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.
Functional characterization of EUL47 in productive replication, morphogenesis and infectivity of equine herpesvirus 1. EUL47 is a major component of the tegument of equine herpesvirus 1 (EHV-1). To determine its function, we used Red/ET cloning to delete its gene (gene 13) from EHV-1 strain Ab4p inserted into a bacterial artificial chromosome (BAC), yielding Ab4pattBΔ13. We also examined the reverted virus (Ab4pattB13R). Ab4pattBΔ13 replicated in rabbit kidney (RK)-13 cells, indicating that ORF13 is dispensable for virus replication in cell culture. Its intracellular and extracellular titers were about 10- and 100-fold lower than those of the revertant and parent strains, respectively. In addition, the plaqu...
A genome-wide association study for quantitative trait loci of show-jumping in Hanoverian warmblood horses. Show-jumping is an economically important breeding goal in Hanoverian warmblood horses. The aim of this study was a genome-wide association study (GWAS) for quantitative trait loci (QTL) for show-jumping in Hanoverian warmblood horses, employing the Illumina equine SNP50 Beadchip. For our analyses, we genotyped 115 stallions of the National State stud of Lower Saxony. The show-jumping talent of a horse includes style and ability in free-jumping. To control spurious associations based on population stratification, two different mixed linear animal model (MLM) approaches were employed, besides l...
Hypoxic ischemic encephalopathy–what can we learn from humans? Hypoxic ischemic encephalopathy (HIE) is a condition that occurs in both human newborns and foals. The condition is the subject of extensive current research in human infants, but there have been no direct studies of HIE in foals, and hence, knowledge of the condition has been extrapolated from studies in humans and other animal models. The purpose of this review article is to highlight the most up-to-date and relevant research in the human field, and discuss how this potentially might have an impact in the management of foals with HIE.
Characterization of cytokines associated with Th17 cells in the eyes of horses with recurrent uveitis. Equine recurrent uveitis (ERU) is a spontaneous disease that is the most common cause of blindness in horses, affecting up to 15% of the horse population. Th17 cells are a major cell population driving the pathogenesis in several mouse models of autoimmune inflammation, including experimental autoimmune uveitis. The purpose of this study is to investigate the role a Th17 cell-mediated response plays in the pathogenesis of ERU. Methods: Banked, Davidson's-fixed equine globes histopathologically diagnosed with ERU (n = 7) were compared immunohistochemically with healthy control globes (n = 7). I...
Network simulation modeling of equine infectious anemia in the non-racehorse population in Japan. An equine infectious anemia (EIA) transmission model was developed by constructing a network structure of horse movement patterns in a non-racehorse population. This model was then used to evaluate the effectiveness and efficiency of several EIA surveillance strategies. Because EIA had not been detected in Japan since 1993, it was appropriate to review the current surveillance strategy, which aims to eradicate EIA by intensive testing, and to consider alternative strategies suitable for the current EIA status in Japan. The non-racehorse population was divided into four sectors based on horse u...
The same ELA class II risk factors confer equine insect bite hypersensitivity in two distinct populations. Insect bite hypersensitivity (IBH) is a chronic allergic dermatitis common in horses. Affected horses mainly react against antigens present in the saliva from the biting midges, Culicoides ssp, and occasionally black flies, Simulium ssp. Because of this insect dependency, the disease is clearly seasonal and prevalence varies between geographical locations. For two distinct horse breeds, we genotyped four microsatellite markers positioned within the MHC class II region and sequenced the highly polymorphic exons two from DRA and DRB3, respectively. Initially, 94 IBH-affected and 93 unaffected Sw...
Functional electrical stimulation of intrinsic laryngeal muscles under varying loads in exercising horses. Bilateral vocal fold paralysis (BVCP) is a life threatening condition and appears to be a good candidate for therapy using functional electrical stimulation (FES). Developing a working FES system has been technically difficult due to the inaccessible location and small size of the sole arytenoid abductor, the posterior cricoarytenoid (PCA) muscle. A naturally-occurring disease in horses shares many functional and etiological features with BVCP. In this study, the feasibility of FES for equine vocal fold paralysis was explored by testing arytenoid abduction evoked by electrical stimulation of t...
Heaves, an asthma-like disease of horses. Animal models have been developed to investigate specific components of asthmatic airway inflammation, hyper-responsiveness or remodelling. However, all of these aspects are rarely observed in the same animal. Heaves is a naturally occurring disease of horses that combines these features. It is characterized by stable dust-induced inflammation, bronchospasm and remodelling. The evaluation of horses during well-controlled natural antigen exposure and avoidance in experimental settings allows the study of disease mechanisms in the asymptomatic and symptomatic stages, an approach rarely feasible ...
Assessment of quality of life in equine patients. Assessing patients' quality of life (QOL) is a core part of clinical decision making. Various methodologies for assessing patients' QOL have been developed in human medicine and small animal veterinary disciplines. In contrast, the lack of aids for QOL assessment in equine veterinary practice leaves practitioners reliant on subjective assessments of QOL, which may be prone to avoidable errors. Objective: This paper suggests pragmatic ways in which QOL may be enhanced, while remaining appropriate for the time, financial and owner-based constraints within equine practice. Methods: Through interd...
Evaluation of primary epidermal lamellar density in the forefeet of near-term fetal Australian feral and domesticated horses. To investigate the density of the primary epidermal lamellae (PEL) around the solar circumference of the forefeet of near-term fetal feral and nonferal (ie, domesticated) horses. Methods: Left forefeet from near-term Australian feral (n = 14) and domesticated (4) horse fetuses. Methods: Near-term feral horse fetuses were obtained from culled mares within 10 minutes of death; fetuses that had died in utero 2 weeks prior to anticipated birth date and were delivered from live Thoroughbred mares were also obtained. Following disarticulation at the carpus, the left forefoot of each fetus was frozen...
The evolutionary origins of friendship. Convergent evidence from many species reveals the evolutionary origins of human friendship. In horses, elephants, hyenas, dolphins, monkeys, and chimpanzees, some individuals form friendships that last for years. Bonds occur among females, among males, or between males and females. Genetic relatedness affects friendships. In species where males disperse, friendships are more likely among females. If females disperse, friendships are more likely among males. Not all friendships, however, depend on kinship; many are formed between unrelated individuals. Friendships often involve cooperative inte...
A recombinant Hendra virus G glycoprotein-based subunit vaccine protects ferrets from lethal Hendra virus challenge. The henipaviruses, Hendra virus (HeV) and Nipah virus (NiV), are two deadly zoonotic viruses for which no vaccines or therapeutics have yet been approved for human or livestock use. In 14 outbreaks since 1994 HeV has been responsible for multiple fatalities in horses and humans, with all known human infections resulting from close contact with infected horses. A vaccine that prevents virus shedding in infected horses could interrupt the chain of transmission to humans and therefore prevent HeV disease in both. Here we characterise HeV infection in a ferret model and show that it closely mirror...
Evidence-based medicine in bovine, equine and canine reproduction: quality of current literature. The objective was to evaluate deficits and differences of published literature on reproduction in cattle, horses, and dogs. A literature search was conducted in the databases Medline and Veterinary Science. Approximately five times more articles on clinical bovine reproduction (n = 25 910) were found compared to canine (n = 5 015) and equine (n = 5 090) reproduction. For the evaluation of the literature, a checklist was used. A subset of 600 articles published between 1999 and 2008 was randomly selected. After applying exclusion criteria, a total of 268 trials (86 for cattle, 99 for horses, an...
The role of working equines to livelihoods in current day campesino hill-slope communities in central Mexico. Small-holder campesino agriculture is based on the diversified use of resources and off-farm work. Working equines have a multifunctional character and sustain the diversification of livelihoods having different values as assets or providing services. The objective was to identify the role of working equines in current diversification strategies in the livelihoods of campesino families in a hill-slope community in central Mexico within livelihoods analysis. Thirty-one variables related to ownership and use of working equines were analysed by cluster analysis and descriptive statistics contrast...
Distances travelled by feral horses in ‘outback’ Australia. The distance travelled by Australian feral horses in an unrestricted environment has not previously been determined. It is important to investigate horse movement in wilderness environments to establish baseline data against which the movement of domestically managed horses and wild equids can be compared. Objective: To determine the travel dynamics of 2 groups of feral horses in unrestricted but different wilderness environments. Methods: Twelve feral horses living in 2 wilderness environments (2000 vs. 20,000 km(2)) in outback Australia were tracked for 6.5 consecutive days using custom desi...
Dynamic mobilisations in cervical flexion: Effects on intervertebral angulations. Based upon human data, it is probable that many conditions associated with neck pain in horses may benefit from performing mobilisation exercises as part of the rehabilitation protocol. Objective: To compare sagittal plane intervertebral angulations in a neutral standing position with the angulations at end range of motion in 3 dynamic mobility exercises performed in cervical flexion. Methods: Sagittal plane motion of the head, neck and back were measured in 8 sound horses standing in a neutral position and in 3 end-of-range neck flexion positions: chin-to-chest, chin-between-carpi, and chin-b...
Rabbit anti-rabies immunoglobulins production and evaluation. Due to the disadvantages of human and equine rabies immunoglobulin, it is necessary to develop a substitute for HRIG and ERIG, especially for those people living in the developing countries. Because of higher affinity and lower immunogenicity of rabbit's immunoglobulins, anti-rabies immunoglobulins specific to rabies virus were produced in rabbits as a bioreactor, and had been characterized by ELISA, affinity assay, immunofluorescence assay (IFA), immunocytochemistry, rapid fluorescent focus inhibition test (RFFIT). ELISA, affinity assay and IFA showed that rabbit RIG (RRIG) bound specifically...
The role of RTX toxins in host specificity of animal pathogenic Pasteurellaceae. RTX toxins are bacterial pore-forming toxins that are particularly abundant among pathogenic species of Pasteurellaceae, in which they play a major role in virulence. RTX toxins of several primary pathogens of the family of Pasteurellaceae are directly involved in causing necrotic lesions in the target organs. Many RTX toxins are known as haemolysins because they lyse erythrocytes in vitro, an effect that is non-specific, but which serves as a useful marker in bacteriological identification and as an easily measurable signal in vitro in experimental studies. More recent studies have shown that...
Adaptive molecular evolution of the Major Histocompatibility Complex genes, DRA and DQA, in the genus Equus. Major Histocompatibility Complex (MHC) genes are central to vertebrate immune response and are believed to be under balancing selection by pathogens. This hypothesis has been supported by observations of extremely high polymorphism, elevated nonsynonymous to synonymous base pair substitution rates and trans-species polymorphisms at these loci. In equids, the organization and variability of this gene family has been described, however the full extent of diversity and selection is unknown. As selection is not expected to act uniformly on a functional gene, maximum likelihood codon-based models o...
Geometric morphometrics as a tool for improving the comparative study of behavioural postures. Describing postures has always been a central concern when studying behaviour. However, attempts to compare postures objectively at phylogenetical, populational, inter- or intra-individual levels generally either rely upon a few key elements or remain highly subjective. Here, we propose a novel approach, based on well-established geometric morphometrics, to describe and to analyse postures globally (i.e. considering the animal's body posture in its entirety rather than focusing only on a few salient elements, such as head or tail position). Geometric morphometrics is concerned with describing ...
Protective effects of broadly neutralizing immunoglobulin against homologous and heterologous equine infectious anemia virus infection in horses with severe combined immunodeficiency. Using the equine infectious anemia virus (EIAV) lentivirus model system, we previously demonstrated protective effects of broadly neutralizing immune plasma in young horses (foals) with severe combined immunodeficiency (SCID). However, in vivo selection of a neutralization-resistant envelope variant occurred. Here, we determined the protective effects of purified immunoglobulin with more potent broadly neutralizing activity. Overall, protection correlated with the breadth and potency of neutralizing activity in vitro. Four of five SCID foals were completely protected against homologous challen...
Toxic equine parkinsonism: an immunohistochemical study of 10 horses with nigropallidal encephalomalacia. Chronic ingestion of yellow star thistle (Centaurea solstitialis) or Russian knapweed (Acroptilon repens) causes nigropallidal encephalomalacia (NPE) in horses with an abrupt onset of neurologic signs characterized by dystonia of lips and tongue, inability to prehend food, depression, and locomotor deficits. The objectives of this study were to reexamine the pathologic alterations of NPE and to conduct an immunohistochemistry study using antibodies to tyrosine hydroxylase and α-synuclein, to determine whether NPE brains show histopathologic features resembling those in human Parkinson disease...
In-vitro hypocoagulability on whole blood thromboelastometry associated with in-vivo expansion of red cell mass in an equine model. In several species, there is a strong correlation between indicators of red cell mass (RCM) and thromboelastometry results. The horse has a reliable, temporary, polycythemia in response to phenylephrine infusion. Our objective was to evaluate the effects of an in-vivo increase in circulating RCM on thromboelastometry results in an equine model of transient polycythemia. Six healthy research horses had whole blood thromboelastometry with contact activator and tissue factor initiation after recalcification of citrated samples. Additional samples were frozen for thrombin-antithrombin (TAT). Compl...
Do horses have a concept of person? Animals' ability for cross-modal recognition has recently received much interest. Captive or domestic animals seem able to perceive cues of human attention and appear to have a multisensory perception of humans. Results: Here, we used a task where horses have to remain immobile under a vocal order to test whether they are sensitive to the attentional state of the experimenter, but also whether they behave and respond differently to the familiar order when tested by a familiar or an unknown person. Horses' response varied according to the person's attentional state when the order was given by a...
Insulin resistance in equine digital vessel rings: an in vitro model to study vascular dysfunction in equine laminitis. One of the causes of equine laminitis is hyperinsulinaemia, which may be associated with endothelial dysfunction and insulin resistance of vessels. Objective: Insulin resistance can be induced in palmar digital vessels by continued exposure to insulin in vitro. The objective was to evaluate this in vitro model for future studies. Methods: Palmar digital vessel segments were collected immediately after euthanasia from horses with normal insulin/glucose blood values. Four arterial and 4 venous rings (3 mm wide) were prepared and each ring mounted in a tissue bath, containing Tyrode's solution at...
Spread of West Nile virus in Iran: a cross-sectional serosurvey in equines, 2008-2009. We report the first large-scale serosurvey for West Nile virus (WNV) conducted in the equine population in Iran. Blood samples were obtained in 2008-2009 from 1054 equines collected from 260 districts located in 27 provinces. The overall seroprevalence rate for WNV neutralizing antibodies was 23·7%. Marked geographical variations were observed as province-specific seroprevalence rates ranged from 1% to 88%, the highest values being observed in the southern and western parts of the country. The presence of IgM-positive animals (n=9) indicated a recent circulation of WNV in several provinces. L...
Induced pluripotent stem cell lines derived from equine fibroblasts. The domesticated horse represents substantial value for the related sports and recreational fields, and holds enormous potential as a model for a range of medical conditions commonly found in humans. Most notable of these are injuries to muscles, tendons, ligaments and joints. Induced pluripotent stem (iPS) cells have sparked tremendous hopes for future regenerative therapies of conditions that today are not possible to cure. Equine iPS (EiPS) cells, in addition to bringing promises to the veterinary field, open up the opportunity to utilize horses for the validation of stem cell based therapi...