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.
Bukhari SSUH, McElligott AG, Parkes RSV.There are approximately 112 million working equids in developing countries, many of which are associated with brick kilns. Brick kilns and overloading are associated with welfare problems in working equids. Understanding equids' abilities and influencing factors are important for both effective performance and welfare. Traditionally, measurement of the amount of 'bone' was used, and more recently, gait symmetry has been identified as a potential marker for loading capacity. Assessment of stride parameters and gait kinematics provides insights into adaptations to loading and may help determine ...
Gehlen H, Krumbach K, Thöne-Reineke C.This literature review was aimed at analyzing whether stallion husbandry in groups is possible and desirable or poses risks. This was determined on the basis of different studies in order to be able to give practical recommendations from the viewpoint of animal welfare. Consequently, 50 different sources were analyzed, as well as observations of an experiment of the Swiss National Stud on the subject of change from single-stallion to group husbandry and its influence on animal welfare. The results revealed that stallion husbandry in groups is possible but still rarely practiced. It was found t...
Ricci-Bonot C, Romero T, Nicol C, Mills D.Social buffering occurs when the presence of one animal attenuates another's stress response during a stressful event and/or helps the subject to recover more quickly after a stressful event. Inconsistent previous results might reflect previously unrecognised contextual influences, such as the nature of the stimulus presented or social factors. We addressed these issues in a two-part study of horses paired with familiar (16 subjects) or unfamiliar (16 subjects) companions. Each subject performed 4 tests in a counterbalanced order: novel object test (static ball)-alone or with companion; and um...
Zoccante L, Marconi M, Ciceri ML, Gagliardoni S, Gozzi LA, Sabaini S, Di Gennaro G, Colizzi M.Equine-assisted activities and therapies (EAAT) have been suggested to improve adaptive behavior, and possibly motor function, in autism spectrum disorder (ASD). This study investigated the effects of EAAT on adaptive behavior and motor function in 15 children with ASD (13 males) aged 7-15 years as well as the impact of EAAT on the magnitude of stress in the parent-child system and the evolution in the child interaction with both the trained therapist and the therapeutic animal through the 20 weekly sessions of EAAT. EAAT were associated with greater adaptive behavior and coordination (all ...
Johnson RA, Albright DL, Marzolf JR, Bibbo JL, Yaglom HD, Crowder SM, Carlisle GM, Grindler K, Harms N, Willard A, Wassman M, Russell CL.Posttraumatic stress disorder commonly occurs among U.S. military veterans. Therapeutic horseback riding (THR) has emerged as an adjunct therapy. We explored 20 veterans' perceived benefits, drawbacks and views of a 6-week THR program. Participants had confirmed diagnoses of posttraumatic stress disorder, traumatic brain injury, or both. Veterans rode the same horse weekly, the same day, at the same time. Data were collected as part of a randomized clinical trial testing the effects of THR on Post-Traumatic Stress Disorder. Veterans responded to an open-ended questionnaire. Content analysis wa...
Latham CM, Dickson EC, Owen RN, Larson CK, White-Springer SH.To test the hypothesis that complexed trace mineral supplementation would increase antioxidant capacity and decrease muscle oxidative stress and damage in young horses entering an exercise training program, Quarter Horses (mean [Formula: see text] SD; 9.7 ± 0.7 mo) balanced by age, sex, and BW were assigned to receive complexed (CTM; n = 8) or inorganic (INORG; n = 8) trace minerals at -12 week relative to this study. Blood and muscle samples were collected before (week 0) and after 12 week of light exercise training surrounding a 1.5-h trailer stressor. Muscle glutathione peroxid...
Janczarek I, Stachurska A, Wilk I, Wiśniewska A, Różańska-Boczula M, Kaczmarek B, Łuszczyński J, Kędzierski W.The horse's welfare and, consequently, the emotional arousal may be connected with stressful environmental conditions. This study aimed to determine whether horses show behavioural or physiological symptoms of thermal discomfort and if their behaviour and cardiac parameters are related to freely chosen insolated (IS), shaded (SH), or water sprayed (with a mist curtain (MC)) areas in a paddock under heat conditions (29-32 °C, 42.0 ± 1.5% humidity). Twelve adult horses freely moving in the paddock were studied during a 45 min solitary turnout. Six cardiac variables, locomotor, and non-locomoto...
Auer U, Kelemen Z, Engl V, Jenner F.Horses' behavior can provide valuable insight into their subjective state and is thus a good indicator of welfare. However, its complexity requires objective, quantifiable, and unambiguous evidence-based assessment criteria. As healthy, stress-free horses exhibit a highly repetitive daily routine, temporal quantification of their behavioral activities (time budget analysis) can assist in equine welfare assessment. Therefore, the present systematic review aimed to provide an up-to-date analysis of equine time budget studies. A review of the literature yielded 12 papers that fulfilled the inclus...
Joongpan W, Tongsangiam P, Poochipakorn C, Charoenchanikran P, Chanda M.Horses were provided full-time housing in unfamiliar vector-protected facilities during the African horse sickness (AHS) outbreak in Thailand. This study aimed to investigate the impact of this housing arrangement on the equine stress response. Nine healthy horses were housed in both a traditional barn and a vector-protected barn. Equine behavior and stress response data were collected in association with the housing environment and time of day. The mean behavioral score of horses housed in the vector-protected barn was lower at night than during the day. In addition, the horses' mean heart ra...
Arfuso F, Giannetto C, Giudice E, Fazio F, Panzera M, Piccione G.The current study aimed to investigate whether peripheral modulators of serotoninergic function and neurohumoral factors' changes in athletic horses during an official jumping competition, and to evaluate their relationship with the physical performance of competing horses. From 7 Italian Saddle mares (6-9 years; mean body weight 440 ± 15 kg), performing the same standardized warm-up and jumping course during an official class, heart rate (HR) was monitored throughout the competition. Rectal temperature (RT) measurement, blood lactate and glucose concentration, serum tryptophan, leucine, vali...
Mach N, Lansade L, Bars-Cortina D, Dhorne-Pollet S, Foury A, Moisan MP, Ruet A.Elite horse athletes that live in individual boxes and train and compete for hours experience long-term physical and mental stress that compromises animal welfare and alters the gut microbiota. We therefore assessed if a temporary period out to pasture with conspecifics could improve animal welfare and in turn, favorably affect intestinal microbiota composition. A total of 27 athletes were monitored before and after a period of 1.5 months out to pasture, and their fecal microbiota and behavior profiles were compared to those of 18 horses kept in individual boxes. The overall diversity and mic...
Keating DL, Lehman JS, Burk SV.Identification of factors associated with parasite infestation in horses could reduce frequency of anthelmintic administration and slow development of anthelmintic resistance. The study aim was to evaluate management factors, equine characteristics, and equine salivary cortisol concentrations for association with strongyle-type egg shedding levels. As immunocompromised horses appear to be more susceptible to parasite infestation, it was hypothesized that salivary cortisol concentration could be associated with parasite egg shedding. Saliva and fecal samples were collected from 200 horses acros...
King L, Cullen SJ, O'Connor S, McGoldrick A, Pugh J, Warrington G, Losty C.Racehorse trainers play an important role within the horseracing industry. Despite this, scarce empirical information exists regarding the mental health of this population. Thus, the purpose of the present study was to explore the prevalence of symptoms related to common mental disorders (CMDs) and their associations with specific risk factors for CMD. Participants completed an anonymous online questionnaire. CMDs were assessed including distress, depression, generalized anxiety and adverse alcohol use. The risk factors examined included career dissatisfaction, social support and financial dif...
Fujiyama M, Jones T, Duke-Novakovski T.To evaluate perioperative stress-related hormones in isoflurane-anesthetized horses administered infusions of dexmedetomidine alone or with butorphanol or remifentanil, compared with ketamine-morphine. Methods: Randomized, prospective, nonblinded clinical study. Methods: A total of 51 horses undergoing elective surgical procedures. Methods: Horses were premedicated with xylazine, anesthesia induced with ketamine-diazepam and maintained with isoflurane and one of four intravenous infusions. Partial intravenous anesthesia (PIVA) was achieved with dexmedetomidine (1.0 μg kg hour; group D; 12 hor...
Colborne GR, Tang L, Adams BR, Gordon BI, McCabe BE, Riley CB.During transport, horses are subjected to acceleration in three dimensions, rapid braking, turning, noise, and other stressors. The animal's ability to make postural corrections may be insufficient to prevent injury or distress, and so knowledge of the compensatory motion patterns of the horse in the trailer is a necessary precondition for smart design of transport systems. A custom two-horse trailer was built for this project. It had a horse compartment 1.85 m wide by 3.95 m long, with adjustable bulkheads and a centre divider separating the horses. The floor was instrumented with 24 shearbea...
Uldahl M, Christensen JW, Clayton HM.Riders need core stability to follow and guide the horse's movements and avoid giving unintended or conflicting signals. This study evaluated the rider's performance of exercises on a gymnastic ball with on-horse performance and indicators of stress in the horse. Twenty experienced riders were scored performing three exercises on a gymnastic ball and for quality and harmony when riding based on evaluation of video recordings in which conflict behaviours were evident. The horse's heart rate and number of conflict behaviors during the riding test and cortisol levels after completion of the test ...
Hartmann E, Rehn T, Christensen JW, Nielsen PP, McGreevy P.The study investigated equine responses to novelty and handling, aiming to reveal whether horse-human relationships reflect criteria of an attachment bond. Twelve adult Standardbreds were subjected to a fear-eliciting test (novel objects presented close to two humans) and a handling test (being led passing novel objects) to study attachment-related behaviours and ease of handling. The tests were performed both before (pre-test) and after (post-test) horses had been trained by the same female handler (10 sessions of 15 min). Horses were assigned to three groups of four, each of which underwent ...
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...
Willmund G, Zimmermann P, Alliger-Horn C, Varn A, Fischer C, Parent I, Sobottka A, Bering R, Rose C, Ströhle A, Köhler K.Many traumatised individuals suffering from deployment related PTSD report severe problems in their relationships. Up until now, the therapeutic interventions used by the German Armed Forces have rarely targeted these problems through the integration of partners. For this reason, a Program designed specifically for couples was developed. In this prospective study equine-assisted psychotherapy was applied to soldiers and their spouses. The study population consisted of n = 36 couples, divided in n = 20 therapy group with a inpatient equine-assisted intervention and a 16-couples control grou...
Joonè CJ, Gradil CM, Picard JA, Taylor JD, de Tonnerre D, Cavalieri J.The primary aim of this study was to investigate the contraceptive efficacy of a self-assembling uterine device (iUPOD™) in the mare. In addition, the effects of iUPODs on oestrous cyclicity, uterine health and circulating concentrations of cortisol were evaluated. Methods: Domestic mares underwent oestrous monitoring and artificial insemination. After subsequent ovulation, mares underwent either placement (n = 7) or sham placement (n = 7; controls) of an iUPOD device. Devices were left in place for at least 3 months. Pregnancy diagnoses were carried out 14 days post-ovulation, with any pr...
Dockalova H, Zeman L, Horky P.Veterinarians can recommend milk thistle for the treatment of equine liver disease and laminitis. Milk thistle seed cakes were fed in the range of normal feed doses in this study. The milk thistle seed cakes were fed (twice a day) to the experimental group of the horses ( = 5) and biochemical blood markers (TP, Albumin, ALT (alanine transaminase), AST (aspartate transaminase), ALP (alkaline phosphatase), GGT (gamma-glutamyltransferase), Bilirubin, Cholesterol, HDL (high-density lipoprotein), LDL (low-density lipoprotein), TAG (triacylglycerol), BHB (beta-hydroxybutyric acid), NEFA (non-esterif...
Witkowska-Piłaszewicz O, Grzędzicka J, Seń J, Czopowicz M, Żmigrodzka M, Winnicka A, Cywińska A, Carter C.Assuring a high level of animal welfare is a critical aspect of contemporary animal husbandry. Equine athletes begin their careers at a very young age when they are still developing and they are both physically and mentally immature. Lack of scientific knowledge of the stress related to horse racing impedes the development of optimal training programs to attain equilibrium between the best sport results and optimal welfare. This study aimed to determine the influence of the intensity and type of physical activity on peripheral blood cortisol concentration. Thirty untrained Arabians, 9 enduranc...
Jones McVey R.This article describes the virtue of bravery in British equestrian culture and suggests that riders' tactics for bolstering bravery may have negative implications on equine welfare. These observations are based on 14 months of ethnographic research among amateur riders and the professionals who support them (n = 35), utilising participant observation and Dictaphone recordings. Riders suffering from 'confidence issues' could be belittled and excluded. Instructors' approaches towards bolstering bravery involved encouraging riders to 'get tough'-on both themselves and on their horses. Narrative t...
Christensen JW, Ahrendt LP, Malmkvist J, Nicol C.The mechanisms underlying individual variation in learning are key to understanding the development of cognitive abilities. In humans and primates, curiosity has been suggested as an important intrinsic factor that enhances learning, whereas in domesticated species research has primarily identified factors with a negative effect on cognitive abilities, such as stress and fearfulness. This study presents the first evidence of a link between object-directed curiosity and learning performance in young horses in two very different learning tasks (visual discrimination and pressure-release). We exp...
Rossetto L, Farcey MF, Bilbao MG, Bartolomé JA, Gallelli MF, Miragaya MH.The stress associated with training may reduce reproductive efficiency in Criollo stallions. The objective of this study was to compare semen quality and hormone concentrations in Criollo stallions under training or under regular field conditions. Criollo breed stallions (n = 18) were evaluated during the spring. The exercise group (n = 9) performed 1 hour of exercise per day and participated in competitions during the experimental period. The control group (n = 9) neither performed exercise nor participated in competitions. Serum and semen samples were obtained every 15 days (two separat...
Suagee-Bedore JK, Linden DR, Bennett-Wimbush K.Group turnout provides important socializing opportunities for horses, particularly those that are primarily stalled. A high percentage of equine injuries occur during group turnout, which could partly be due to the physical constraints of fencing. To investigate appropriate paddock sizes for group turnouts, horses (n = 12) from a single herd were divided into groups of 4, stalled for 24 hours, and then turned out for 1 hour into one of three differently sized pens: 342, 263, and 184 m per horse. Groups rotated through pens across 3 days, receiving one treatment per day. Blood was sampled ...
Janczarek I, Stachurska A, Kędzierski W, Pawlak EW, Wilk I, Zyglewska K, Paszkowska A, Ryżak M, Wiśniewska A.The current predation threat of domestic horses is generally low, and horses do not know predators' frightening cues. We studied whether horses still recognise predation threats. The aim of the study was to analyse the emotional response of purebred Arabian horses (Arabian) and Polish Konik horses (Konik) to an Arabian panther (Panthera pardus nimr) (panther) growl and a grey wolf (Canis lupus) (wolf) howl. Panther vocalisation was known to Arabian ancestors, whereas ancestors of Konik knew wolf vocalisation. The response to the howls of golden jackals (Canis aureus) (jackal), which did not pr...
Mott RO, Hawthorne SJ, McBride SD.Measuring animal stress is fundamentally important for assessing animal emotional state and welfare. Conventional methods of quantifying stress (cortisol levels, heart rate/heart rate variability) require specialist equipment and are not instantly available. Spontaneous blink rate (SBR) has previously been used to measure stress responses in humans and may provide a non-invasive method for measuring stress in other animal species. Here we investigated the use of SBR as a measure of stress in the domestic horse. SBR was measured before and during a low-stress event (sham clipping) and compared ...
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...
Samol MA, Uzal FA, Hill AE, Arthur RM, Stover SM.Tibial fractures cause ~3% of racehorse deaths. Pre-existing stress fractures have been associated with multiple racing and training fractures, but not complete tibial fractures. Objective: To describe racehorse tibial fractures and compare signalment and exercise histories of affected and control racehorses. Methods: Retrospective analysis of necropsy reports. Methods: Racehorses that had a complete tibial fracture (1990-2018) were retrospectively reviewed. Signalment and exercise histories of affected horses were compared to 1) racehorses that died because of non-tibial musculoskeletal injur...
Górecka-Bruzda A, Fureix C, Ouvrard A, Bourjade M, Hausberger M.Yawning is rare in herbivores which therefore may be an interesting group to disentangle the potential function(s) of yawning behaviour. Horses provide the opportunity to compare not only animals living in different conditions but also wild versus domestic species. Here, we tested three hypotheses by observing both domestic and Przewalski horses living in semi-natural conditions: (i) that domestic horses may show an elevated rate of yawning as a result of the domestication process (or as a result of life conditions), (ii) that individuals experiencing a higher level of social stress would yawn...
Les CM, Stover SM, Keyak JH, Taylor KT, Kaneps AJ.Our hypothesis was that post-yield mechanical behavior of compact bone material in compression, defined as the stress, strain, or energy absorbed between 0.2% strain-offset and the point of maximum stress, is correlated with material density, modulus, strength, histomorphometric evidence of remodeling, and post-failure gross specimen morphology. Post-yield behavior of compact bone material from the third metacarpal bone of 10 horses, ages 5 months to 20 years, was investigated using single-load compression-to-failure. The post-yield stress, strain, and absorbed energy were compared with the co...
Raekallio M, Leino A, Vainio O, Scheinin M.Thirty-nine horses were given detomidine 10 micrograms/kg bodyweight (bwt) intravenously (iv) and six horses were given a corresponding volume of saline solution before minor procedures. Venous blood samples were collected for catecholamine and cortisol determination immediately before the detomidine or saline injection and 20 mins after it. The behaviour of the horse at the time of detomidine injection and the extent of sedation were evaluated. Plasma adrenaline, noradrenaline and the catecholamine metabolites, 3,4-dihydroxyphenylglycol (DHPG) and 3,4-dihydroxyphenylacetic acid (DOPAC), and c...
Medill SA, Janz DM, McLoughlin PD.Steroid-hormone concentrations from non-invasively obtained biomarkers, like hair, can provide a representation of circulating hormones diffused over relatively long time periods (e.g., weeks or months). The hormone cortisol is often associated with physiological or even psychological stress, while testosterone is strongly associated with male development and reproductive success. Increasingly, studies are using hormone levels derived from hair to make inferences among both domestic animals and wildlife. For horses, all previous hair hormone analysis has been done on companion or working anima...
Crevier N, Pourcelot P, Denoix JM, Geiger D, Bortolussi C, Ribot X, Sanaa M.To determine the local variations of mechanical properties of the equine superficial digital flexor tendon (SDFT). Methods: 10 SDFT of adult horses, selected for absence of abnormality. Methods: Needles (with a dark marker at both ends) pinned perpendicularly through each tendon to delimit 7 segments. Each tendon was tested in traction until rupture; test was filmed, using an 8-mm video camera. For each image, the coordinates of the center of mass of each marker and the corresponding force were registered. The third-degree polynomial that best fits the stress-strain curve thus obtained was cal...
Jenkinson DM, Elder HY, Bovell DL.The condition of anhidrosis is described in this review, and the latest theories on the causal factors are explored. The evidence supports the hypothesis that anhidrosis is an inappropriate response to prolonged climatic stress (generally combined heat and high humidity), which can be evoked in a small (approximately 10 +/- 5%) proportion of the equine population. It is caused by gradual failure of the glandular secretory cell processes, initiated by desensitization and subsequent down-regulation of the cell receptors as a result of continued adrenaline-driven hyperactivity. It progresses thro...
Holtby AR, McGivney BA, Browne JA, Katz LM, Murphy KJ, Hill EW.Thoroughbred horses are bred for competitive racing and undergo intense training regimes. The maintenance of physical soundness and desirable behavioural characteristics are critical to the longevity of a racing career. Horses intended for Flat racing generally enter training as yearlings and undergo introductory training prior to exercise conditioning for racing. This period requires rapid adjustment to a novel environment. As a prey animal, a horse's 'fight-or-flight' response is highly adapted, in which a well-understood component of this response, the hypothalamic-pituitary-axis, is activa...
Cerasoli F, Podaliri Vulpiani M, Saluti G, Conte A, Ricci M, Savini G, D'Alterio N.Horses have always been animals used for companionship, work, transportation, and performance purposes over the history of humanity; there are different ways of managing horses, but studies on how horse welfare is influenced by different activities and managements are scanty. Understanding how the management, the environment, and the different uses of horses can affect the level of stress and well-being is important not only for people associated with horses. Three groups of horses with different management, environments, and activities were selected: (1) stabled horses ridden frequently, (2) ...
Rossdale PD, Burguez PN, Cash RS.Blood neutrophil/lymphocyte ratio and plasma cortisol levels were measured before and after (1) the injection of adrenocorticotrophic hormone (ACTH1-24) in 8 Thoroughbreds and (2) exercise in 5 Thoroughbreds in training. Plasma cortisol levels were significantly (P less than 0.01) increased within 60 mins of injection of ACTH1-24 and immediately after exercise. The mean neutrophil/lymphocyte ratio altered significantly (P less than 0.01) at 240 mins after ACTH1-24 administration and at 180 mins after a training gallop. A transient lymphocytosis occurred following exercise.
Jansen F, Van der Krogt J, Van Loon K, Avezzù V, Guarino M, Quanten S, Berckmans D.The objective of this research was to develop a non-invasive method to detect an emotional response of a horse to novelty during physical activity. Two horses performed 20 trials each, in which the horse's heart rate (HR) and physical activity were continuously measured. The relationship between the horse's physical activity and HR was described by a mathematical model allowing online decomposition of the horse's HR into a physical component and a component containing information about its emotional state. Exposure to the novel object resulted in an increase in the emotional component of HR, w...
Despite the number of postpartum handling that a newborn experiences, few studies focus on their long-term consequences. In rats, regular long separations from the mother, during the early life, led to modifications of the locomotor activity when the animal is confronted to a stressor. In horses, one component of the behavioral response to stressful situation is active locomotion. We wondered if the routine postpartum handling undergone by foals, would affect their level of reactivity or the way they express their stress, when older. One single prolonged bout of handling just after birth clear...
McCarthy RN, Jeffcott LB, Funder JW, Fullerton M, Clarke IJ.A controlled period of submaximal exercise on a treadmill was used as a standardised stress test in 6 young horses to monitor the effects of training. Circulating plasma concentrations of immunoreactive beta-endorphin (IR beta-EP) were measured before, during and after the exercise period. The stress test was conducted on 3 occasions during an intensive training program lasting 14 weeks. In week 3 a marked increase in plasma IR beta-EP (P = 0.003) was demonstrated as a result of training, but by the last exercise test performed in week 9 no significant increase in plasma IR beta-EP concentrati...
Janczarek I, Stachurska A, Wilk I, Wiśniewska A, Różańska-Boczula M, Kaczmarek B, Łuszczyński J, Kędzierski W.The horse's welfare and, consequently, the emotional arousal may be connected with stressful environmental conditions. This study aimed to determine whether horses show behavioural or physiological symptoms of thermal discomfort and if their behaviour and cardiac parameters are related to freely chosen insolated (IS), shaded (SH), or water sprayed (with a mist curtain (MC)) areas in a paddock under heat conditions (29-32 °C, 42.0 ± 1.5% humidity). Twelve adult horses freely moving in the paddock were studied during a 45 min solitary turnout. Six cardiac variables, locomotor, and non-locomoto...
Jones MM, Nuñez CMV.Stress responses can be triggered by several physical and social factors, prompting physiological reactions including increases in glucocorticoid concentrations. In a population of feral horses (Equus caballus) on Shackleford Banks, North Carolina, females previously immunized with the immunocontraceptive agent porcine zona pellucida (PZP) change social groups (bands) more often than unimmunized females, disrupting the social stability within the population. We assessed the effects of increased female group changing behavior (or female turnover) on individual male stress by comparing fecal cor...
Cheal EJ, Snyder BD, Nunamaker DM, Hayes WC.The objective of this investigation was to examine the stress-morphology relationships for trabecular bone around implants with different surface characteristics. Stainless steel spheres with either a polished surface or a sintered-bead porous coating were implanted unilaterally into equine patellae and maintained for a 6 month period. Stereological methods were used to quantify the trabecular bone morphology and finite element analyses were performed to predict the trabecular bone stresses. In general, the remodeling response around the smooth implants was greater than that around those porou...
Ayala MD, Carrillo A, Iniesta P, Ferrer P.Different welfare indicators were studied in three patients with psychomotor alterations and in two horses throughout 9-10 equine assisted therapy sessions in each patient. In horses, heart and respiratory rates, blood pressure, temperature and behavioral signs were studied. In patients, heart rate, oxygen saturation, temperature, sleep quality, psychomotor and emotional parameters were analyzed. Data collection was recorded in the anticipatory phase (15 min before the start of the session), two interaction phases (after 30 min of horse-patient interaction on the ground and on horseback, respe...
Easton-Jones C.Equid gammaherpesviruses are ubiquitous and widespread in the equine population. Despite their frequent detection, their contribution to immune system modulation and the pathogenesis of several diseases remains unclear. Genetic variability and the combination of equid gammaherpesvirus strains a horse is infected with might be clinically significant. Initial gammaherpesvirus infection occurs in foals peripartum with latency then established in peripheral blood mononuclear cells. A novel EHV-5 study suggests that following inhalation equid gammaherpesviruses might obtain direct access to T and B...
Coelho CS, Silva ASBA, Santos CMR, Santos AMR, Vintem CMBL, Leite AG, Fonseca JMC, Prazeres JMCS, Souza VRC, Siqueira RF, Manso Filho HC, Simões JSA.The purpose of this study was to investigate stressful responses during a 6-week training protocol in young Lusitano horses used for dressage. The hypothesis was that the proposed training protocol would improve fitness and ensure the welfare of the animals by reducing stress predictors. Nine 4-year-old horses were evaluated before (M1) and six weeks after (M2) beginning a training protocol. The training program was performed six times per week and included 40−80 min of individually intensity-adjusted preparatory exercises for dressage. For both moments, the horses were examined before (T0) ...
The measure of hair cortisol concentration (HCC) is becoming an emerging approach to monitor mid-/long-term stress in animals, so it is more and more important to develop accurate and reliable methods. In the light of this, the aim of the present study was to compare mane HCCs of 47 horses with different managements, by means of an immunoassay (ELISA) and liquid chromatography coupled to hybrid high-resolution mass spectrometry (LC-HRMS/MS). After the washing step, the ground hair was extracted with methanol. The extract was evaporated and redissolved in two different aqueous solutions, depend...
Thornton J.To determine if the microclimate is detrimental to horses during international air transportation in an enclosed container. Methods: On each of two 12 h and two 24 h flights three horses were transported in an enclosed container designed to prevent exposure to insect vectors. Heart rates were monitored throughout and blood samples were collected periodically. Air in the container was sampled for bacteria and fungal spores and the temperature and relative humidity were recorded inside and outside the container periodically during the flight. On the two 12 h flights similar observations were mad...
Christensen JW.The ability of horses to habituate to novel objects influences safety in the horse-human relationship. However, the effectiveness of different habituation techniques has not been investigated in detail. Objective: 1) To investigate whether horses show increased stress responses when negatively reinforced to approach novel objects, compared with horses allowed to voluntarily explore the objects and 2) whether a negatively reinforced approach facilitates object habituation. Methods: Twenty-two 2-3-year-old Danish Warmblood geldings were included. Half of the horses (NR group) were negatively rei...
Baker B, Gaffin SL, Wells M, Wessels BC, Brock-Utne JG.Endotoxins (lipopolysaccharides-LPS) and anti-endotoxin IgG antibodies were measured in racehorses before and after races of 1,000, 2,000 and 2,800 m. Results show that the mean plasma concentration of endotoxin increased significantly (p less than 0.02) while the anti-LPS IgG concentration decreased significantly (p less than 0.005) in all horses following the races. Pre-race and post-race anti-LPS IgG levels in racing-fit racehorses were significantly higher than in untrained horses (p less than 0.05). The possibility therefore exists that training-induced stress leads to leakage of LPS into...
Friend TH, Martin MT, Householder DD, Bushong DM.To characterize progressive patterns of dehydration, stress responses, and water consumption in horses transported long distances in hot weather and to evaluate various measurements in detecting dehydration and stress in transported horses. Methods: Prospective study. Methods: 30 mature, healthy horses. Methods: The following 4 treatment groups were studied: horses that were penned and offered water every 5 hours (n = 5), horses that were penned and not offered water (5), horses that were transported in a truck and offered water every 5 hours (10), and horses that were transported and not offe...
Emanuel D, Kästner SBR, Delarocque J, Grob AJ, Bienert-Zeit A.The aim of this prospective clinical trial was to compare the influence of butorphanol, buprenorphine and levomethadone on sedation quality and postoperative analgesia in horses undergoing cheek tooth extraction. Fifty horses were assigned to three groups prior to oral cheek tooth extraction. Horses were treated with acepromazine, followed by a detomidine bolus, one of the three opioids and both a nerve block and gingival anaesthesia. During the surgery, sedation was maintained with a detomidine constant rate infusion. After surgery, the quality of sedation, surgical conditions and severity of...
Krueger K, Schwarz S, Marr I, Farmer K.For centuries, a goal of training in many equestrian disciplines has been to straighten the horse, which is considered a key element in achieving its responsiveness and suppleness. However, laterality is a naturally occurring phenomenon in horses and encompasses body asymmetry, motor laterality and sensory laterality. Furthermore, forcibly counterbalancing motor laterality has been considered a cause of psychological imbalance in humans. Perhaps asymmetry and laterality should rather be accepted, with a focus on training psychological and physical balance, coordination and equal strength on bo...
Casella S, Vazzana I, Giudice E, Fazio F, Piccione G.The changes of cortisol, red blood cells (RBC), hemoglobin (Hb), hematocrit (Hct), heart rate (HR), respiratory rate (RR) and rectal temperature (RT) were evaluated after a reining training session in eight Quarter Horses. All parameters were measured before exercise (T0), immediately after exercise (T1), 1 h after exercise (T2), 2 h after exercise (T3) and 24 h after exercise (T4). One-way analysis of variance (ANOVA) for repeated measures, followed Bonferroni's post hoc test, showed a significant effect of the reining training session (P < 0.0001) on cortisol, RBC, Hb, Hct, HR, RR and RT. Si...
Carroll GL, Matthews NS, Hartsfield SM, Slater MR, Champney TH, Erickson SW.Six ponies were used to investigate the effect of tolazoline antagonism of detomidine on physiological responses, behavior, epinephrine, norepinephrine, cortisol, glucose, and free fatty acids in awake ponies. Each pony had a catheter inserted into a jugular vein 1 hour before beginning the study. Awake ponies were administered detomidine (0.04 mg/kg intravenously [i.v.]) followed 20 minutes later by either tolazoline (4.0 mg/kg i.v.) or saline. Blood samples were drawn from the catheter 5 minutes before detomidine administration (baseline), 5 minutes after detomidine administration, 20 minute...
Hinterhofer C, Stanek C, Haider H.A finite element (FE) hoof capsule was built as a small, symmetrical forelimb hoof on IDEAS* as a model for calculation and visualisation of stress and displacement of the equine hoof capsule. The model's loading was performed according to the suspension of the coffin bone within the hoof wall (pulling force) and over the sole and frog (compressing force) with a total of 3000 N. Restraints of the model's ground nodes and surface wall nodes were defined for simulation of 4 shoeing situations: a regular horseshoe, a horseshoe with a toe clip, a horseshoe with regular side clips and a horseshoe w...
Smith MR, Wright IM.Fractures of the proximal phalanx are generally considered to result from monotonic supraphysiological loads, but radiological observations from clinical cases suggest there may be a stress-related aetiology. Objective: To determine whether there are radiologically identifiable prodromal changes in Thoroughbred racehorses with confirmed parasagittal fractures of the proximal phalanx. Methods: Retrospective cross-sectional study. Methods: Case records and radiographs of Thoroughbred racehorses with parasagittal fractures of the proximal phalanx were analysed. Thickness of the subchondral bone p...
