Towards a Naturalistic Animal Model of Depression? A Study on Horses

BackgroundRecent reviews question current animal models of depression and emphasise the need for ethological models of mood disorders based on animals living under natural conditions. Domestic horses encounter chronic stress, including potential stress at work, which can induce behavioural disorders (e.g. “apathy”). Our pioneering study evaluated the potential of domestic horses in their usual environment to become an ethological model of depression by testing this models’ face validity (i.e. behavioural similarity with descriptions of human depressive states).Methodology/Principal FindingsWe observed the spontaneous behaviour of 59 working horses in their home environment, focusing on immobility bouts of apparent unresponsiveness when horses displayed an atypical posture (termed withdrawn hereafter), evaluated their responsiveness to their environment and their anxiety levels, and analysed cortisol levels. Twenty-four percent of the horses presented the withdrawn posture, also characterized by gaze, head and ears fixity, a profile that suggests a spontaneous expression of “behavioural despair”. When compared with control “non-withdrawn” horses from the same stable, withdrawn horses appeared more indifferent to environmental stimuli in their home environment but reacted more emotionally in more challenging situations. They exhibited lower plasma cortisol levels. Withdrawn horses all belonged to the same breed and females were over-represented.Conclusions/SignificanceHorse might be a useful potential candidate for an animal model of depression. Face validity of this model appeared good, and potential genetic input and high prevalence of these disorders in females add to the convergence. At a time when current animal models of depression are questioned and the need for novel models is expressed, this study suggests that novel models and biomarkers could emerge from ethological approaches in home environment

Lower bound of Schr{\"o}dinger operators on Riemannian manifolds

We show that a weighted manifold which admits a relative Faber Krahn inequality admits the Fefferman Phong inequality V $\psi$, $\psi$ $\le$ CV $\psi$ 2 , with the constant depending on a Morrey norm of V , and we deduce from it a condition for a L 2 Hardy inequality to holds, as well as conditions for Schr{\"o}dinger operators to be positive. We also obtain an estimate on the bottom of the spectrum for Schr{\"o}dinger operators

De la difficulté à être reconnus « capables » et « compétents » : des adolescents et jeunes adultes désignés handicapés mentaux en quête d’autonomie

International audienceDepuis deux décennies, le législateur français s'attache à promouvoir l'autonomie des personnes en situation de handicap en leur permettant, notamment, d'accroitre leur pouvoir d'agir sur leur environnement par autodétermination. A cet égard, nombre de dispositifs dont elles sont la cible témoignent de cette volonté de soutenir l'autonomie des personnes désignées handicapées mentales définies traditionnellement en termes de dépendance et d'incapacités. À partir d'une enquête ethnographique, cette contribution examine les dynamiques paradoxales qui traversent la politique publique d'inclusion, à visée émancipatrice, au sein d'un dispositif Ulis. Elle décrit la difficulté que rencontre un groupe d'adolescents et jeunes adultes désignés handicapés mentaux scolarisés dans un lycée professionnel à être reconnu « capable » et à s'inscrire dans un processus d'autonomisation. L'analyse des expériences vécues par ces jeunes montre qu'ils doivent faire face à un soupçon d'incompétence et à un processus d'infantilisation qui tiennent moins à leurs incapacités réelles qu'à la manière dont ils sont catégorisés, en tant que jeunes désignés « handicapés mentaux »

Effects of long-term exposure to an electronic containment system on the behaviour and welfare of domestic cats

Free-roaming cats are exposed to a variety of risks, including involvement in road traffic accidents. One way of mitigating these risks is to contain cats, for example using an electronic boundary fence system that delivers an electric ‘correction’ via a collar if a cat ignores a warning cue and attempts to cross the boundary. However, concerns have been expressed over the welfare impact of such systems. Our aim was to determine if long-term exposure to an electronic containment system was associated with reduced cat welfare. We compared 46 owned domestic cats: 23 cats that had been contained by an electronic containment system for more than 12 months (AF group); and 23 cats with no containment system that were able to roam more widely (C group). We assessed the cats’ behavioural responses and welfare via four behavioural tests (unfamiliar person test; novel object test; sudden noise test; cognitive bias test) and an owner questionnaire. In the unfamiliar person test, C group lip-licked more than the AF group, whilst the AF group looked at, explored and interacted more with the unfamiliar person than C group. In the novel object test, the AF group looked at and explored the object more than C group. No significant differences were found between AF and C groups for the sudden noise or cognitive bias tests. Regarding the questionnaire, C group owners thought their cats showed more irritable behaviour and AF owners thought that their cats toileted inappropriately more often than C owners. Overall, AF cats were less neophobic than C cats and there was no evidence of significant differences between the populations in general affective state. These findings indicate that an electronic boundary fence with clear pre-warning cues does not impair the long term quality of life of cat

How Useful Are Existing Protocols in the Quick Assessment of the Welfare of Semi-Feral Horses? Pilot Study on Konik Polski Horses Living in the Forest Sanctuary

Scientifically validated and standardised methods for the evaluation of the welfare of free-living horses are urgently needed by both the owners and managers of these populations and those responsible for implementing national welfare legislation. The aim of the study was to test the feasibility and usefulness of two welfare protocols that could be applied to semi-feral populations: a prototype of welfare assessment template (WAT) for Carneddau semi-feral ponies and the IFCE/INRAE Horse Welfare Protocol. Additionally, the body condition scale designed by Henneke (BCS-H) was employed. The study took place in July/August 2022 and April 2023 to evaluate the welfare of a pilot population of nineteen semi-feral Konik polski horses. The horses scored high or satisfactory under indicators across both protocols; only body condition scores were significantly lower in early spring (BCS-WAT: 1.11 ± 0.57; BCS-H: 3.84 ± 1.17) than in the summer (BCS-WAT: 1.58 ± 0.61; BCS-H: 5.63 ± 1.01). Our study confirmed the feasibility of utilising most of the WAT and IFCE/INRAE welfare indicators in semi-feral horses. Some adaptations, such as considering validation of scales, positive welfare indicators and animals’ free-choice of conditions, have been suggested for future in-field application

Multiple handlers, several owner changes and short relationship lengths affect horses’ responses to novel object tests

Peer reviewe

The predictive value of early behavioural assessments in pet dogs: a longitudinal study from neonates to adults

Studies on behavioural development in domestic dogs are of relevance for matching puppies with the right families, identifying predispositions for behavioural problems at an early stage, and predicting suitability for service dog work, police or military service. The literature is, however, inconsistent regarding the predictive value of tests performed during the socialisation period. Additionally, some practitioners use tests with neonates to complement later assessments for selecting puppies as working dogs, but these have not been validated. We here present longitudinal data on a cohort of Border collies, followed up from neonate age until adulthood. A neonate test was conducted with 99 Border collie puppies aged 2–10 days to assess activity, vocalisations when isolated and sucking force. At the age of 40–50 days, 134 puppies (including 93 tested as neonates) were tested in a puppy test at their breeders' homes. All dogs were adopted as pet dogs and 50 of them participated in a behavioural test at the age of 1.5 to 2 years with their owners. Linear mixed models found little correspondence between individuals' behaviour in the neonate, puppy and adult test. Exploratory activity was the only behaviour that was significantly correlated between the puppy and the adult test. We conclude that the predictive validity of early tests for predicting specific behavioural traits in adult pet dogs is limited

Emotional contagion of fear and joy from humans to horses using a combination of facial and vocal cues

Emotional contagion, the emotional state-matching of two individuals, has been documented in various species. Recent findings suggest emotional contagion could also take place between humans and domestic mammals. However, the range of targeted animal species and human emotions that have been studied is still limited, and the methodology to investigate emotional contagion in this context is not fully established. This study examined emotional contagion of fear and joy from humans to horses by measuring physiological (heart rate, infrared thermography) and behavioral responses (posture, laterality bias, facial expressions) to videos of human fear, joy, or neutral emotions. Horses (n = 45) exhibited higher heart rates and ear movements during the fear and joy videos compared to the neutral ones, suggesting heightened arousal. During fear videos, they showed a greater increase in eye temperature than during joy or neutral videos, and maintained an alert posture for longer than during neutral videos, expressing specific facial expressions including inner brow raising and blowing. During joy videos, they showed a higher right eye preference (indicating a higher left-hemisphere bias) than during neutral videos, suggesting a more positive emotional valence. These findings suggest that human facial and vocal cues of fear and joy trigger emotional contagion in horses, which may influence the human-horse relationship

Le mal-être active les gènes codant pour l'inflammation

Les chevaux agressifs ne sont pas simplement des chevaux mal éduqués ou caractériels. Cette agressivité peut révéler des souffrances physiques et un état de mal-être qui peuvent être profonds. Cet état de mal-être va jusqu’à modifier l’expression de certains de leurs gènes : ceux impliqués dans la réponse immunitaire et au stress, et la mort cellulaire programmée. Cela montre à quel point ce trouble ne doit pas être pris à la légère. Les chevaux qui présentent un trouble agressif doivent être pris en charge afin de faire évoluer leurs conditions de vie et de travail vers une meilleure prise en compte de leur bien-être

Priming for welfare: gut microbiota is associated with equitation conditions and behavior in horse athletes

We simultaneously measured the fecal microbiota and multiple environmental and host-related variables in a cohort of 185 healthy horses reared in similar conditions during a period of eight months. The pattern of rare bacteria varied from host to host and was largely different between two time points. Among a suite of variables examined, equitation factors were highly associated with the gut microbiota variability, evoking a relationship between gut microbiota and high levels of physical and mental stressors. Behavioral indicators that pointed toward a compromised welfare state (e.g. stereotypies, hypervigilance and aggressiveness) were also associated with the gut microbiota, reinforcing the notion for the existence of the microbiota-gut-brain axis. These observations were consistent with the microbiability of behaviour traits (> 15%), illustrating the importance of gut microbial composition to animal behaviour. As more elite athletes suffer from stress, targeting the microbiota offers a new opportunity to investigate the bidirectional interactions within the brain gut microbiota axis.info:eu-repo/semantics/publishedVersio