Equine Assisted Interventions (EAIs): Methodological Considerations for Stress Assessment in Horses

The Behavioral Cost of Care: Changes in Maintenance Behavior during Equine-Assisted Interventions

This study examined human-animal symbiosis in an animal-assisted intervention through observations of animal maintenance behaviors. The rise of psychotherapy, learning, and recreation incorporating animals warrants exploration of the welfare of the animals involved in these interventions. The analysis of welfare in multispecies engagements can be discussed in terms of symbiosis. Regarding an intervention's animal provider (e.g., therapy horse) and human recipient (psychotherapy client), the balance of cost and benefit is important. Research describing human and animal interactive behavior during interventions is limited, whether focusing on client outcomes or animal welfare. The present study adapted ethological methods to study humans and animals in an equine-assisted intervention, observing equine maintenance behaviors and equid-human interactive behavior. Maintenance behaviors were recorded before, during, and after equine-assisted (psychosocial) learning sessions with youth, providing 1600 observations. Equine alertness, eating behavior, and ambulation varied significantly before, during, and after the equine-assisted sessions. Such interruptions of typical behavior are an important aspect of welfare and unit of analysis when examining symbiotic relationships. A total of 267 sequences of equid-human approach-response behavior were also recorded, indicating that human-animal interaction was predominantly from humans toward equids. Equids' dominant response to human approach was no response, followed by avoidance, while humans' dominant response to equid approach was reciprocation. The findings are discussed in terms of symbiosis and animal welfare.

Implementation of equine-assisted intervention for older adults with Alzheimer's disease residing in a nursing home: Brakes and levers

OBJECTIVE

Although research on equine-assisted intervention (EAI) for older adults is beginning to be published, no scientific study has examined the various elements that can limit or facilitate the implementation of EAI with older adults suffering from Alzheimer's disease (AD) residing in nursing homes. The aim of this study was to identify the possible brakes and levers of implementing EAI with AD patients. A focus on professional affiliation was conducted.

METHOD

The survey was posted online on 2 February 2021 via the Sphinx software. As this study was aimed at gerontology professionals working in nursing homes, they were contacted through various specialized social networks. A total of 663 people answered the survey.

RESULTS

The results indicate that for 45% of the participants, the main brake to implementing EAI is related to the institutional burden. As for the levers, 29% of the people indicated that it would mainly be beneficial due to the cognitive stimulation that EAI would provide. People who were not familiar with EAI reported more brakes to its implementation. Finally, it was observed that the caregivers were those who put forward the most levers for the implementation of EAI with AD patients living in nursing homes.

CONCLUSION

Thus, this study allows us to understand some of the reasons why nursing homes are reluctant to set up EAI. Communication on this subject is currently a lever to be developed.

IMPLICATIONS FOR PRACTICE

By highlighting the brakes and levers on the implementation of EAIs, we are able to identify suitable guidelines for developing this type of intervention in nursing homes, which could be used as a complement to nursing care to help Alzheimer's patients overcome physical or psychological health problems.

Characterizing stress during animal interaction: a focus on the human endocrine response during equine-assisted services

Repeated stresses applied to the rider may contribute to the documented physical and psychosocial outcomes from equine-assisted services. In this brief review, a summary of neuroendocrine markers of stress, including immunoglobulin A, serotonin, cortisol, progesterone, and oxytocin, is presented within the context of the physiology of stress modulation. Results are mixed with regard to the effects of these hormones on rider physiology before, during, and after equine-assisted services. However, some results from existing studies are promising with regard to the attenuation of stress. Future research should include a cross-disciplinary approach when conducting well-controlled studies with proper treatment and experimental fidelity, while also considering exogenous and endogenous factors that influence rider physiology.

Equids in Equine Assisted Services: A Scoping Review

Equid welfare in equine assisted services (EAS) is an area that has received attention, but less attention than the documentation of human outcomes in response to EAS. To safeguard the well-being of equids and minimize human risk of injury, continued research on the effects of EAS programming and participants on equids needs to occur. The aims of this systematic scoping review were to identify the approaches taken for describing and understanding equids in EAS and the methods employed in evaluating equids' responses to EAS programming, participants, or both. Literature searches were performed in relevant databases to identify titles and abstracts for screening. Fifty-three articles were identified for full-text review. Fifty-one articles met the inclusion criteria and were retained for information and data extraction. The qualitative grouping of articles by study aim resulted in four categories: 1) characterization and description of equids in EAS; 2) the acute responses of equids to EAS programming, participants, or both; 3) the effects of management practices; and 4) the chronic responses of equids to EAS programming and participants. The latter three areas are in need of more research, especially as it relates to differentiating acute and chronic effects of EAS on the equids involved. Detailed reporting of information on study design, programming and participant characteristics, equid demographics, and workload are needed to facilitate comparison among studies and permit eventual meta-analysis of studies. Multi-faceted approaches including an array of measurements as well as relevant and informative control groups or conditions are required to identify the complex effects of EAS work on equids, their welfare, well-being, and affective states.

Horses' Tactile Reactivity Differs According to the Type of Work: The Example of Equine-Assisted Intervention

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 per se. 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 that EAI horses showed higher tactile reactivity compared to EAI-RS and RS horses, both in terms of number of reactions overall, and especially when the test involved thin filaments. All horses showed high tactile reactivity when tested on the stifle, and this was particularly true for EAI horses. These differences could be related to humans' actions, as participants diagnosed with disorders brushed more the hindquarters and showed more fragmented actions. This study opens new lines of thought on the influence of EAI working activity on horses' tactile reactivity, and hence, on horses' sensory perception. Tactile reactivity outside work, may be directly (via tactile stimulations) or indirectly (via the welfare state), influenced by working conditions.

Measuring heart rate variability using a heart rate monitor in horses (Equus caballus) during groundwork

Measuring physiological parameters of stress in horses during groundwork, for example when involved in equine-assisted interventions, is important to gain insight into the stress levels of the horses. Heart rate and heart rate variability can be used as physiological indicators of stress in horses. Heart rate monitors could be easily incorporated into practice, as they are not expensive and easy to use. However, it is questionable whether heart rate monitors present accurate heart rate variability results in exercising horses, similar to electrocardiograms. The aim of this study was to determine the accuracy of heart rate monitors for the assessment of heart rate variability in horses during groundwork exercise. Simultaneous telemetric electrocardiograms (Televet) and heart rate monitor (Polar H10 transmitter and M430 receiver, Hylofit electrodes) recordings were performed on 28 horses (15 mares and 13 geldings). Results indicate that the heart rate monitor accurately determined heart rate and time-domain heart rate variability parameters when compared to electrocardiograms during both baseline and groundwork conditions. As expected, heart rate significantly increased and the heart rate variability significantly decreased during groundwork compared to baseline conditions. This indicates that the heart rate monitor can be used to accurately determine heart rate variability during groundwork.

Benefits of Equine-Assisted Therapies in People with Multiple Sclerosis: A Systematic Review

This systematic review aimed to provide an up-to-date analysis of the effects of equine-assisted therapies (EAT) in people with multiple sclerosis (PwMS). The Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) guidelines were followed to conduct this systematic review. PubMed and Web of Science databases were employed in the search, which ended in February 2022. The risk of bias analysis was performed using the Evidence Project tool. After removing duplicates, thirty-nine studies were identified. However, only ten fulfilled the inclusion criteria and were included in this systematic review. Therefore, a total of 195 PwMS, aged between 40.3 and 51.3, were included in this systematic review. EAT-based interventions had a mean length of 13.6 weeks with a session´s frequency ranging from ten to once a week. All sessions involved real horses and lasted a mean of 34.4 min. Among the included articles, four were randomized controlled trials (RCT), four did not perform randomization, and two employed a prepost design without a control group. RCTs showed positive effects on quality of life, fatigue, balance, spasticity, and gait speed. Furthermore, non-RCT showed improvements in balance, spasticity, and postural control (postural control was not assessed in RCT studies). Importantly, significant effects were only observed when the comparison group was inactive or followed usual care. Therefore, EAT is a promising and effective therapy to improve quality of life, fatigue, balance, spasticity, and gait speed in PwMS. However, since comparison groups are heterogeneous, results could vary depending on the research design. Moreover, the inclusion of noncontrolled studies (in order to have a wide perspective of the state of art) could increase the risk of bias and make the results be taken with caution.

Handlers’ Representations on Therapy Dogs’ Welfare

Simple Summary

Most research about Animal-Assisted Interventions (AAI) has focused on the benefits on human health. In contrast, very little has been made on the impact of this work on therapy dogs, although it is part of the ethics of the practice to ensure their welfare. This study aimed to contribute to the knowledge on the welfare of therapy dogs by interviewing 111 handlers through an online questionnaire. The qualitative assessment of handlers’ representations underlined that the welfare of therapy dogs is multidimensional and can be impacted by various variables. Its consideration is important for the quality and safety of the sessions, both for the dog and for the beneficiaries involved. Handlers have a central role in the welfare of their therapy dog and must be trained on stress-related behaviors. Research needs to focus on the impact of interactions on therapy dogs.

Abstract

While research on the benefits of animal-assisted interventions is beginning to build a significant body of work, studies on the well-being of therapy dogs are still in their infancy. Since handlers are the people responsible for their therapy dog’s welfare, we interviewed 111 French handlers through an online questionnaire. Our results underlined that (i) therapy dogs’ welfare is multidimensional when physical and psychological welfare, a balance between work and dog life and the settings and interactions of sessions are all taken into consideration. (ii) The response of our handlers emphasized that considering therapy dog welfare is important for the quality and safety of AAI. (iii) Three categories of risks factors were highlighted: the spatio-temporal framework (planning and environment), the interactions with beneficiaries and the handler themselves. It is particularly important that handlers talk about the negative impact of interactions with beneficiaries since they are at the heart of AAI, however there are few studies focusing on interactions as a stressor for dogs in this practice. Moreover, since there is a potential for positive bias in the handlers’ representations, it is important that they be trained to identify and manage the stress in their dogs. Future research is particularly needed on the impact of interactions during sessions on therapy dog welfare.

Nociceptive pain and anxiety in equines: Physiological and behavioral alterations

Pain and anxiety are two of the most important concerns in clinical veterinary medicine because they arise as consequences of multiple factors that can severely affect animal welfare. The aim of the present review was to provide a description and interpretation of the physiological and behavioral alterations associated with pain and anxiety in equines. To this end, we conducted an extensive review of diverse sources on the topic. The article begins by describing the neurophysiological pathway of pain, followed by a discussion of the importance of the limbic system in responses to pain and anxiety, since prolonged exposure to situations that cause stress and pain generates such physiological changes as tachycardia, tachypnea, hypertension, hyperthermia, and heart rate variability (HRV), often accompanied by altered emotional states, deficient rest, and even aggressiveness. In the long term, animals may show deficiencies in their ability to deal with changes in the environment due to alterations in the functioning of their immune, nervous, and endocrinologic systems. In conclusion, pain and anxiety directly impact the homeostasis of organisms, so it is necessary to conduct objective evaluations of both sensations using behavioral scales, like the horse grimace scale, complemented by assessments of blood biomarkers to analyze their correlation with physiological parameters: Heart rate, respiratory rate, HRV, theparasympathetic tone activity index, lactate and glucose levels, and temperature. Additional tools - infrared thermography, for example - can also be used in these efforts to improve the quality of life and welfare of horses.

Interest in Humans: Comparisons between Riding School Lesson Equids and Assisted-Intervention Equids

Simple Summary

Very little is known about the impact of equine-assisted interventions on equids’ perception of humans. Different factors can influence human–horse relationships: animal characteristics, daily interactions with the caretakers, and working and living conditions. In this study, 172 equids working in equine-assisted interventions, ‘classical’ riding school lessons, or both were submitted to a standardised human–horse relationship test in order to test if EAI had an impact on the equid reactions to humans. The possible influence of intrinsic (age, sex, type) or other extrinsic factors (housing and feeding conditions) was also considered. The results showed that the number (more than the type) of experimenter-directed behaviours varied significantly between individuals and that the activity was the most important factor of influence: Equids working in riding school lessons performed more interactive behaviours than those working in equine-assisted interventions or having mixed activity. Other factors such as daily hay quantity, the horses’ age, and sex also influenced secondarily the horse’s motivation to interact, although no interaction was found between factors. These results suggest that equine-assisted interventions do influence horses’ perception of humans outside work. Further studies are needed in order to understand the processes involved.

Abstract

Little is known about the impact of equine-assisted interventions (EAI) on equids’ perception of humans. In this study 172 equids, living in 12 riding centres, were submitted to a standardised human–horse relationship test: the motionless person test. Age, sex, type (horse/pony), housing, and feeding conditions of subjects were recorded. Overall, 17 equids worked in EAI, 95 in riding school lessons (RS), and 60 in both (EAI-RS). There were high inter-individual variations in the number of interactive behaviours directed towards the experimenter: negative binomial general linear models showed that activity was the most important factor: RS equids performed more interactive behaviours than EAI (p = 0.039) and EAI-RS (p < 0.001) equids. Daily quantity of hay appeared as the second most important factor (equids with more than 3 kg interacted more than equids with less than 3 kg, p = 0.013). Individual characteristics were also important as horses interacted more than ponies (p = 0.009), geldings more than mares (p = 0.032), and 3–15-year-old equids more than equids over 15 years (p = 0.032). However, there was no interaction between factors. The lower number of interactive behaviours of EAI equids leads to different hypotheses—namely, selection on temperament, specific training, or compromised welfare (apathy). In any case, our results raised new lines of questions on EAI.

Horse Behavior towards Familiar and Unfamiliar Humans: Implications for Equine-Assisted Services

While human benefits of animal-assisted therapy programs have been documented, relatively little research has been conducted on behavioral factors that predict a successful equine-assisted services (EAS) horse. This study compares the behavior of experienced and non-experienced EAS horses as well as horses selected for future EAS work in a series of sociability and temperament tests. No significant differences were found between experienced and non-experienced horses in the sociability measures or for most of the temperament tests; however, significant differences were found between groups in the brushing test, with non-experienced horses showing more affiliative behaviors towards the familiar handler and unfamiliar persons. No significant differences were found between selected and non-selected horses in the temperament tests. However, non-selected horses were found to show significantly more affiliative behaviors towards a familiar person during a sociability test compared with selected horses. These findings suggest that the social behavior and temperament of EAS horses may not be significantly different from other available horses not selected for EAS work. Instead, these decisions may primarily reflect subjective impressions of fit. Interestingly, on measures where significant differences were identified, the horses not actively engaged in or selected for therapy were the ones that showed greater affiliative responses to familiar and unfamiliar humans. Reasons for why this may be, as well as future directions in EAS selection, are discussed.

Detecting Welfare in a Non-Verbal Species: Social/Cultural Biases and Difficulties in Horse Welfare Assessment

Simple Summary

There is a paradox about the welfare of horses in the domestic situation: on the one hand, horses are beloved partners for most owners, but on the other hand, scientific studies are converging to show that there is a high prevalence of welfare problems. There seems to be a mismatch between theoretical knowledge and field applications. In this review, we aim at disentangling the possible factors explaining such a paradox. Among them, we consider the impact of anthropomorphic and cultural biases, popular beliefs, but also overexposure to horses with compromised welfare state, which can change owners’ representation of what is a “normal” horse, on the undervaluation of horse welfare state. We suggest that, rather than simply having knowledge on what should be done, identifying the horse welfare state using validated animal-based indicators is essential to identify and promote best practices.

Abstract

Horses were domesticated for more than 5000 years and have been one of the most emblematic species living alongside humans. This long-shared history would suggest that horses are well known and well understood, but scientific data raise many concerns about the welfare state of most domestic horses suggesting that many aspects have been largely misunderstood. In the present review, we will examine some of the possible human factors that may explain the huge prevalence of welfare problems, despite horses being of special importance to humans. First of all, as horses are non-verbal, current management practices rely upon what one thinks is good for them, which opens the way to subjective interpretations and projections, based on one’s own subjective experience but probably still more on cultural/social norms and influences, traditions and beliefs. The lack of recognition, identification, or even the misinterpretation of signals are other potential reasons for welfare issues. Lastly, the over-exposure to animals with expressions of compromised welfare may lead to lower sensitivity of owners/professionals. That is why we lastly suggest that instead of simply providing information on what to do, we should promote validated visible indicators that leave less room for personal interpretation.

Equine-Assisted Interventions (EAIs) for Children with Autism Spectrum Disorders (ASD): Behavioural and Physiological Indices of Stress in Domestic Horses (Equus caballus) during Riding Sessions

Equine-assisted interventions (EAIs) are well-known complementary practices combining physical activity with emotional/cognitive stimulation. They are especially suited for children with autism spectrum disorders (ASD) who need a high degree of physical and psychological enrichment. Even though EAIs have become a common practice, stress responses in horses interacting with individuals that can manifest inappropriate behaviours, such as ASD children, have not been thoroughly investigated. Our multicentre study aimed to investigate behavioural and physiological indices of stress in horses involved in EAI standardised sessions with children with ASD compared to typically developing (TD) children. A controlled within-subject design with repeated measurements involving 19 horses and 38 children was adopted. Stress-related behaviours, heart rate, heart rate variability, and eye temperature were recorded during the riding sessions. Moreover, blood samples were collected from horses before and after each session to monitor changes in blood adrenocorticotropic hormone (ACTH), cortisol, and catecholamines. Results indicate that, in general, stress responses in horses involved in EAIs did not differ as a function of the horse being ridden by children with ASD or TD. A lower sympathetic tone in horses involved in ASD sessions was found, while in the mounting and dismounting phases, horses displayed behavioural signs of stress, independently from children's behaviour. We conclude that professionals working in EAI should increase their awareness of animal welfare and refine riding practices, taking into account horse's needs.

Ethological and Physiological Parameters Assessment in Donkeys Used in Animal Assisted Interventions

BACKGROUND

Few studies have been performed to identify objective indicators for the selection of therapeutic donkeys or to assess their welfare during animal-assisted interventions (AAIs) Objective: This study aimed to evaluate the response to the ethological test and the modifications of physiological parameters in donkeys subjected to AAI sessions.

METHODS

Thirteen donkeys were subjected to a behavioral evaluation during an AAI session. Heart rate, heart rate variability, and root mean square of successive difference values were detected.

RESULTS

Statistically significant changes in the tested parameters were observed during AAI sessions.

CONCLUSIONS

In donkeys, there was a neurovegetative involvement during AAI sessions. Our data give a contribution to the evaluation of donkey welfare during AAIs.

The influence of human interaction on guinea pigs: Behavioral and thermographic changes during animal-assisted therapy

Guinea pigs are often involved in animal-assisted therapy (AAT) but there is little knowledge about the effects of human contact on guinea pigs involved in AAT. The aim of this study was to investigate effects of availability of a retreat, presence of conspecifics, prior experience with AAT, and human interaction on indicators of welfare in guinea pigs involved in AAT. Guinea pigs of both sexes and different ages (n=20) were assigned to a randomized, controlled within-subject trial with repeated measurements. Each guinea pig was tested in four settings: (I) therapy with retreat possibility with conspecifics, (II) therapy with retreat possibility without conspecifics, (III) therapy without retreat possibility, and (IV) setting without human interaction. We measured changes in eye temperature, as a proxy to infer stress levels, at 5-s intervals with a thermographic camera. All sessions were video recorded and the guinea pigs' behavior was coded using continuous recording and focal animal sampling. For the statistical analysis we used generalized linear mixed models, with therapy setting as a fixed effect and individual guinea pig as a random effect. We observed a temperature increase relative to baseline in settings (I) therapy with retreat with conspecifics present and (III) therapy without retreat. The percentage of time a guinea pig was petted was positively correlated with a rise in the eye temperature independent of the setting. Time spent eating was reduced in all therapy settings (I-III) compared to the setting without HAI (human animal interaction) (IV). In the setting with retreat (I), guinea pigs showed more active behaviors such as locomotive behavior or startling compared to the setting without retreat (III) and the setting without HAI (IV). When no retreat was available (III), they showed more passive behaviors, such as standing still or freezing compared to therapy with retreat (I). Based on our results we identified the behaviors "reduced eating", "increased startle" and "increased freezing" as indicators of an increased stress level. Petting the guinea pigs was correlated with a rise in the eye temperature and might be a factor which can cause stress. Our results support the suggestion that guinea pigs involved in AAT should have a retreat possibility, should have access to conspecifics, and should be given time to adapt to a new setting. In this way, stress might be reduced.

Equine-Assisted Intervention to Improve Perceived Value of Everyday Occupations and Quality of Life in People with Lifelong Neurological Disorders: A Prospective Controlled Study

People with neurological disorders suffer from poor mobility, poor balance, fatigue, isolation and monotonous everyday activities. Studies show that equine-assisted interventions can improve their mobility and balance, but could these kinds of interventions also increase participants’ activity repertoire and self-assessed health, and reduce their fatigue? The study was conducted as a prospective, controlled study with three cohorts followed for one year: intervention group (n = 14), control group Passive (n = 29), and control group Active (n = 147). Participants in the study were affected by neurological disease or injury that limited their opportunities for an active everyday life. The intervention group lacked regular activities outside the home before the intervention, which consisted of riding once a week, led by a certified therapist. Control group Passive lacked regular activities outside the home, while control group Active had several activities outside the home per week. Primary outcome measures were activity repertoire measured with Occupational Value Assessment questionnaire. Secondary outcome measures were global self-assessed health measured with EuroQol-VAS and fatigue measured with Shirom-Melamed Burnout Questionnaire. The intervention group’s activity repertoire and self-assessed health increased significantly compared to both baseline and the control groups. Equine-assisted interventions could help to improve the perceived value of everyday occupations and quality of life, as well as break isolation and increase the activity repertoire of people with neurological disorders.

Emotional Transfer in Human-Horse Interaction: New Perspectives on Equine Assisted Interventions

Simple Summary

Equine assisted interventions (EAIs) represent an emerging field of animal assisted interventions (AAIs), employing horses in a wide variety of activities with humans. Based on the socio-emotional competences of this species, which evolved sophisticated communicative skills to interrelate with humans, we here hypothesized the occurrence of an interspecific emotional transfer during interventions. The emotional transfer hypothesis suggests a mutual coordination of emotional states of humans and horses, which are going through a coupling process during the interaction. Even though this mechanism is supported by few existing studies on human-horse emotional fine-tuning, it could play a key role in EAIs. We moreover propose to measure this coordination through monitoring physiological variables with a novel multidisciplinary method. In the future, having an insight on emotional states of animals involved in AAIs could be useful to ameliorate the wellbeing of both animal and human subjects and to better standardize operational strategies.

Abstract

Equine assisted interventions (EAIs) include all therapeutic interventions aimed at improving human wellbeing through the involvement of horses. Due to the prominent emotional involvement traditionally characterizing their relation with humans, horses developed sophisticated communicative skills, which fostered their ability to respond to human emotional states. In this review, we hypothesize that the proximate causation of successful interventions could be human–animal mutual coordination, through which the subjects bodily and, most importantly, emotionally come into contact. We propose that detecting emotions of other individuals and developing the capacity to fine-tune one’s own emotional states accordingly (emotional transfer mechanism), could represent the key engine triggering the positive effects of EAIs. We provide a comprehensive analysis of horses’ socio-emotional competences according to recent literature and we propose a multidisciplinary approach to investigate this inter-specific match. By considering human and horse as a unique coupling system during the interaction, it would be possible to objectively measure the degree of coordination through the analysis of physiological variables of both human and animal. Merging the state of art on human–horse relationship with the application of novel methodologies, could help to improve standardized protocols for animal assisted interventions, with particular regard to the emotional states of subjects involved.

Do Animals Perceive Human Developmental Disabilities? Guinea Pigs' Behaviour with Children with Autism Spectrum Disorders and Children with Typical Development. A Pilot Study

Some cues used by humans and animals during human-animal interactions may have significant effects, modulating these interactions (e.g., gaze direction, heart rate). This study aimed to determine whether an animal in human-animal interactions is capable of "perceiving" its human partner's potential developmental "disabilities". To test this hypothesis, we studied guinea pigs (GP) behaviours in the presence of 44 6-to-12-year-old children with either typical development (TD children) or with autism spectrum disorders (ASD children). Thus, we recorded the GP behaviours during the entire session (to establish their time budget) and focused in particular on the onset and end of physical interactions. The GP behaviours (e.g., feeding, resting, self-grooming, exploring) were not significantly different between the two groups of children during the whole session. GP behaviours in the presence of children differed slightly when encountering ASD children versus TD children: more positive behaviours toward ASD children at the onset, more feeding and resting in the presence of TD children toward the end of an interaction. TD children showed longer-lasting interactions. One could explain this by GP curiosity toward ASD children behaviours (e.g., no marked behaviours such as attempts to touch), whereas GPs seemed calmer at the end with TD children (i.e., interacting with ASD children may be a little stressful). This partly gave support to our study's hypothesis. GPs seemed to perceive developmental disabilities during a first encounter with children and to adjust their behaviours to that of children. We discuss the issues of animal training, animals' well-being and acute stress, whether they are pets or used in animal-assisted interventions. Further studies (on pets or animal-assisted interventions) are warranted.

A One Health Research Framework for Animal-Assisted Interventions

BACKGROUND

The integration of animals into healthcare, referred to as animal-assisted intervention, is a rapidly growing research field and was previously related to One Health. However, the assessment of synergistic effects of animal-assisted interventions (AAI) has been poorly addressed to date.

METHOD

We discuss experiences in integrated human and animal assessments in AAI and provide a methodical framework for One Health approaches in AAI research. We propose theoretical consideration of an integrated human and animal health assessment, as well as the use of such an integrated approach in research. Based on the existing research, we argue that, for a deeper understanding of AAI mechanisms, parallel research designs are needed.

RESULTS AND CONCLUSION

Our paper shows that a One Health study design is necessary to ensure that a tradeoff in health of animals is prevented and that an added value, or synergistic benefit, can be achieved on both sides during animal-assisted interventions.

Physiological outcomes of calming behaviors support the resilience hypothesis in horses

To manage a stressful stimulus animals react both behaviorally and physiologically to restore the homeostasis. In stable horses, a stressful stimulus can be represented by social separation, riding discomfort or the presence of novel objects in their environment. Although Heart Rate Variability is a common indicator of stress levels in horses, the behavioral mechanisms concurrently occurring under stressful conditions are still unknown. The sudden inflation of a balloon was administered to 33 horses. Video-recording of self-directed behaviors (snore, vacuum chewing, snort, head/body shaking) and monitoring of heart activity (HR and SDRR) were conducted for five minutes before (Pre-test) and after the stimulus administration (Stress-test). During the Stress-test, only snore and vacuum chewing increased and a significant increase was also recorded in both HR and SDRR. Moreover, the snore variation between the two conditions showed a significant correlation with the variation of both HR and SDRR. With the snore acting as stress-releasing behavior to restore basal condition, the homeostasis recovered via the enactment of such behavior could be physiologically expressed by an increasing vagal activity. Hence, the capacity to maintain homeostasis (resilience) could correspond to a prevalence of parasympathetic control on heart activity, intervening when certain behaviors are performed.

Describing the Use of Animals in Animal-Assisted Intervention Research

Currently, there has been growing attention to animal welfare in animal-assisted interventions (AAI). However, there is a lack of scrutiny regarding what steps to take to ensure animal wellbeing during AAI research. The Institutional Animal Care and Use Committee (IACUC) reviews, monitors, and approves all research involving animal subjects in order to ensure an animal's ethical and humane treatment. However, AAI publications rarely report IACUC approval. The purpose of this critical review was to determine the frequency of IACUC approval and to report the descriptions of animal use in AAI research publications. In the 139 articles reviewed, 14 (10%) studies reported attaining IACUC approval; 4/139 (3%) reported an adverse outcome on at least one animal used in the study. The publications inconsistently reported the training or certification and veterinary care of the animals. Lacking IACUC approval in AAI studies indicates that the field underutilizes this method of monitoring animal health and welfare. The IACUC should assess, approve, and monitor research protocols involving animals prior to conducting every study to safeguard AAI animal welfare.