Topic:Animal Models
Animal models in equine research refer to the use of horses or other species to study biological and disease processes relevant to equine health. These models facilitate the investigation of various physiological and pathological conditions, allowing researchers to explore disease mechanisms, test therapeutic interventions, and understand genetic influences on health outcomes. Horses themselves are often studied as models for human diseases due to certain physiological similarities. Additionally, other species may be used to model equine-specific conditions when direct study in horses is impractical. This page compiles peer-reviewed research studies and scholarly articles that explore the application, development, and findings of animal models in equine research.
True blue: S-opsin is widely expressed in different animal species. Colour vision in animals is an interesting, fascinating subject. In this study, we examined a wide variety of species for expression of S-opsin (blue sensitive) and M-/L-opsin (green-red sensitive) in retinal cones using two novel monoclonal antibodies specific for peptides from human opsins. Mouse, rat and hare did not express one of the investigated epitopes, but we could clearly prove existence of cones through peanut agglutinin labelling. Retinas of guinea pig, dog, wolf, marten, cat, roe deer, pig and horse were positive for S-opsin, but not for M-/L-opsin. Nevertheless all these species ...
A potential link between insulin resistance and iron overload disorder in browsing rhinoceroses investigated through the use of an equine model. Iron overload disorder afflicts captive rhinoceros but has not been documented in the wild. The specific cause for the disorder has not been identified but is likely associated with diet and management. Compared with wild counterparts, captive rhinoceros eat diets containing more iron, have greater fat stores, and exercise less. It has been suggested that the problem may be linked to development of insulin resistance in the captive population. Given that controlled experiments with sufficient numbers of rhinoceros are logistically not possible, an equine model was used to look for a relationsh...
Role of KCNQ2 and KCNQ3 genes in juvenile idiopathic epilepsy in Arabian foals. Juvenile idiopathic epilepsy (JIE) in Arabian foals resembles benign-familial neonatal convulsion (BFNC) syndrome, a rare idiopathic epilepsy of new-born humans. BFNC syndrome exhibits genetic heterogeneity, as has been hypothesised to occur in Arabian foals, and is known to be caused by mutations in the voltage-gated potassium channel subunit KCNQ2 and KCNQ3 genes. The close phenotypic characteristics of both Arabian foals and children suggest these epileptic syndromes are caused by the same genetic disorder. In horses, the KCNQ2 and KCNQ3 genes are located on the terminal region of chromosom...
Does the stimulus type influence horses’ performance in a quantity discrimination task? The ability to understand the relation between quantities has been documented in a wide range of species. Such quantity discrimination competences are commonly demonstrated by a choice of the larger quantity or numerosity in a two-choice task. However, despite their overall success, many subjects commit a surprisingly large number of errors even in simple discriminations such as 1 vs. 3. Recently, it had been suggested that this is a result of the testing procedure. When monkeys could choose between different quantities of edible rewards, they showed low-level success. If, however, they chose ...
Lateralized suckling in domestic horses (Equus caballus). Brain lateralization enables preferential processing of certain stimuli and more effective utilization of these stimuli in either the left or the right cerebral hemisphere. Horses show both motor and sensory lateralization patterns. Our aim was to determine whether a lateralized response could be detected in foals during the naturally side-biased behaviour, suckling. The foals' preferred suckling side could be the effect of either visual or motor lateralization. In the case of a visual lateralized response, foals are expected to suck more often from the mother's right side, so potential danger...
The horse as a model of naturally occurring osteoarthritis. Osteoarthritis (OA) is an important cause of pain, disability and economic loss in humans, and is similarly important in the horse. Recent knowledge on post-traumatic OA has suggested opportunities for early intervention, but it is difficult to identify the appropriate time of these interventions. The horse provides two useful mechanisms to answer these questions: 1) extensive experience with clinical OA in horses; and 2) use of a consistently predictable model of OA that can help study early pathobiological events, define targets for therapeutic intervention and then test these putative thera...
Locomotor Inhibition in Adult Horses Faced to Stressors: A Single Postpartum Experience May be Enough! 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...
Equine cellular therapy–from stall to bench to bedside? Pioneering clinical stem cell research is being performed in the horse, a recipient of cutting edge veterinary medicine as well as a unique animal model, paving the way for human medical applications. Although demonstrable progress has been made on the clinical front, in vitro characterization of equine stem cells is still in comparatively early stages. To translate the promising results of clinical stem cell therapy in the horse, advances must be made in the characterization of equine stem cells. Aiming to improve communication between veterinarians and other natural scientists, this review g...
Stem cell therapy of tendinopathies: suggestions from veterinary medicine. The ideal strategy for tendon healing has not been identified to date. Recently, the use of stem cells based therapy has been proposed, due to their ability to proliferate and to differentiate towards specific connective tissues lineages. Embryonic stem cells should be considered the ideal cell source for regenerative therapies, but ethical factors limit their use in humans. Mesenchymal stem cells are more easily available and can be obtained by different sources. Amnion derived stem cells can differentiate towards all three germ layers, and can be used for allogeneic transplantation and store...
Estimating variance components and predicting breeding values for eventing disciplines and grades in sport horses. Eventing competitions in Great Britain (GB) comprise three disciplines, each split into four grades, yielding 12 discipline-grade traits. As there is a demand for tools to estimate (co)variance matrices with a large number of traits, the aim of this work was to investigate different methods to produce large (co)variance matrices using GB eventing data. Data from 1999 to 2008 were used and penalty points were converted to normal scores. A sire model was utilised to estimate fixed effects of gender, age and class, and random effects of sire, horse and rider. Three methods were used to estimate (...
Object habituation in horses: the effect of voluntary versus negatively reinforced approach to frightening stimuli. 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...
Genetic (co)variance components across age for Show Jumping performance as an estimation of phenotypic plasticity ability in Spanish horses. The purpose of this study was to study phenotypic plasticity ability for Show Jumping performance in horses according to age differences. For this study, 11 352 participations, belonging to 1085 horses grouped by age (4-, 5- or 6-year olds), were analysed. repeatability animal models (RAM) and multiple trait animal models (MTAM) were compared. RAM assumed the same covariance components for all age groups, whereas MTAM considered the results of every animal at every age group as different (but correlated) traits. The age, sex, starting order and training level were included as fixed effects. T...
Neutrophils are not less sensitive than other blood leukocytes to the genomic effects of glucocorticoids. Neutrophils are generally considered less responsive to glucocorticoids compared to other inflammatory cells. The reported increase in human neutrophil survival mediated by these drugs partly supports this assertion. However, it was recently shown that dexamethasone exerts potent anti-inflammatory effects in equine peripheral blood neutrophils. Few comparative studies of glucocorticoid effects in neutrophils and other leukocytes have been reported and a relative insensitivity of neutrophils to these drugs could not be ruled out. Objective: We assessed glucocorticoid-responsiveness in equine an...
Mutations in DMRT3 affect locomotion in horses and spinal circuit function in mice. Locomotion in mammals relies on a central pattern-generating circuitry of spinal interneurons established during development that coordinates limb movement. These networks produce left-right alternation of limbs as well as coordinated activation of flexor and extensor muscles. Here we show that a premature stop codon in the DMRT3 gene has a major effect on the pattern of locomotion in horses. The mutation is permissive for the ability to perform alternate gaits and has a favourable effect on harness racing performance. Examination of wild-type and Dmrt3-null mice demonstrates that Dmrt3 is exp...
The isolated perfused equine distal limb as an ex vivo model for pharmacokinetic studies. Even though intra-articular injections play an important role in the treatment of joint-related lameness in horses, little is known about pharmacokinetic properties of substances used. Therefore, an ex vivo model for pharmacokinetic studies was developed using distal forelimbs of slaughtered horses. The extremity was perfused with gassed Tyrode solution for up to 8 h. Tissue viability was confirmed by measurements of glucose consumption, lactate production, and lactate dehydrogenase activity in the perfusate. Standard criteria for tissue viability had been determined in preliminary experiments...
Breeding or assisted reproduction? Relevance of the horse model applied to the conservation of endangered equids. Many wild equids are at present endangered in the wild. Concurrently, increased mechanization has pushed back the numbers of some old native horse breeds to levels that are no longer compatible with survival of the breed. Strong concerns arose in the last decade to preserve animal biodiversity, including that of rare horse breeds. Genome Resource Banking refers to the cryostorage of genetic material and is an approach for ex situ conservation, which should be applied in combination with in situ conservation programmes. In this review, we propose that, owing to the great reproductive similarity...
Development of a novel mucosal vaccine against strangles by supercritical enhanced atomization spray-drying of Streptococcus equi extracts and evaluation in a mouse model. Strangles is an extremely contagious and sometimes deadly disease of the Equidae. The development of an effective vaccine should constitute an important asset to eradicate this worldwide infectious disease. In this work, we address the development of a mucosal vaccine by using a Supercritical Enhanced Atomization (SEA) spray-drying technique. Aqueous solutions containing the Streptococcus equi extracts and chitosan were converted into nanospheres with no use of organic solvents. The immune response in a mouse model showed that the nanospheres induced a well-balanced Th1 and Th2 response charac...
The pathogenesis of tendon microdamage in athletes: the horse as a natural model for basic cellular research. The equine superficial digital flexor tendon (SDFT) is a frequently injured structure that is functionally and clinically equivalent to the human Achilles tendon (AT). Both act as critical energy-storage systems during high-speed locomotion and can accumulate exercise- and age-related microdamage that predisposes to rupture during normal activity. Significant advances in understanding of the biology and pathology of exercise-induced tendon injury have occurred through comparative studies of equine digital tendons with varying functions and injury susceptibilities. Due to the limitations of in-...
Comparative study of depth-dependent characteristics of equine and human osteochondral tissue from the medial and lateral femoral condyles. Articular cartilage defects are common after joint injuries. When left untreated, the biomechanical protective function of cartilage is gradually lost, making the joint more susceptible to further damage, causing progressive loss of joint function and eventually osteoarthritis (OA). In the process of translating promising tissue-engineering cartilage repair approaches from bench to bedside, pre-clinical animal models including mice, rabbits, goats, and horses, are widely used. The equine species is becoming an increasingly popular model for the in vivo evaluation of regenerative orthopaedic ap...
Correlations of unfavorable movement characteristics in warmblood foals and mares with routinely assessed conformation and performance traits. New movement traits reflecting unfavorable movement characteristics were defined on the basis of detailed movement evaluations (DME) of warmblood foals and mares performed in connection with regular breeding events of the Oldenburg horse breeding societies in 2009 and 2010. DME information was available for 3374 foals and 2844 mares and used for correlation analyses with conformation information on 1987 mares from studbook inspections (SBI) in 2009 and performance information on 2758 mares from mare performance tests (MPT) in 2000 to 2008. Analyses of variance revealed few significant differen...
Rutgers Young Horse Teaching and Research Program: undergraduate student outcomes. Equine teaching and research programs are popular but expensive components of most land grant universities. External funding for equine research, however, is limited and restricts undergraduate research opportunities that enhance student learning. In 1999, a novel undergraduate teaching and research program was initiated at Rutgers University, New Brunswick, NJ. A unique aspect of this program was the use of young horses generally considered "at risk" and in need of rescue but of relatively low value. The media interest in such horses was utilized to advantage to obtain funding for the program...
Rutgers Young Horse Teaching and Research Program: sustainability of taking a risk with “at risk” horses. In 1999, the Young Horse Teaching and Research Program (YHTRP) was initiated at Rutgers University. The unique aspect of the program was using horses generally considered "at risk" and in need of rescue, but of relatively low value. The risks of using horses from pregnant mare urine (PMU) ranches and Bureau of Land Management (BLM) mustangs were high, but, ultimately, unrealized. No students or staff members were seriously injured over the course of the next 12 yr, and the horses were sold annually as highly desirable potential athletes or pleasure horses, usually at a profit. The use of "at r...
RACK1, a clue to the diagnosis of cutaneous melanomas in horses. Melanocytic proliferations are common in horses but the diagnosis of malignancy is not always straightforward. To improve diagnosis and prognosis, markers of malignancy are needed. Receptor for activated C kinase 1 (RACK1) protein may be such a marker. RACK1 was originally found to characterize malignant melanocytic lesions in the Melanoblastoma-bearing Libechov minipig (MeLiM) and, later, in human patients. Our purpose was to investigate the value of RACK1 in the classification of cutaneous melanocytic proliferations in horses. Results: Using immunofluorescence, we report here that both MITF ...
Towards an ethological animal model of depression? A study on horses. Recent 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). Results: We observed the spontaneous behav...
Seroprevalence and risk factors associated to West Nile virus in horses from Andalusia, Southern Spain. West Nile virus (WNV) is recognized as an emerging zoonotic pathogen, whose incidence in horses, humans and birds has increased significantly in different European countries in the last decade. A serosurvey study was carried out in non vaccinated horses to determine the geographical distribution of WNV in Andalusia (Southern Spain), and to assess the factors that influence the risk of WNV infection in horses. Antibodies to WNV were detected in 54 out of 510 horses analyzed by a blocking ELISA, of which 36 were confirmed by micro virus neutralization test (7.1%; CI(95%): 4.9-9.3). A total of 28...
A few days of social separation affects yearling horses’ response to emotional reactivity tests and enhances learning performance. Learning performance is influenced by emotional reactivity, low reactivity being generally beneficial. Previous experiments show that emotional reactivity can be modified after a period of social isolation. We hypothesized that eleven days of isolation would affect yearlings' emotional reactivity and improve their learning abilities. Twenty-five yearlings were divided into two groups: 12 were continuously isolated for 11 days (isolated) and 13 stayed together (control). During the period of isolation, all yearlings underwent two learning tasks: a habituation procedure in which a novel object w...