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.
Donkey and Mule Welfare. Donkeys and mules have been critical to the development of human civilization, since being domesticated some 6000 years ago. However, they suffer from being undervalued or ignored by development agencies and animal protection nongovernmental organizations. Where they are recognized as affecting agriculture and the economy it is often because they are seen as being either invasive pests or an anachronism in the developing countries of the twenty-first century. Even in the wealthier societies of the world, donkeys suffer from ignorance about their proper management or a booming industry in heal...
Influence of digital hypothermia on lamellar events related to IL-6/gp130 signalling in equine sepsis-related laminitis. Interleukin-6 (IL-6) is consistently increased in the digital lamellae in different studies of sepsis-related laminitis (SRL). IL-6 signalling through the gp130 receptor activates similar signalling (i.e. mTORC1-related signalling) previously reported to be activated in models of endocrinopathic laminitis. Objective: To assess the activation state of signalling proteins downstream of IL-6/gp130 receptor complex activation in an experimental model of SRL. Methods: Randomised experimental study. Methods: Lamellar phospho-(P) protein concentrations downstream of the IL-6/gp130 receptors were asse...
Telomere regulation: lessons learnt from mice and men, potential opportunities in horses. Telomeres are genetically conserved nucleoprotein complexes located at the ends of chromosomes that preserve genomic stability. In large mammals, somatic cell telomeres shorten with age, owing to the end replication problem and lack of telomere-lengthening events (e.g. telomerase and ALT activity). Therefore, telomere length reflects cellular replicative reserve and mitotic potential. Environmental insults can accelerate telomere attrition in response to cell division and DNA damage. As such, telomere shortening is considered one of the major hallmarks of ageing. Much effort has been dedicate...
Longitudinal study of electrical, functional and structural remodelling in an equine model of atrial fibrillation. Large animal models are important in atrial fibrillation (AF) research, as they can be used to study the pathophysiology of AF and new therapeutic approaches. Unlike other animal models, horses spontaneously develop AF and could therefore serve as a bona fide model in AF research. We therefore aimed to study the electrical, functional and structural remodelling caused by chronic AF in a horse model. Nine female horses were included in the study, with six horses tachypaced into self-sustained AF and three that served as a time-matched sham-operated control group. Acceleration in atrial fibrilla...
Seroprevalence of Toxoplasma gondii in horses: A global systematic review and meta-analysis. Toxoplasmosis, one of the most common zoonoses worldwide, is caused by Toxoplasma gondii. T. gondii can infect almost all warm-blooded animals, including humans. Horses are an intermediate host of T. gondii, representing a potential risk for humans. To determine the T. gondii seroprevalence in horses worldwide, a global meta-analysis was conducted. A total of 35 publications were obtained by searching the PubMed, ScienceDirect, Chinese Web of knowledge (CNKI) and Wanfang databases. A total of 12,354 horses were assessed, of which 1580 were positive for T. gondii. The pooled overall seroprevale...
Comparative Review of Asthma in Farmers and Horses. Farmers are routinely exposed to organic dusts and aeroallergens that can have adverse respiratory health effects including asthma. Horses are farm-reared large animals with similar exposures and can develop equine asthma syndrome (EAS). This review aims to compare the etiology, pathophysiology, and immunology of asthma in horses compared to farmers and highlights the horse as a potential translational animal model for organic dust-induced asthma in humans. Severe EAS shares many clinical and pathological features with various phenotypes of human asthma including allergic, non-allergic, late o...
Equine Stereotaxtic Population Average Brain Atlas With Neuroanatomic Correlation. There is growing interest in the horse for behavioral, neuroanatomic and neuroscientific research due to its large and complex brain, cognitive abilities and long lifespan making it neurologically interesting and a potential large animal model for several neuropsychological diseases. Magnetic resonance imaging (MRI) is a powerful neuroscientific research tool that can be performed , with adapted equine facilities, or in the research setting. The brain atlas is a fundamental resource for neuroimaging research, and have been created for a multitude animal models, however, none currently exist f...
Genetic parameters and estimated breeding values for traits of raw and frozen-thawed semen in German Warmblood stallions. Objectives of the present study were to estimate genetic parameters for frozen-thawed semen traits of 271 fertile German Warmblood stallions and genetic correlations with raw semen quality traits. Semen samples were collected from stallions utilized for semen collection and artificial insemination (AI) on the Lower Saxon National Stud Celle and the North Rhine-Westphalian National Stud Warendorf. Semen quality variables were analyzed in 63,972 raw (gel-free volume, concentration, progressive motility, number of sperm) and 3681 frozen-thawed samples (motility, DNA fragmentation index (DFI), non...
Signatures of selection in the genome of Swedish warmblood horses selected for sport performance. A growing demand for improved physical skills and mental attitude in modern sport horses has led to strong selection for performance in many warmblood studbooks. The aim of this study was to detect genomic regions with low diversity, and therefore potentially under selection, in Swedish Warmblood horses (SWB) by analysing high-density SNP data. To investigate if such signatures could be the result of selection for equestrian sport performance, we compared our SWB SNP data with those from Exmoor ponies, a horse breed not selected for sport performance traits. Results: The genomic scan for homoz...
How do horses (Equus caballus) learn from observing human action? A previous study demonstrated that horses can learn socially from observing humans, but could not draw any conclusions about the social learning mechanisms. Here we develop this by showing horses four different human action sequences as demonstrations of how to press a button to open a feed box. We tested 68 horses aged between 3 and 12 years. 63 horses passed the habituation phase and were assigned either to the group Hand Demo (N = 13) for which a kneeling person used a hand to press the button, Head Demo (N = 13) for which a kneeling person used the head, Mixed Demo (N = 12) fo...
Estimation of the incidence of animal rabies in Punjab, India. Rabies is a devastating zoonotic disease of mammals that causes encephalitis and death. It is endemic in India, with an estimated annual 20,000 human deaths (one-third of the global rabies burden). The magnitude of animal rabies incidence is unknown. In four sub-districts of Punjab, India, we monitored canine and livestock populations from August 15, 2016 to August 14, 2017. Demographic, clinical and rabies diagnostic laboratory (RDL) data were collected from suspected cases of rabies. The annual incidence rate / 10,000 animal years at risk (95% CI) in each sub-district was estimated for each ...
Antigenicity assessment of the Theileria equi merozoite antigen (EMA-2) expressed in Pichia pastoris in mice and horses. Equine theileriosis is a severe equine disease caused by the protozoan Theileria equi, which is prevalent in tropical and subtropical areas. In this study, a recombinant equi merozoite antigen-2 (rEMA-2) of T. equi was used as an immunogen. Two groups of 10 mice each were divided into control and vaccinated groups. Sixty mares seronegative for theileriosis were divided in two groups, one vaccinated and another group as a control animal. Mice and mares of the vaccinated groups were inoculated with 150 μL of the vaccine containing 50 μg of rEMA-2 and 2 mL of the vaccine containing 200 ...
Mutual interactions between cognition and welfare: The horse as an animal model. Research in cognitive psychology has repeatedly shown how much cognition and emotions are mutually related to one another. Psychological disorders are associated with cognitive (attention, memory and judgment) biases and chronic pain may affect attention, learning or memory. Laboratory studies have provided useful insights about the processes involved but observations about spontaneous animal models, living in different stress/welfare conditions may help understand further how cognition and welfare are interrelated in the « real world ». Domestic horses constitute such a model as they live i...
Does Juvenile Play Programme the Equine Musculoskeletal System? In mammals, play behaviour appears innate and, because of this, may provide insight into the frequency and intensity of load that is required to stimulate positive musculoskeletal development. The objective of this review was to explore the interaction between play and tissue (bone) development at a molecular through to whole-animal level, with specific focus on the horse as a model. The basis of our understanding of the response of bone to loading is the mechanostat theorem. This assumes that at a tissue level, bone attempts to keep localised strain within the physiological range of 1500-2500...
Age-associated telomere shortening in Thoroughbred horses. Telomeres are genetically conserved repetitive terminal DNA that protect against genomic instability and shorten with ageing. Here, we reveal the leukocyte telomere length of Equus caballus by measuring terminal restriction fragments (TRFs) using Southern Blot analysis in a cohort of 43 Thoroughbred horses (age: 24 h-25 years). Heterogeneous TRFs were observed in each animal and large inter-animal variation in mean TRF was observed (range: 10.5-18.7 kbp). Mean TRFs were inversely correlated with age (r = -0.47). The estimated yearly rate of telomere attrition was 134 bp. Horses shoul...
Approach to Strain Selection and the Propagation of Viral Stocks for Venezuelan Equine Encephalitis Virus Vaccine Efficacy Testing under the Animal Rule. Licensure of a vaccine to protect against aerosolized Venezuelan equine encephalitis virus (VEEV) requires use of the U.S. Food and Drug Administration (FDA) Animal Rule to assess vaccine efficacy as human studies are not feasible or ethical. An approach to selecting VEEV challenge strains for use under the Animal Rule was developed, taking into account Department of Defense (DOD) vaccine requirements, FDA Animal Rule guidelines, strain availability, and lessons learned from the generation of filovirus challenge agents within the Filovirus Animal Nonclinical Group (FANG). Initial down-selectio...
Large Animal Models for the Clinical Application of Human Induced Pluripotent Stem Cells. Induced pluripotent stem cell (iPSC) technology offers a practically infinite and ethically acceptable source to obtain a variety of somatic cells. Coupled with the biotechnologies of cell therapy or tissue engineering, iPSC technology will enormously contribute to human regenerative medicine. Before clinical application, such human iPSC (hiPSC)-based therapies should be assessed using large animal models that more closely match biological or biomechanical properties of human patients. Therefore, it is critical to generate large animal iPSCs, obtain their iPSC-derived somatic cells, and precli...
Experimental and theoretical studies into the release of blood droplets from weapon tips. The formation and release under gravity of blood droplets from simulated weapon tips has been investigated experimentally and the results analysed and interpreted using established theoretical models for detached pendent drops. Droplets were produced from a series of conical nozzles, manufactured with a range of cone angles and including a set of un-bored conical tips, under conditions where the tip was either non-wetted or pre-wetted with blood. For the former, radius-limited case, detached droplet volumes were found to agree well with the predictions of both the pendent drop weight and drop ...
An Equine Wound Model to Study Effects of Bacterial Aggregates on Wound Healing. Objective: Relevant animal models to study effects of bacterial aggregates on wound healing are lacking. We aimed at establishing an equine wound model with bacterial aggregates to investigate the impact of bacterial inoculation on normal (thorax) and impaired (limb) wound healing. Approach: Wounds were created on three limbs and both thorax sides of six horses. Twelve out of 20 wounds per horse were inoculated with 104 Staphylococcus aureus and 105 Pseudomonas aeruginosa on day 4. Healing was monitored until day 27 by clinical assessment, including wound scoring, surface pH measurements, and ...
Equine or porcine synovial fluid as a novel ex vivo model for the study of bacterial free-floating biofilms that form in human joint infections. Bacterial invasion of synovial joints, as in infectious or septic arthritis, can be difficult to treat in both veterinary and human clinical practice. Biofilms, in the form of free-floating clumps or aggregates, are involved with the pathogenesis of infectious arthritis and periprosthetic joint infection (PJI). Infection of a joint containing an orthopedic implant can additionally complicate these infections due to the presence of adherent biofilms. Because of these biofilm phenotypes, bacteria within these infected joints show increased antimicrobial tolerance even at high antibiotic concentr...
Horses associate individual human voices with the valence of past interactions: a behavioural and electrophysiological study. Brain lateralization is a phenomenon widely reported in the animal kingdom and sensory laterality has been shown to be an indicator of the appraisal of the stimulus valence by an individual. This can prove a useful tool to investigate how animals perceive intra- or hetero-specific signals. The human-animal relationship provides an interesting framework for testing the impact of the valence of interactions on emotional memories. In the present study, we tested whether horses could associate individual human voices with past positive or negative experiences. Both behavioural and electroencephalo...
Description of Placement Procedures for Common Methods Used in Equine Emergency Rescue Using a Simplified Loops System. Entrapped, stranded and recumbent equids often require emergency rescue. The success of the rescue is often affected by secondary injuries from struggling of the horse to rise and from injury secondary to attempted rescue by pulling on the head or limbs of the equid. Therefore, having ready access to simplified rescue equipment which can be easily applied would be desirable. The devices currently available for these manipulations are not always readily available at the site of an incident. Here, we describe and illustrate the step-by-step use of a Loops System consisting of 183 cm round slings...
EHV-1 Pathogenesis: Current in vitro Models and Future Perspectives. Primary infection and pathogenesis of equine herpesvirus type 1 (EHV-1) require an intricate interaction of virus with the mucosal epithelium, mononuclear cells and the vascular endothelium. Studies on EHV-1 have been facilitated by the development of different models that recapitulate the tissue complexity. The available assays can be categorized into (i) models mimicking the epithelium-peripheral blood mononuclear cell (PBMC) interaction, which include mucosal (nasal and vaginal) explants and equine respiratory epithelial cells (EREC) cultures; and (ii) PBMC-endothelium mimicking models,...
Wound Photobiomodulation Treatment Outcomes in Animal Models. The possibilities that photobiomodulation has brought on to the medical field are ever expanding and the scope it has reached is infinite. Determining how this relatively new treatment technique can be incorporated into the veterinary medical field is of interest to many medical professionals. In this review, we examine the treatment outcomes of low-level-laser therapy (LLLT) in different animal models to pinpoint any similarities between the studies. A search was conducted to identify LLLT studies using different animal models with an open or closed wound. The studies were compared to identif...
Horses prefer to solicit a person who previously observed a food-hiding process to access this food: A possible indication of attentional state attribution. Inferring what others witnessed provides important benefits in social contexts, but evidence remains scarce in nonhuman animals. We investigated this ability in domestic horses by testing whether they could discriminate between two experimenters who differed in what they previously witnessed and decide whom to solicit when confronted with an unreachable food source based on that information. First, horses saw food being hidden in a closed bucket (impossible for them to open) in the presence of two experimenters who behaved identically but differed in their attention to the baiting process (the...
Heart rate variability parameters as markers of the adaptation to a sealed environment (a hypoxic normobaric chamber) in the horse. Simulated hypoxic normobaric devices have been used in human beings in order to enhance endurance capacity. These devices are sealed chambers where the athletes are supposed to stay for at least 6-8 hr daily. The current research assesses the changes in time-domain, spectral and non-geometrical heart rate variability (HRV) parameters in 6 horses subjected to progressive duration periods inside of a hermetically sealed chamber. It was pursued, firstly to evaluate the intensity of the stress experienced by the animals and secondly to elucidate whether the horses might require an acclimation per...
T2* and quantitative susceptibility mapping in an equine model of post-traumatic osteoarthritis: assessment of mechanical and structural properties of articular cartilage. To investigate the potential of quantitative susceptibility mapping (QSM) and T2* relaxation time mapping to determine mechanical and structural properties of articular cartilage via univariate and multivariate analysis. Samples were obtained from a cartilage repair study, in which surgically induced full-thickness chondral defects in the stifle joints of seven Shetland ponies caused post-traumatic osteoarthritis (14 samples). Control samples were collected from non-operated joints of three animals (6 samples). Magnetic resonance imaging (MRI) was performed at 9.4 T, using a 3-D multi-echo gr...
The Impact of Equine-Assisted Therapy on Equine Behavioral and Physiological Responses. Equine-assisted therapies (EATs) have been widely used in the treatment of patients with mental or physical conditions. However, studies on the influence of equine-assisted therapy (EAT) on equine welfare are very recent, and the need for further research is often highlighted. The aim of this study was to investigate whether EAT creates negative or positive emotions in horses, and the influence of patients' expectations (one group of patients had physical and psychological expectations and one group of patients had only psychological expectations) on horses' emotional responses. Fifty-eight pa...
Behavioral and Physiological Differences between Working Horses and Chilean Rodeo Horses in a Handling Test. Non-invasive measures are preferred when assessing animal welfare. Differences in behavioral and physiological responses toward a stressor could be the result of the selection of horses for specific uses. Behavioral and physiological responses of working and Chilean rodeo horses subjected to a handling test were assessed. Five behaviors, number of attempts, and the time to cross a bridge were video recorded and analyzed with the Observer XT software. Heart rate (HR) and heart rate variability (HRV), to assess the physiological response to the novel stimulus, were registered with a Polar Equine...