of animal cognition. Horses are reported to recognise objects and individuals (conspecifics and humans) from printed photographs, but it is unclear whether image recognition is also true for digital images, e.g. computer projections. We expected that horses trained to discriminate between two real-life objects would show the same learnt response to digital images of these objects indicating that the images were perceived as objects, or representation...
Bampidis V, Azimonti G, Bastos ML, Christensen H, Durjava M, Kouba M, López-Alonso M, López Puente S, Marcon F, Mayo B, Pechová A, Petkova M....Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of a tincture from the roots of (Rupr. & Maxim.) Maxim. (taiga root tincture) when used as a sensory additive in feed for dogs, cats and horses. The Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded that the additive is safe for dogs, cats and horses at the maximum proposed use level of 460.7, 489.5 and 140.7 mg/kg complete feed, respectively. The additive was considered safe for consumers when used at the proposed conditions of us...
Caro T, Fogg E, Stephens-Collins T, Santon M, How MJ.Stripes deter horseflies (tabanids) from landing on zebras and, while several mechanisms have been proposed, these hypotheses have yet to be tested satisfactorily. Here, we investigated three possible visual mechanisms that could impede successful tabanid landings (aliasing, contrast and polarization) but additionally explored pattern element size employing video footage of horseflies around differently patterned coats placed on domestic horses. We found that horseflies are averse to landing on highly but not on lightly contrasting stripes printed on horse coats. We could find no evidence for ...
Rochais C, Lerch N, Gueguen L, Schmidlin M, Bonamy O, Grandgeorge M, Hausberger M.Tactile perception in humans varies between individuals and could depend on extrinsic factors such as working activity. In animals, there is no study relating the influence of animals' work and their tactile reactivity . We investigated horses' tactile reactivity using von Frey filament in different body areas and compared horses working only in equine-assisted interventions (EAI), in riding school (RS) lessons, and in both activities (EAI-RS). We further compared tactile actions by people with or without mental and/or developmental disorders during brushing sessions. The results indicated tha...
Chun J, Kang T, Seo JP, Jeong H, Kim M, Kim BS, Ahn M, Kim J, Shin T.Vomeronasal organ (VNO) is a tubular pheromone sensing organ in which the lumen is covered with sensory and non-sensory epithelia. This study used immunohistochemistry and lectin histochemistry techniques to evaluate developmental changes, specifically of the glycoconjugate profile, in the horse VNO epithelium. Immunostaining analysis revealed PGP9.5 expression in some vomeronasal non-sensory epithelium (VNSE) cells and in the vomeronasal receptor cells of the vomeronasal sensory epithelium (VSE) in fetuses, young foals, and adult horses. OMP expression was exclusively localized in receptor ce...
Bampidis V, Azimonti G, Bastos ML, Christensen H, Fašmon Durjava M, Kouba M, López-Alonso M, López Puente S, Marcon F, Mayo B, Pechová A....Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of a tincture from the fruit of Mill. ssp. v var. (sweet fennel tincture) when used as a sensory additive in feed and water for drinking for all animal species. The product is a ■■■■■solution, with a dry matter content of approximately 2.16%. The product contained 0.0586% polyphenols (of which 0.0052% were flavonoids), anethole (0.0006%), anisaldehyde (0.0035%) and estragole (0.0006%). The Panel on Additives and Products or Substances used in Animal Feed (FE...
Bampidis V, Azimonti G, Bastos ML, Christensen H, Fašmon Durjava M, Kouba M, López-Alonso M, López Puente S, Marcon F, Mayo B, Pechová A....Following a request from the European Commission, EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety and efficacy of a tincture derived from the fruit of (Mill.) Fuss (parsley tincture) when used as a sensory feed additive for all animal species. The product is a ■■■■■solution, with a dry matter content of approximately 0.82%. The product contained 0.0198% polyphenols (of which 0.0085% were flavonoids), apiole (0.0083%), elemicin (0.0015%) and myristicin (0.0011%). The Panel on Additives and Prod...
Dai F, Riva MG, Dalla Costa E, Pascuzzo R, Chapman A, Minero M.To identify feasible indicators to evaluate animals' emotional states as a parameter to assess animal welfare, the present study aimed at investigating the accuracy of free choice profiling (FCP) and fixed list (FL) approach of Qualitative Behaviour Assessment (QBA) in horses during the loading phase of transport. A total of 13 stakeholders were trained to score 2 different sets of videos of mixed breed horses loaded for road transport, using both FCP and FL, in 2 sessions. Generalized Procustes Analysis (GPA) consensus profile explained a higher percentage of variation (80.8%) than the mean o...
Bampidis V, Azimonti G, Bastos ML, Christensen H, Fašmon Durjava M, Kouba M, López-Alonso M, López Puente S, Marcon F, Mayo B, Pechová A....Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of a tincture from the fruit (pericarps and seeds) of Hook f. (star anise tincture) when used as a sensory feed additive for all animal species. The product is a ■■■■■solution, with a dry matter content of approximately 1.86%. The product contained on average 0.2588% polyphenols (of which 0.0229% were flavonoids, including 0.0036% rutin), anethole (0.018%) and estragole (0.00039%). The Panel on Additives and Products or Substances used in Animal Feed (FEEDAP)...
Schubert CL, Ryckewaert B, Pereira C, Matsuzawa T.This study aimed to use a computer-controlled touchscreen system to examine visual discrimination in Garrano horses (), an endangered breed of pony belonging to the Iberian horse family. This pilot study focused on the perceptual similarity among letters of the alphabet. We tested five horses in a one-male unit (OMU) living permanently in a semi-free enclosure near their natural habitat in Serra d'Arga, northern Portugal. Horses were trained to nose-touch black circles that appeared on the screen. Then, they were tested for discrimination of five letters of the Latin alphabet in Arial font, na...
Cox EG, Bell R, Greer RM, Jeffcott LB.The practice of horse rugging has important implications for horse welfare and performance, but in Australia, rugging practices have not been properly documented. The objective of this study was to obtain an understanding of Australian horse rugging practices. An online survey reviewed the management of 2659 Australian horses over 12 months. Of the reported horses a total of 84.8% were rugged, although most owners (69.5%) indicated that they were unsure whether horses needed to be rugged at all. Rugging was felt by 59.8% of owners to be a requirement for horses in competition. Riding and com...
Mattila M, Honkanen S, Sjögren T, Piirainen A, Aartolahti E.Interaction has a multidimensional role in equine-facilitated rehabilitation. Unassigned: The aim of this study was to understand rehabilitees' experiences of interaction during equine-facilitated rehabilitation. Unassigned: Six children and four adults with individual diagnoses or reasons to participate in equine-facilitated rehabilitation were included in this qualitative study. Data were collected by interviewing individually the rehabilitees. A phenomenological Spiegelberg's seven-phase meaning analysis was performed to reveal the meanings. Unassigned: Seven meanings were identified: 1) Tr...
Janicka W, Wilk I, Próchniak T, Janczarek I.Virtual fencing is an innovative alternative to conventional fences. Different systems have been studied, including electric-impulse-free systems. We tested the potential of self-applied acoustic stimulus in deterring the horses from further movement. Thirty warmblood horses were individually introduced to a designated corridor leading toward a food reward (variant F) or a familiar horse (variant S). As the subject reached a distance of 30, 15 or 5 m from a finish line, an acute alarming sound was played. Generally, a sudden and unknown sound was perceived by horses as a threat causing an incr...
Smith R, Furtado T, Brigden C, Pinchbeck G, Perkins E.Human assessment of equine wellbeing is fundamental to ensuring the optimal care of domestic horses. However, terminology associated with wellbeing is still not fully defined and there are currently no validated quality of life (QoL) assessment tools. Furthermore, little is known about what equine wellbeing or QoL means to horse owners, or how their beliefs impact on the management decisions they make for their horse. This study sought to establish how UK leisure horse owners use wellbeing-related terminology by exploring their accounts within a focus group setting. Four online focus group dis...
Rogers S, Bell C.One of the key welfare concerns for horses in the United Kingdom is lack of recognition of fear in horses. This study aimed to gain an understanding of how well horse care givers recognise fear and/or anxiety in horses by interviewing equine behaviourists (who interact with large numbers of horse care givers and talk to them about this topic routinely). The experiences of Animal Behaviour and Training Council (ABTC)-registered equine behaviourists working with horse caregivers were examined, including the ability of clients to recognise fear and/or anxiety in horses, how clients respond when d...
Bampidis V, Azimonti G, Bastos ML, Christensen H, Fašmon Durjava M, Kouba M, López-Alonso M, López Puente S, Marcon F, Mayo B, Pechová A....Following a request from the European Commission, the EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety and efficacy of an essential oil from leaves, stalks and twigs of (L.) J. Presl (cassia leaf oil) when used as a sensory additive (flavouring) in feed and water for drinking for all animal species. Owing to the presence of styrene in cassia leaf oil, the FEEDAP Panel is not in the position to conclude for long-living animals and animals for reproduction. For 'short-living' animals, the FEEDAP Panel conc...
Proops L, McComb K, Reby D.Individual recognition is considered a complex process and, although it is believed to be widespread across animal taxa, the cognitive mechanisms underlying this ability are poorly understood. An essential feature of individual recognition in humans is that it is cross-modal, allowing the matching of current sensory cues to identity with stored information about that specific individual from other modalities. Here, we use a cross-modal expectancy violation paradigm to provide a clear and systematic demonstration of cross-modal individual recognition in a nonhuman animal: the domestic horse. Su...
Smith AV, Proops L, Grounds K, Wathan J, McComb K.Whether non-human animals can recognize human signals, including emotions, has both scientific and applied importance, and is particularly relevant for domesticated species. This study presents the first evidence of horses' abilities to spontaneously discriminate between positive (happy) and negative (angry) human facial expressions in photographs. Our results showed that the angry faces induced responses indicative of a functional understanding of the stimuli: horses displayed a left-gaze bias (a lateralization generally associated with stimuli perceived as negative) and a quicker increase in...
Proops L, McComb K.It has recently been shown that some non-human animals can cross-modally recognize members of their own taxon. What is unclear is just how plastic this recognition system can be. In this study, we investigate whether an animal, the domestic horse, is capable of spontaneous cross-modal recognition of individuals from a morphologically very different species. We also provide the first insights into how cross-modal identity information is processed by examining whether there are hemispheric biases in this important social skill. In our preferential looking paradigm, subjects were presented with t...
De Boyer Des Roches A, Richard-Yris MA, Henry S, Ezzaouïa M, Hausberger M.Lateralization of emotions has received great attention in the last decades, both in humans and animals, but little interest has been given to side bias in perceptual processing. Here, we investigated the influence of the emotional valence of stimuli on visual and olfactory explorations by horses, a large mammalian species with two large monocular visual fields and almost complete decussation of optic fibres. We confronted 38 Arab mares to three objects with either a positive, negative or neutral emotional valence (novel object). The results revealed a gradient of exploration of the 3 objects ...
Proops L, McComb K.Recent research has shown that domestic dogs are particularly good at determining the focus of human attention, often outperforming chimpanzees and hand-reared wolves. It has been suggested that the close evolutionary relationship between humans and dogs has led to the development of this ability; however, very few other domestic species have been studied. We tested the ability of 36 domestic horses to discriminate between an attentive and inattentive person in determining whom to approach for food. The cues provided were body orientation, head orientation or whether the experimenters' eyes we...
Uller C, Lewis J.The ability to select the greater numerosity over another in small sets seems to stem from the calculation of which set contains more, and has been taken as evidence of a primordial representation at the roots of the primate numerical system. We tested 56 horses (Equus caballus) in a paradigm previously used with human infants and nonhuman primates. Horses saw two quantities paired in contrasts-2 versus 1, 3 versus 2, 6 versus 4 and a control for volume, 2 versus 1 big-and had to make a choice by snout touching the container holding the numerosity selected. The horses spontaneously selected th...
Maros K, Gácsi M, Miklósi A.Twenty domestic horses (Equus caballus) were tested for their ability to rely on different human gesticular cues in a two-way object choice task. An experimenter hid food under one of two bowls and after baiting, indicated the location of the food to the subjects by using one of four different cues. Horses could locate the hidden reward on the basis of the distal dynamic-sustained, proximal momentary and proximal dynamic-sustained pointing gestures but failed to perform above chance level when the experimenter performed a distal momentary pointing gesture. The results revealed that horses coul...
Lampe JF, Andre J.This study has shown that domestic horses are capable of cross-modal recognition of familiar humans. It was demonstrated that horses are able to discriminate between the voices of a familiar and an unfamiliar human without seeing or smelling them at the same moment. Conversely, they were able to discriminate the same persons when only exposed to their visual and olfactory cues, without being stimulated by their voices. A cross-modal expectancy violation setup was employed; subjects were exposed both to trials with incongruent auditory and visual/olfactory identity cues and trials with congruen...
Sankey C, Richard-Yris MA, Henry S, Fureix C, Nassur F, Hausberger M.A central question in the interspecific human/animal relationship is how domestic animals perceive humans as a significant element of their environment. In this study, we tested the hypothesis that the use of positive or negative reinforcement in horse training may have consequences on the animals' perception of humans, as a positive, negative or neutral element. Two groups of ponies were trained to walk backwards in response to a vocal order using either positive or negative reinforcement. Heart rate monitors and behavioural observations were used to assess the animals' perception of humans o...
Larose C, Richard-Yris MA, Hausberger M, Rogers LJ.We have established that lateral biases are characteristic of visual behaviour in 65 horses. Two breeds, Trotters and French Saddlebreds aged 2 to 3, were tested on a novel object test. The main finding was a significant correlation between emotionality index and the eye preferred to view the novel stimulus: the higher the emotionality, the more likely that the horse looked with its left eye. The less emotive French Saddlebreds, however, tended to glance at the object using the right eye, a tendency that was not found in the Trotters, although the emotive index was the same for both breeds. Th...
Lemasson A, Boutin A, Boivin S, Blois-Heulin C, Hausberger M.Many animal species that rely mainly on calls to communicate produce individual acoustic structures, but we wondered whether individuals of species better known as visual communicants, with small vocal repertoires, would also exhibit individual distinctiveness in calls. Moreover, theoretical advances concerning the evolution of social intelligence are usually based on primate species data, but relatively little is known about the social cognitive capacities of non-primate mammals. However, some non-primate species demonstrate auditory recognition of social categories and possess mental represe...
How MJ, Zanker JM.The functional significance of the zebra coat stripe pattern is one of the oldest questions in evolutionary biology, having troubled scientists ever since Charles Darwin and Alfred Russel Wallace first disagreed on the subject. While different theories have been put forward to address this question, the idea that the stripes act to confuse or 'dazzle' observers remains one of the most plausible. However, the specific mechanisms by which this may operate have not been investigated in detail. In this paper, we investigate how motion of the zebra's high contrast stripes creates visual effects tha...
Hintze S, Melotti L, Colosio S, Bailoo JD, Boada-Saña M, Würbel H, Murphy E.Judgement bias tasks are promising tools to assess emotional valence in animals, however current designs are often time-consuming and lack aspects of validity. This study aimed to establish an improved design that addresses these issues and can be used across species. Horses, rats, and mice were trained on a spatial Go/No-go task where animals could initiate each trial. The location of an open goal-box, at either end of a row of five goal-boxes, signalled either reward (positive trial) or non-reward (negative trial). Animals first learned to approach the goal-box in positive trials (Go) and to...
Arkell M, Archer RM, Guitian FJ, May SA.Eighteen observers were influenced to different extents in the grades of lameness they allocated to eight horses by whether they knew that a nerve block had been administered; on a scale from 0 to 10 the mean difference in grade allocated once the observer knew a horse had been nerve-blocked was increased by 0.4. The consistency of the assessments made by the individual observers was good, with a an average of 0.6 of a grade difference when grading the same horse on two occasions. The agreement between the assessments of four orthopaedic experts was reasonable (+/-1 grade), but significantly p...
Wathan J, Proops L, Grounds K, McComb K.In humans, facial expressions are rich sources of social information and have an important role in regulating social interactions. However, the extent to which this is true in non-human animals, and particularly in non-primates, remains largely unknown. Therefore we tested whether domestic horses (Equus caballus) could discriminate between facial expressions of their conspecifics captured in different contexts, and whether viewing these expressions elicited functionally relevant reactions. Horses were more likely to approach photographic stimuli displaying facial expressions associated with po...
Henry S, Fureix C, Rowberry R, Bateson M, Hausberger M.This field study tested the hypothesis that domestic horses living under putatively challenging-to-welfare conditions (for example involving social, spatial, feeding constraints) would present signs of poor welfare and co-occurring pessimistic judgement biases. Our subjects were 34 horses who had been housed for over 3Â years in either restricted riding school situations (e.g. kept in single boxes, with limited roughage, ridden by inexperienced riders; NÂ =Â 25) or under more naturalistic conditions (e.g. access to free-range, kept in stable social groups, leisure riding; NÂ =Â 9). The horses'...
Farmer K, Krueger K, Byrne RW.Most horses have a side on which they are easier to handle and a direction they favour when working on a circle, and recent studies have suggested a correlation between emotion and visual laterality when horses observe inanimate objects. As such lateralisation could provide important clues regarding the horse's cognitive processes, we investigated whether horses also show laterality in association with people. We gave horses the choice of entering a chute to left or right, with and without the passive, non-interactive presence of a person unknown to them. The left eye was preferred for scannin...
Smith AV, Proops L, Grounds K, Wathan J, Scott SK, McComb K.The ability to discriminate between emotion in vocal signals is highly adaptive in social species. It may also be adaptive for domestic species to distinguish such signals in humans. Here we present a playback study investigating whether horses spontaneously respond in a functionally relevant way towards positive and negative emotion in human nonverbal vocalisations. We presented horses with positively- and negatively-valenced human vocalisations (laughter and growling, respectively) in the absence of all other emotional cues. Horses were found to adopt a freeze posture for significantly longe...
Krueger K, Flauger B, Farmer K, Maros K.This study evaluates the horse (Equus caballus) use of human local enhancement cues and reaction to human attention when making feeding decisions. The superior performance of dogs in observing human states of attention suggests this ability evolved with domestication. However, some species show an improved ability to read human cues through socialization and training. We observed 60 horses approach a bucket with feed in a three-way object-choice task when confronted with (a) an unfamiliar or (b) a familiar person in 4 different situations: (1) squatting behind the bucket, facing the horse (2) ...
Parkes RS, Weller R, Groth AM, May S, Pfau T.Visual assessment of horses' movements is subjective, affected by bias and dependent on the level of experience of the assessor. However, to date there are no data available on the ability of the human visual system to recognise (a)symmetry in moving objects. Objective: To investigate, using visual lameness assessment, the limits of human perception and the ability of experienced and nonexperienced individuals to detect asymmetry in 2 moving objects simulating hindlimb lameness in the horse. Methods: Twelve experienced individuals (equine and small animal clinicians), and 24 nonexperienced ind...
Nakamura K, Takimoto-Inose A, Hasegawa T.Humans have domesticated many kinds of animals in their history. Dogs and horses have particularly close relationships with humans as cooperative partners. However, fewer scientific studies have been conducted on cognition in horses compared to dogs. Studies have shown that horses cross-modally distinguish human facial expressions and recognize familiar people, which suggests that they also cross-modally distinguish human emotions. In the present study, we used the expectancy violation method to investigate whether horses cross-modally perceive human emotions. Horses were shown a picture of a ...
Frontiers in zoologyFebruary 11, 2017
Volume 14 8 doi: 10.1186/s12983-017-0193-1
Briefer EF, Mandel R, Maigrot AL, Briefer Freymond S, Bachmann I, Hillmann E.Non-human animals often produce different types of vocalisations in negative and positive contexts (i.e. different valence), similar to humans, in which crying is associated with negative emotions and laughter is associated with positive ones. However, some types of vocalisations (e.g. contact calls, human speech) can be produced in both negative and positive contexts, and changes in valence are only accompanied by slight structural differences. Although such acoustically graded signals associated with opposite valence have been highlighted in some species, it is not known if conspecifics disc...
Wathan J, McComb K.Sensitivity to the attentional states of others has adaptive advantages, and in social animals, attending to others is important for predator detection, as well as a pre-requisite for normal social functioning and more complex socio-cognitive abilities. Despite widespread interest in how social species perceive attention in others, studies of non-human animals have been inconclusive about the detailed cues involved. Previous work has focused on head and eye direction, overlooking the fact that many mammals have obvious and mobile ears that could act as a visual cue to attention. Here we report...
Rørvang MV, Nielsen BL, McLean AN.Vision, hearing, olfaction, taste, and touch comprise the sensory modalities of most vertebrates. With these senses, the animal receives information about its environment. How this information is organized, interpreted, and experienced is known as perception. The study of the sensory abilities of animals and their implications for behavior is central not only to ethology but also to animal welfare. Sensory ability, perception, and behavior are closely linked. Horses and humans share the five most common sensory modalities, however, their ranges and capacities differ, so that horses are unlikel...
Jensen RB, Danielsen SH, Tauson AH.Obesity is related to the development of several diseases like insulin resistance and laminitis in horses. The prevalence of obesity among mature Icelandic horses in Denmark has not been investigated previously. This study aimed to find the prevalence of obesity, to compare body condition score (BCS) based on owner perception with that of an experienced person and to correlate the BCS to body weight (BW) and morphometric measures in a group of mature Icelandic horses in Denmark. A total of 254 Icelandic horses (≥4 years; 140 geldings, 105 mares, 9 stallions) from 46 different farms were inc...
Brain lateralization is a phenomenon widely reported in the animal kingdom and sensory laterality has been shown to be an indicator of the appraisal of the stimulus valence by an individual. This can prove a useful tool to investigate how animals perceive intra- or hetero-specific signals. The human-animal relationship provides an interesting framework for testing the impact of the valence of interactions on emotional memories. In the present study, we tested whether horses could associate individual human voices with past positive or negative experiences. Both behavioural and electroencephalo...
Manyweathers J, Field H, Longnecker N, Agho K, Smith C, Taylor M.Hendra virus is a paramyxovirus that causes periodic serious disease and fatalities in horses and humans in Australia first identified in 1994. Pteropid bats (commonly known as flying-foxes) are the natural host of the virus, and the putative route of infection in horses is by ingestion or inhalation of material contaminated by flying-fox urine or other bodily fluids. Humans become infected after close contact with infected horses. Horse owners in Australia are encouraged to vaccinate their horses against Hendra virus to reduce the risk of Hendra virus infection, and to prevent potential trans...
Lesimple C, Hausberger M.Healthcare practitioners such as physicians or nurses often underestimate patients' well-being impairment (e.g., pain, anxiety) which may lead to undesirable consequences on treatment decisions. Lack of recognition/identification of signals and over-exposure are two reasons invoked, but a combination of factors may be involved. Studying human decoding of animals' expressions of emotions showed that "identification" to the subject was necessary to decode the other's internal state. In the present study we wanted to compare caretakers' reports on the prevalence of stereotypic or abnormal repetit...
Merkies K, Franzin O.Horses () have been domesticated for millennia and are regularly utilized for work, sport, and companionship. Enhanced understanding of human-horse interactions can create avenues to optimize their welfare. This review explores the current research surrounding many aspects of human-horse interactions by first highlighting the horse's sensory capabilities and how they pertain to human interactions. Evidence exists that suggests that horses can read humans in various ways through our body odours, posture, facial expressions, and attentiveness. The literature also suggests that horses are capable...
