Stress in horses refers to the physiological and behavioral responses of equines to various stressors, including environmental changes, social dynamics, and physical exertion. These responses can manifest through alterations in heart rate, cortisol levels, and behavior, among other indicators. Stress can affect a horse's overall health, performance, and welfare, making it a significant area of study in equine research. This topic encompasses research on identifying stressors, measuring stress responses, and understanding the implications of stress on equine health and behavior. This page compiles peer-reviewed research studies and scholarly articles that explore the mechanisms, effects, and management of stress in horses.
den Boer JC, Klip H, Blonk A, Lenselink M, Kaijdoe SPT, Tielkes M, van Zandbeek A, Bres G, Herinx M, Staal WG, Rommelse N.For people with autism spectrum disorder (ASD), daily life can be highly stressful with many unpredictable events that can evoke emotion dysregulation (ED): a strong difficulty with appropriately negative affect regulation. For some of the patients with ASD, treatment as usual does not prove to be effective for ED. They may be at risk of life-long impairment, development of other disorders and loss of motivation for most regular forms of therapy. A highly promising method that may prove effective for therapy-resistant individuals with ASD is Psychotherapy incorporating horses (PIH). PIH uses t...
Arrigo F, Aragona F, Faggio C, Giudice E, Giannetto C, Piccione G, Rizzo M, Arfuso F.The aim of this study was to assess the changes of pro-inflammatory interleukins in 10 horses subjected to road transport practices (distance of 150 km) from the training site (Messina, Sicily) to the competition centre in Syracuse (Sicily). Blood sampling and interleukins analysis were performed during a round trip transportation (transport 1 and transport 2). In particular, blood samples were collected before the transport took place (Pre), five minutes later (Post) and one hour later (Post 1 h), for each transport, in order to assess the serum concentration of IL-1α, IL-1β, IL-2 and IL-...
Medina B AL, Faleiros RR, Martínez A JR.Equine Gastric Ulcer Syndrome (EGUS) occurs with variable prevalence in horses, donkeys, and mules. Due to the particularities of the mucous membranes, the syndrome is made up of Squamous Gastric Disease (ESGD) and Glandular Gastric Disease (EGGD). Given the multifactorial nature and multiple classification systems of the syndrome, significant differences have been reported between prevalence studies performed ante mortem, which are even more remarkable when compared with postmortem evaluations. This study aimed to determine the presence and grade of squamous gastric disease in horses, donkeys...
Aragona F, Rizzo M, Arfuso F, Acri G, Fazio F, Piccione G, Giannetto C.The aim of the present study was to investigate eye temperature modifications after road transport in athletic horses habituated to travel. Eight adult Italian saddle horses traveled 100 km and, two weeks later, 300 km. Eye temperature (ET), rectal temperature (RT) and serum cortisol concentration were assessed before (T1), after (T2) and 60 min (T3) after the road transport. ET was evaluated with infrared thermography (IRT) in three regions of interest: EL1 (medial canthus), EL2 (central cornea) and EL3 (lateral canthus). Two-way analysis of variance (ANOVA) for repeated measures showed stati...
Burrell KL, Burford JH, England GCW, Freeman SL.The survival of horses diagnosed with critical colic (requiring referral or euthanasia) relies on rapid and effective decision-making by the owner and veterinary practitioner. Objective: To explore UK horse owners' and veterinary practitioners' experiences of decision-making for critical cases of equine colic. Methods: Qualitative study using a phenomenological approach. Methods: Individual, semi-structured telephone interviews were conducted with 14 horse owners and 13 veterinary practitioners (vets) who had experienced a critical decision (referral or euthanasia) for a horse with colic. A pu...
Animal welfare has become an increasingly important concern regarding equids working as carriage animals. In the present study, the changes in the markers of stress and inflammatory responses as a result of the work performed by tourism carriage horses under real working conditions in Sicily (Italy) were investigated. Twenty-two Standardbreds performed a normal working day in the carriage tourism business during the months of May, June and July 2022, consisting of one day of work for each month. Blood samples were collected in the stables at rest before the tour route (Pre; 07.00 AM) and withi...
Huangsaksri O, Wonghanchao T, Sanigavatee K, Poochipakorn C, Chanda M.Heart rate variability (HRV) is a frequently used indicator of autonomic responses to various stimuli in horses. This study aimed to investigate HRV variables in horses undergoing cold (n = 25) or hot (n = 26) shoeing. Multiple HRV variables were measured and compared between horses undergoing cold and hot shoeing, including the time domain, frequency domain, and nonlinear variables pre-shoeing, during shoeing, and at 30-minute intervals for 120 minutes post-shoeing. The shoeing method interacted with time to change the HRV variables standard deviation of RR intervals (SDNN), root mean square ...
Aragona F, Arfuso F, Rizzo M, Fazio F, Acri G, Piccione G, Giannetto C.This study aimed to evaluate changes in body temperature in athletic horses during two different road transport distances. Six Italian Saddle horses were subjected to a 100 and 300 km transport during different times of day (am and pm). Rectal and cutaneous temperatures were recorded before (T0), immediately (following 5 min- T1) and 1 hour (T2) after transport by means of a rectal digital thermometer and a thermal infrared camera (FLIR T440) respectively, for the evaluation of left and right side of four body regions: jugular, shoulder, croup and inner thigh. There were no differences between...
Huangsaksri O, Sanigavatee K, Poochipakorn C, Wonghanchao T, Yalong M, Thongcham K, Srirattanamongkol C, Pornkittiwattanakul S, Sittiananwong T....Horses participating in endurance events encounter enormous physical challenges. Heart rate (HR) and heart rate variability (HRV) have been reported before and after endurance rides, but these have not been determined during the rides. Moreover, the modulation in HRV and haematology in horses with different ride results (completed a course or disqualified due to irregular gait) have not been elucidated. Therefore, this study aimed to investigate changes in HR, HRV, and haematological parameters during novice endurance rides and to compare these parameters between horses that successfully compl...
Bazzano M, Marchegiani A, La Gualana F, Petriti B, Spaterna A, Laus F.Horse welfare is the product of multiple factors, including behavioral and physiological adjustments to cope with stressful situation regarding environment and housing condition. Collectively, it is supposed that a horse kept in the wild has a lower level of stress than other housing system, and the aim of the present study was to investigate the level of stress in domestic horses reared in the wild and then moved to human controlled housing, through saliva analysis. Twelve clinically healthy Catria (Italian local breed) mares, usually reared in the wild, were moved into collective paddocks fo...
Sanigavatee K, Poochipakorn C, Huangsaksri O, Wonghanchao T, Yalong M, Poungpuk K, Thanaudom K, Chanda M.Strenuous exercise in traditional polo matches creates enormous stress on horses. Hematological and physiological measures may vary across different field-play positions. This study aimed to investigate the effort intensity and the impact of exertion on hematology and heart rate variability (HRV) in polo ponies with different positions. Thirty-two ponies, divided equally into eight teams, were studied. Each comprises forwards (number 1), midfielders (numbers 2 and 3), and defenders (number 4). Team pairs played the first chukka in four low-goal polo matches. Percent maximum heart rate (%HRmax)...
Sanigavatee K, Poochipakorn C, Huangsaksri O, Wonghanchao T, Rodkruta N, Chanprame S, Wiwatwongwana T, Chanda M.Athletic horses are usually retired from equestrian competition at an advanced age. Aged horses may then continue to have regular exercise or are sedentary. The comparison of autonomic regulation between sedentary aged horses (SAH) and trained aged horses (TAH) after retirement remains unpublished. This study compared daily heart rate (HR) and heart rate variability between 11 SAH and 11 TAH over 22 hours (07.00 h to 05.00 h on an alternate day) and during the day and night. An increase in mean beat-to-beat (RR) intervals (p < 0.01-0.0001) and parasympathetic nervous system (PNS) index (p &...
Gibb Z, Aitken RJ, Sheridan AR, Holt B, Waugh S, Swegen A.The in vitro storage of stallion spermatozoa for use in artificial insemination leads to oxidative stress and imbalances in calcium homeostasis that trigger the formation of the mitochondrial permeability transition pore (mPTP), resulting in premature cell death. However, little is understood about the dynamics and the role of mPTP formation in mammalian spermatozoa. Here, we identify an important role for mPTP in stallion sperm Ca2+ homeostasis. We show that stallion spermatozoa do not exhibit "classical" features of mPTP; specifically, they are resistant to cyclosporin A-mediated inhibition...
Rişvanlı A, Şen İ, Canuzakov K, Tülöbayev A, Taş A, Saklykov R, Ceylan N, Türkçapar Ü, Alimov U, Kazakbayeva A, Cunuşova A, Uulu NA....The aim of this study was to examine variations in stress, metabolic, and physiological parameters of horses used in the traditional equestrian team sport of Kök-Börü in relation to winning and losing outcomes. Methods: To accomplish this, blood samples were taken from horses on four different teams who participated in two separate games, both before and after game. These samples were used to measure levels of cortisol, ACTH, beta-endorphin, adrenaline, noradrenaline, triiodothyronine (T3), and thyroxine (T4) via species-specific commercial ELISA kits. The autoanalyzer tested biochemical an...
May A, Gerhards H, Wollanke B.During hospitalization horses may develop gastrointestinal conditions triggered by a stress-associated weak local immune system. The prospective, clinical trial was conducted to find out whether fecal immunoglobulin A (IgA) concentrations could be determined in hospitalized horses and how they changed during hospitalization and in response to various stressors. Samples were obtained from 110 horses and a control group (n = 14). At arrival in the hospital, horses were categorized into pain grades (1-5), and elective versus strenuous surgery (> 2 hours, traumatic and emergency procedures). Feces...
Ayodele BA, Pagel CN, Mackie EJ, Armour F, Yamada S, Zahra P, Courtman N, Whitton RC, Hitchens PL.Musculoskeletal injuries (MSI) are common in racehorses and have been of increasing concern in horses travelling internationally to compete. Understanding the differences in bone turnover between local horses and international horses following long-distance air transportation may inform MSI prevention strategies. Objective: To understand the differences in bone turnover markers and risk of MSI between local horses and international horses following long-distance air transportation. Methods: Prospective cohort. Methods: The concentrations of bone turnover markers (OCN and CTXI), markers of stre...
Whitfield-Cargile CM, Chung HC, Coleman MC, Cohen ND, Chamoun-Emanuelli AM, Ivanov I, Goldsby JS, Davidson LA, Gaynanova I, Ni Y, Chapkin RS.The equine gastrointestinal (GI) microbiome has been described in the context of various diseases. The observed changes, however, have not been linked to host function and therefore it remains unclear how specific changes in the microbiome alter cellular and molecular pathways within the GI tract. Further, non-invasive techniques to examine the host gene expression profile of the GI mucosa have been described in horses but not evaluated in response to interventions. Therefore, the objectives of our study were to (1) profile gene expression and metabolomic changes in an equine model of non-ster...
Shakeel M, Choi Y, Yoon M.Cryptorchidism affects spermatogenesis and testis development, often resulting in stallion subfertility/infertility. This study aims to identify the specific germ cells impacted by cryptorchism in stallions. In a previous study, we found that PGP9.5 and VASA are molecular markers expressed in different germ cells within stallions. Herein, we assessed the heat stress-induced response of spermatogonial stem cells (SSCs) in the seminiferous tubules (ST) of cryptorchid stallion testes (CST) and normal stallion testes (NST). This goal was accomplished by comparing PGP9.5 and VASA expression pattern...
Meissner JM, Chmielińska A, Ofri R, Cisło-Sankowska A, Marycz K.Corneal ulcers, characterized by severe inflammation of the cornea, can lead to serious, debilitating complications and may be vision-threatening for horses. In this study, we aimed to investigate the role of endoplasmic reticulum (ER) stress in corneal stem progenitor cell (CSSC) dysfunction and explore the potential of equine adipose-derived stromal stem cell (ASC)-derived extracellular vesicles (EVs) to improve corneal wound healing. We showed that CSSCs expressed high levels of CD44, CD45, and CD90 surface markers, indicating their stemness. Supplementation of the ER-stress-inducer tunicam...
Zhang X, Geng A, Cao D, Dugarjaviin M. Horses are susceptible to oxidative stress during strenuous endurance exercise, leading to muscle fatigue and damage. Mulberry leaf flavonoids (MLFs) possess significant antioxidant properties. However, the antioxidant efficacy of MLFs can be influenced by the extraction process, and their impact on HO-induced oxidative stress in equine skeletal muscle satellite cells (ESMCs) remains unexplored. Our study employed three extraction methods to obtain MLFs: ultrasound-assisted extraction (CEP), purification with AB-8 macroporous resin (RP), and n-butanol extraction (NB-EP). We assessed the prot...
Faulkner JE, Joostens Z, Broeckx BJG, Hauspie S, Mariën T, Vanderperren K.Injuries of the sagittal groove of the proximal phalanx (P1) in equine athletes are considered to predominantly occur due to chronic bone stress overload. Objective: To describe the range of abnormalities that is present in the sagittal groove in a large group of horses diagnosed with sagittal groove disease (SGD) on low-field MRI. Methods: Retrospective, cross-sectional. Methods: Medical records were searched to identify initial MRI images of horses diagnosed with SGD and these were blindly evaluated using a semi-quantitative grading scheme and novel SGD MRI classification system reflecting p...
Alkhadrawy JMH, Aboelmaaty AM, Abou-Ahmed MM, Ghallab AM.Mares are the only companion animals simulating women in the large diameter of their follicles. Horses start reproduction at the age of three years, and some of them live for >30 years, so aging influences their reproductive capacity. Mares are sensitive to summer heat stress as they can sweat like humans. Unassigned: The current work aimed to study the effects of age (young versus senile), season (cold versus hot), and the hormonal treatments during embryo collection on the dominant and subordinate follicular dynamics and hemodynamics and circulating ovarian hormones in embryo donor mares ...
Giers J, Bartel A, Kirsch K, Müller SF, Horstmann S, Gehlen H.After submaximal exercise, blood values of eventing horses show physiological reactions. This prospective longitudinal study investigated blood parameters in 20 elite eventing horses before and after two-four-star cross-country rides. Using a mixed model adjusting for plasma volume shift, we assessed exercise-dependent parameters and compared blood values with reference ranges for healthy horses at rest. Following exercise, cortisol, triiodothyronine (T3) and thyroxine (T4) showed short-term increases, and superoxide-dismutase showed a small short-term increase. Hepatic values showed short-ter...
Moscovice LR, Sobczak B, Niittynen T, Koski SE, Gimsa U.Although best known for its established role in mediating parturition and lactation, the highly-conserved neuropeptide hormone oxytocin also mediates a range of social and stress-buffering processes across mammalian species. Measurements of peripheral oxytocin in plasma have long been considered the gold standard, but there is increasing interest in developing methods to detect oxytocin non-invasively in saliva. Here we present an analytical and biological validation of a novel method to measure salivary oxytocin (sOXT) in an under-studied research group: farm animals. Given their similarities...
Bujok J, Pavľak A, Walski T, Zigo F, Trochanowska-Pauk N, Bohara R, Miśta D.Combat training of police horses, involving physical activity in the presence of environmental stressors, poses a risk of oxidative stress. This study compared the oxidative imbalance after combat training in horses in the regular police service and in horses that had just been schooled. Blood collection was performed immediately after training and after 16 h rest. The activity of superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), and total antioxidant status (TAS) were determined as the markers of enzymatic antioxidant defence. At the same time, lipid peroxidation (TBAR...
Catalán J, Yánez-Ortiz I, Torres-Garrido M, Ribas-Maynou J, Llavanera M, Barranco I, Yeste M, Miró J.Cryopreservation is a stressful process for sperm, as it is associated with an increased production of reactive oxygen species (ROS). Elevated ROS levels, which create an imbalance with antioxidant capacity, may result in membrane lipid peroxidation (LPO), protein damage and DNA fragmentation. This study aimed to determine whether the membrane LPO and DNA fragmentation of frozen-thawed horse sperm relies upon antioxidant activity, including enzymes (superoxide dismutase (SOD), glutathione peroxidase (GPX), catalase (CAT) and paraoxonase type 1 (PON1)); non-enzymatic antioxidant capacity (Trolo...
Bruschetta G, Zanghì G, Giunta RP, Ferlazzo AM, Satué K, D'Ascola A, Fazio E.Horse transport is considered a cause of stress in animals and is known to affect the 5-HT concentrations in both the brain and other tissues. The aim of this research was to investigate the effect of horse transportation and slaughter stress on plasma serotonin's concentration and the expression levels of the related 5-HT1B and 5-HT2A receptors in PBMCs. Furthermore, the IL-12 levels and a variety of blood parameters, including triglycerides, total cholesterol, glucose, aspartate aminotransferase, creatine phosphokinase, lactate dehydrogenase, were also considered. This research was carried o...
Pereira-Figueiredo I, Rosa I, Sancho Sanchez C.Horses are often still exposed to stressful or inadequate conditions and difficult relationships with humans, despite growing concerns about animal welfare. In the present study, we investigated the impact of different approaches of short-term handling sessions on young Lusitanian horses raised on a high-breed farm, specifically on their later adaptability to humans and stressful environments. Thirty-one foals (3 months old ± 15 days), from both sexes, were separated into three groups, one submitted to 3 consecutive days of handling sessions (Int-H), another to one handling session each month...
Muñoz-Prieto A, Llamas-Amor E, Contreras-Aguilar MD, Ayala I, Martín Cuervo M, Cerón JJ, Hansen S.Ammonia (NH3) and bicarbonate (HCO3) have been related to gastric ulcers in humans. Ammonia is considered a possible cause of gastric ulcers, whereas bicarbonate has a protective function. The presence of ulcers in the stomach of horses is defined as Equine Gastric Ulcer Syndrome (EGUS), which is a frequent disease in this species, and it has been associated with changes in saliva composition, such as in analytes related to inflammation, immune system and oxidative stress. The objectives of this study were (1) to perform an analytical validation of two automated spectrophotometric assays, one ...
Koshyk A, Pohl AJ, Takahashi Y, Scott WM, Sparks HD, Edwards WB.Fractures of the equine metacarpophalangeal (MCP) joint are among the most common and fatal injuries experienced by racehorses. These bone injuries are a direct result of repetitive, high intensity loading of the skeleton during racing and training and there is consensus that they represent a mechanical fatigue phenomenon. Existing work has found the fatigue life of bone to be strongly determined by bone microarchitecture and the resulting stressed volume (i.e., the volume of bone stressed above assumed yield). The purpose of this study was to quantify the influence of bone microarchitecture o...
Capomaccio S, Cappelli K, Barrey E, Felicetti M, Silvestrelli M, Verini-Supplizi A.It is known that moderate physical activity may have beneficial effects on health, whereas strenuous effort induces a state resembling inflammation. The molecular mechanisms underlying the cellular response to exercise remain unclear, although it is clear that the immune system plays a key role. It has been hypothesized that the physio-pathological condition that develops in athletes subjected to heavy training is caused by derangement of cellular immune regulation. The purpose of the present study was to obtain information on endurance horse gene transcription under strenuous conditions and t...
Kang H, Zsoldos RR, Sole-Guitart A, Narayan E, Cawdell-Smith AJ, Gaughan JB.Healthy adult horses can balance accumulation and dissipation of body heat to maintain their body temperature between 37.5 and 38.5 °C, when they are in their thermoneutral zone (5 to 25 °C). However, under some circumstances, such as following strenuous exercise under hot, or hot and humid conditions, the accumulation of body heat exceeds dissipation and horses can suffer from heat stress. Prolonged or severe heat stress can lead to anhidrosis, heat stroke, or brain damage in the horse. To ameliorate the negative effects of high heat load in the body, early detection of heat stress and im...
Perry E, Cross TL, Francis JM, Holscher HD, Clark SD, Swanson KS.The effects of travel stress on the equine cecal microbiota are poorly understood. We hypothesized that travel would affect the equine cecal microbiota. Cecally-cannulated horses (n = 6) were randomly assigned to one of two groups, travel (n = 3) and control (n = 3). Horses received a basal diet (Strategy, Purina Animal Nutrition) with 1.2% body weight mixed grass/alfalfa. Travel horses were transported to an unfamiliar location, stalled to simulate weekend horse show conditions, and then returned to the Southern Illinois University Equine Center. Control horses remained at the equine cente...
Glazar AI, Mullen SF, Liu J, Benson JD, Critser JK, Squires EL, Graham JK.Stallion spermatozoa exhibit osmotic damage during the cryopreservation process. Recent studies have shown that the addition of cholesterol to spermatozoal membranes increases the cryosurvival of bull, ram and stallion spermatozoa, but the exact mechanism by which added cholesterol improves cryosurvival is not understood. The objectives of this study were to determine if adding cholesterol to stallion sperm membranes alters the osmotic tolerance limits and membrane permeability characteristics of the spermatozoa. In experiment one, stallion spermatozoa were treated with cholesterol-loaded cycl...
Priyanka G, Anil Kumar B, Lakshman M, Manvitha V, Kala Kumar B.Ashwagandha ( L. Dunal.) is an important "" of Ayurveda. The roots are extensively used as an adaptogen and for different health issues. Anti-inflammatory, antioxidant, and immune-stimulating effects of Ashwagandha are well-documented. The present study aimed to evaluate the clinical efficacy of Ashwagandha root extract as an adaptogen against various types of stress in horses. A total of 24 Kathiawari horses were selected and randomly divided into four groups. All the horses were provided with normal feed and water . Group 1 (G1) was treated as the control group, and the horses were given a n...
Hada T, Onaka T, Takahashi T, Hiraga A, Yagi K.This study investigated the effects of novelty stress on neuroendocrine activities and running performance in Thoroughbred horses. First, to examine the neuroendocrine responses to novelty stress, we exposed horses to two types of novel environmental stimuli (audiovisual or novel field stimuli). After the stimuli, plasma concentrations of vasopressin, catecholamines and adrenocorticotropin (ACTH), as well as heart rates, were significantly increased in each experiment. Second, we investigated neuroendocrine activities during incremental exercise. Plasma concentrations of vasopressin, catechola...
Christensen JW, Zharkikh TL, Antoine A, Malmkvist J.During riding, horses are frequently exposed to pressure from the rider, e.g. through the bit and reins, but few studies have investigated at which point rein tension becomes uncomfortable for the horse. Objective: To investigate how much rein tension young inexperienced horses are willing to accept in order to obtain a food reward; whether the tension acceptance changes during 3 consecutive test days; and whether rein tension correlates with the expression of conflict behaviour and heart rate. Objective: Pressure-naïve horses will apply only little rein tension in the first voluntary trial, ...
Stull CL.Nine trailer loads of horses (n = 306) transported to slaughter facilities with distances ranging 596 to 2,496 km were studied to characterize the type of horses used in commercial markets and the physiological responses and number of injuries due to transportation under summer environmental conditions. Slaughter horse candidates were middle-aged (11.4+/-.4 yr), possessed moderately fleshy body condition, weighed 432+/-3.3 kg, and were of Quarter Horse or Thoroughbred breeding. The mean weight loss during commercial transport was 4%. The percentage of injured horses was greater (P < .05) fo...
Arnon S, Fisher PW, Pickover A, Lowell A, Turner JB, Hilburn A, Jacob-McVey J, Malajian BE, Farber DG, Hamilton JF, Hamilton A, Markowitz JC, Neria Y.Equine-assisted therapy (EAT) for post-traumatic stress disorder (PTSD) has attracted great interest despite lacking empirical support, a manual, and a standardized protocol. Our team of experts in EAT and PTSD developed an eight-session group EAT treatment protocol for PTSD (EAT-PTSD) and administered it to two pilot groups of military veterans to assess initial effects. We describe the development of the treatment manual, which was used with two pilot groups of veterans. Protocol safety, feasibility, and acceptability were assessed by reported adverse events, treatment completion rates, and ...
Fazio E, Medica P, Cravana C, Ferlazzo A.In order to determine whether therapeutic riding could result in higher levels of stress than recreational riding, hypothalamic-pituitary-adrenal (HPA) axis response was evaluated in six horses by monitoring circulating β-endorphin, ACTH and cortisol concentrations. Horses were already accustomed to be trained both for therapy and riding school activity since 2004. Intervention consisted of 60-minute therapeutic sessions, two times per week for 6weeks with different riders: disabled and recreational riders (session A and B respectively). The therapeutic riders' group (A) consisted of six chil...
Erber R, Wulf M, Becker-Birck M, Kaps S, Aurich JE, Möstl E, Aurich C.Branding is the traditional and well-established method used to mark horses, but recently microchip transponders for implantation have become available. In this study, behaviour, physiological stress variables and skin temperature in foals were determined in response to hot-iron branding (n=7) and microchip implantation (n=7). Salivary cortisol concentrations increased in response to branding (1.8 ± 0.2 ng/mL) and microchip implantation (1.4 ± 0.1ng/mL), but cortisol release over time did not differ. In response to both manipulations there was a transient increase in heart rate (P<0.001) ...
Jacob SI, Geor RJ, Weber PSD, Harris PA, McCue ME.Diagnosis of equine pituitary pars intermedia dysfunction (PPID) remains a challenge as multiple factors (stress, exercise, and time of year) influence ACTH and cortisol concentrations. To assess endocrine status in a study designed to evaluate the effects of age and diet on glucose and insulin dynamics, we performed thyrotropin-releasing hormone (TRH) stimulation tests and overnight dexamethasone suppression tests in March, May, August, and October on 16 healthy Thoroughbred and Standardbred mares and geldings. Horses were grouped by age: adult (mean ± SD; 8.8 ± 2.9 yr; n = 8) and aged (20...
Valenchon M, Lévy F, Prunier A, Moussu C, Calandreau L, Lansade L.The present study investigates how the temperament of the animal affects the influence of acute stress on the acquisition and reacquisition processes of a learning task. After temperament was assessed, horses were subjected to a stressor before or after the acquisition session of an instrumental task. Eight days later, horses were subjected to a reacquisition session without any stressor. Stress before acquisition tended to enhance the number of successes at the beginning of the acquisition session. Eight days later, during the reacquisition session, contrary to non-stressed animals, horses st...
Zhu X, Suarez-Jimenez B, Zilcha-Mano S, Lazarov A, Arnon S, Lowell AL, Bergman M, Ryba M, Hamilton AJ, Hamilton JF, Turner JB, Markowitz JC....While effective treatments for posttraumatic stress disorder (PTSD) exist, many individuals, including military personnel and veterans fail to respond to them. Equine-assisted therapy (EAT), a novel PTSD treatment, may complement existing PTSD interventions. This study employs longitudinal neuro-imaging, including structural magnetic resonance imaging (sMRI), resting state-fMRI (rs-fMRI), and diffusion tensor imaging (DTI), to determine mechanisms and predictors of EAT outcomes for PTSD. Nineteen veterans with PTSD completed eight weekly group sessions of EAT undergoing multimodal MRI assessme...
Albright JD, Mohammed HO, Heleski CR, Wickens CL, Houpt KA.Crib-biting is an equine stereotype that may result in diseases such as colic. Certain breeds and management factors have been associated. Objective: To determine: breed prevalence of crib-biting in US horses; the likelihood that one horse learns to crib-bite from another; and owner perceptions of causal factors. Methods: An initial postal survey queried the number and breed of crib-biting horses and if a horse began after being exposed to a horse with this habit. In a follow-up survey, a volunteer subset of owners was asked the number of affected and nonaffected horses of each breed and the e...
A human-animal relationship can be developed through subsequent interactions, affected by the positive or negative emotional valence of the proceeding one. Horses implement a process of categorization to classify humans with whom they interact as positive, negative, or neutral stimuli by evaluating the kind of approach and the nature of the contact. In these terms, human-animal interactions are emotionally charged events, eliciting specific emotional states in both subjects involved. Although the human-horse relationship has been mainly investigated through behavioral analysis, physiological i...
Mendonça T, Bienboire-Frosini C, Kowalczyk I, Leclercq J, Arroub S, Pageat P.The learning and cognitive challenges that horses may face differ according to the activities in which they are involved. The aim of this investigation was to study the influence of equine activities on the behavioral responses and autonomic nervous system (ANS) activity of adult horses. Forty-one horses were divided into four groups: dressage (9), jumping (10), eventing (13) and equine-assisted activity/therapy (9). A test was created to compare the horses' behavioral and physiological responses to different stimuli. The goal was always to obtain a treat. To study the ANS activity, heart rate...
Fazio E, Medica P, Cravana C, Aveni F, Ferlazzo A.In order to evaluate the effects of short transportation on β-endorphin, adrenocorticotropic hormone (ACTH) and cortisol changes, 12 healthy stallions of Equidae (Equus asinus and Equus caballus) were studied before and after transportation of 50 km. Blood samples were collected 1 week before transportation in basal conditions, immediately before loading and after transportation and unloading, on their arrival at the breeding station. Compared to basal and before values, donkeys showed an increase in circulating ACTH (P < 0.001) and cortisol (P < 0.0005) levels after transportation and ...
Arrazola A, Merkies K.Equine-assisted activities (EAA) for human well-being and health rely on human-horse interactions for therapeutic effect. At-risk participants with mental and emotional difficulties can show poor social skills and functioning relationships, potentially leading to unsuccessful human-horse interaction in EAA. This study addresses the effect of the attachment style (AS) of at-risk adolescents on horse physiology and behaviour during an equine-facilitated learning (EFL) program. Thirty-three adolescents participated in a 10-week EFL program with nine therapy horses (the same therapy horse per adol...
Mazzola SM, Colombani C, Pizzamiglio G, Cannas S, Palestrini C, Costa ED, Gazzonis AL, Bionda A, Crepaldi P.The satisfaction of leisure horses' behavioral needs has begun to be considered a priority, linked to the awareness that horses kept in single boxes may be deprived of social contact and the possibility to perform natural behaviors. Several factors may influence horses' quality of life also in the paddock, and there are very few data on the effects of those variables on leisure horses' chronic stress, measurable in terms of activation of the hypothalamic-pituitary-adrenocortical axis. Therefore, managerial choices faced by owners and stables managers are only based on experience, common sense,...
Henry S, Zanella AJ, Sankey C, Richard-Yris MA, Marko A, Hausberger M.The present study aims to investigate whether the presence of unrelated adult horses at weaning would reduce the social stress of weaning and the emergence of undesirable behaviours. We tested this hypothesis in 32 domestic foals by comparing short and medium term behavioural and physiological responses to weaning in foals maintained in homogeneous groups of peers (PW) to those of foals grouped with both peers and unrelated adults (AW). In total, three trials were conducted, which each trial consisting of one AW group and one PW group. In all foals, weaning was followed by increased vocalizati...
West JB, Mathieu-Costello O.The pulmonary blood-gas barrier has a basic physiological dilemma. On the one hand it needs to be extremely thin for efficient gas exchange. On the other hand it also needs to be immensely strong because the stresses on the pulmonary capillary wall become extremely high when the capillary pressure rises on exercise. Maximal hydrostatic pressures in human pulmonary capillaries during exercise are not accurately known but must exceed 30 mmHg. In some animals, for example thoroughbred horses, the capillary pressure rises to about 100 mmHg. These pressures cause stresses in the capillary wall of 5...
Faubladier C, Chaucheyras-Durand F, da Veiga L, Julliand V.This study evaluated the effect of transportation on fecal bacterial communities and activities in horses with or without supplementation of live yeast and attempted to link those effects with changes in blood stress markers. Four mature horses were assigned to a crossover design and fed a basal diet (60:40 forage to concentrate; 1.45% BW on a DM basis), with or without supplementation, of 2 × 10(10) cfu/d of Saccharomyces cerevisiae CNCM I-1077. After a 14-d adaptation to dietary treatments, the 5-d experiment started 1 d before transportation (d -1). At d 0, horses were simultaneously trans...
Esch L, Wöhr C, Erhard M, Krüger K.Domesticated horses are constantly confronted with novel tasks. A recent study on anecdotal data indicates that some are innovative in dealing with such tasks. However, innovative behavior in horses has not previously been investigated under experimental conditions. In this study, we investigated whether 16 horses found an innovative solution when confronted with a novel feeder. Moreover, we investigated whether innovative behavior in horses may be affected by individual aspects such as: age, sex, size, motor and sensory laterality, fecal stress hormone concentrations (GCMs), and task-related ...
García BM, Moran AM, Fernández LG, Ferrusola CO, Rodriguez AM, Bolaños JM, da Silva CM, Martínez HR, Tapia JA, Peña FJ.Cryopreservation introduces extreme temperature and osmolality changes that impart lethal and sublethal effects on spermatozoa. Additionally, there is evidence that the osmotic stress induced by cryopreservation causes oxidative stress to spermatozoa. The main sources of reactive oxygen species in mammalian sperm are the mitochondria. In view of this, the aim of our study was to test whether or not osmotic stress was able to induce mitochondrial damage and to explore the osmotic tolerance of the mitochondria of stallion spermatozoa. Ejaculates from 7 stallions were subjected to osmolalities ra...
Berghold P, Möstl E, Aurich C.Stressful events may contribute to low reproductive efficiency due to glucocorticoid-mediated inhibition of hormone secretion in a variety of species. We therefore investigated effects of stress related to management of mares around artificial insemination on secretion of cortisol and fertility parameters. To avoid further disturbance of mares by frequent blood sampling, faecal cortisol metabolites (fCM) were determined instead (sample collection at 8-h intervals). A total of 50 mares (16 maiden, 17 barren, 12 foaling, 5 teaching mares) were included in the study. Mares were brought to the AI ...
Keenan DM, Alexander S, Irvine C, Veldhuis JD.Cortisol is an important mediator of physiological stress responses. Hypothalamic CRH and arginine vasopressin (AVP) and pituitary ACTH, in addition to hypothalamic and pituitary cortisol feedback, regulate cortisol secretion. Importantly, joint interactions among the four, rather than the signal of any one hormone, govern this life-preserving axis. Quantifying in vivo strength of such joint interactions has been difficult, especially without direct injection of cortisol, CRH, AVP, or ACTH. The goal of the present research was to estimate these joint feedback and feedforward interactions in vi...
König von Borstel U, Euent S, Graf P, König S, Gauly M.The aim of the present study was to compare horses' heart rate (HR), heart rate variability (RMSSD, pNN50) and behaviour in the same temperament test when being ridden, led, and released free. Behavioural measurements included scores and linear measurements for reactivity (R), activity (A), time to calm down (T) and emotionality (E), recorded during the approach (1) and/or during confrontation with the stimulus (2). Sixty-five horses were each confronted 3 times (1 ridden, 1 led, 1 free running in balanced order) with 3 novel and/or sudden stimuli. Mixed model analysis indicated that leading r...
Christensen JW, Malmkvist J, Nielsen BL, Keeling LJ.In fear-eliciting situations, horses tend to show flight reactions that can be dangerous for both horse and man. Finding appropriate methods for reducing fearfulness in horses has important practical implications. Objective: To investigate whether the presence of a calm companion horse influences fear reactions in naive subject horses. Objective: The presence of a habituated (calm) companion horse in a fear-eliciting situation can reduce fear reactions in naive subject horses, compared to subject horses with a nonhabituated companion (control). Methods: Minimally handled (n = 36), 2-year-old s...
