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.
Prevalence of traumatic myiasis in Hungary: a questionnaire survey of veterinarians. Veterinarians in Hungary were asked to complete a questionnaire on traumatic myiasis; of the 664 veterinarians contacted, 247 replied (37.2 per cent) and of these 209 (84.6 per cent) reported myiasis to be a problem among the livestock they treated. Infestation levels of > 10 per cent of animals were reported in sheep, cattle and horses. The myiasis season lasted from March to November with most cases reported in July and August. Significantly more respondents reported that fly larvae were present deep in wounds rather than superficially, consistent with infestations due to the obligate parasi...
Equine SCID: mechanistic analysis and comparison with murine SCID. V(D)J rearrangement is the molecular mechanism by which an almost limitless number of unique immune receptors is generated. V(D)J rearrangement involves two DNA breaks and religations resulting in two DNA joints; coding and signal joints. If V(D)J recombination is impaired (as in murine SCID (C.B-17 mouse] or RAG [Recombinase Activating Genes) deficient mice), B lymphocyte and T lymphocyte development is blocked and severe immunodeficiency results. The first animal model of SCID was reported in Arabian foals in 1973. Recently we demonstrated that the mechanistic defect in SCID foals is V(D)J r...
Pathogenicity of Vibrio alginolyticus for cultured gilt-head sea bream (Sparus aurata L.). The in vivo and in vitro pathogenic activities of whole cells and extracellular products of Vibrio alginolyticus for cultured gilt-head sea bream were evaluated. The 50% lethal doses ranged from 5.4 x 10(4) to 1.0 x 10(6) CFU/g of body weight. The strains examined had the ability to adhere to skin, gill, and intestinal mucus of sea bream and to cultured cells of a chinook salmon embryo cell line. In addition, the in vitro ability of V. alginolyticus to adhere to mucus and skin cells of sea bream was demonstrated by scanning electron microscopy. The biological activities of extracellular produc...
Animal models of pneumocystosis. As in vitro culture systems allowing to isolate Pneumocystis samples from patients or other mammal hosts are still not available, animal models have critical importance in Pneumocystis research. The parasite was reported in numerous mammals but P. carinii pneumonia (PCP) experimental models were essentially developed by using rats, mice, rabbits and ferrets. The rat treated with corticosteroids for 9-12 weeks is a useful PCP model. Like laboratory rats, conventional mice develop PCP after prolonged corticosteroid administration. The ferret (Mustela putorius furo) also develop PCP under cortico...
[The variability and heritability of the indices of speed and exterior characters in horses of the Orlov trotter breed]. Study of the variability and heritability of sprightliness and exterior characteristics which are the constituent factors of capacity for work of trotting horse breed, permits predicting and planning the direction of selection work in the breed, and determining the efficiency of animals selection according to phenotype. To increase the level of capacity for work of Orloff trotting horse breed, according to the paper data, more consideration should be given to correctness of the exterior, as a biomechanical basis of the horse motion.
[Are zoo Przewalski horses domesticated horses?]. Analysed were the brain case capacities and brain weights of wild przewalski horses, przewalski horses from zoological gardens and domesticated horses. Domesticated horses have about 14% less brain case capacity and 16% less brain weight than wild przewalski horses. Przewalski horses from zoological gardens also have about 14% less brain capacity than wild przewalski horses. The brain weight of przewalski horses from zoological gardens shows no difference to the brain weight of domesticated horses. If we look at the brain size, przewalski horses from zoological gardens are domesticated horses....
Experimental model of synovitis/capsulitis in the equine metacarpophalangeal joint. To develop and define a model of acute synovitis/capsulitis in the equine metacarpophalangeal joint (fetlock) to study clinical effects of diagnostic or therapeutic procedures. Methods: 5 adult Standardbreds. Methods: Polyvinyl alcohol foam particles were injected into the left front fetlock of horses; the right front fetlock was used as a control. Horses were examined clinically and for lameness on a regular basis. Blood samples were taken to measure routine variables. Synovial fluid samples were collected from both fetlocks, and macroscopic, microscopic, and biochemical variables were measur...
Effect of bilateral blockade of the pharyngeal branch of the vagus nerve on soft palate function in horses. To determine the effect of bilateral blockade of the pharyngeal branch of the vagus nerve on soft palate function in horses. Methods: 5 Standardbreds. Methods: Peak tracheal inspiratory and expiratory pressures and airflow were measured while horses exercised at the speeds corresponding to 75 and 100% of the speed that resulted in maximal heart rate, with and without pharyngeal branch of the vagus nerve blockade. Respiratory frequency-to-stride frequency coupling ratio was measured by correlating foot fall measurements with respiratory frequency. The pharyngeal branch of the vagus nerve was bl...
Serologic survey for hantavirus infection in domestic animals and coyotes from New Mexico and northeastern Arizona. To determine whether animals had serologic evidence of infection with Sin Nombre virus (SNV). Methods: Prospective serosurvey. Methods: Serum samples were obtained from 145 cats, 85 dogs, 120 horses, and 24 cattle between April 1993 and August 1994 and 54 coyotes between December 1994 and February 1995. Methods: Serum samples were analyzed by western immunoblot assays for reaction with SNV nucleocapsid antigen. Samples with reactivity to SNV nucleocapsid proteins were used to probe multiple-antigen blots containing recombinant fusion proteins derived from prototypic hantaviruses. Lung tissue o...
Stability over situations in temperamental traits of horses as revealed by experimental and scoring approaches. Individual behavioural reactions of adult horses in a variety of experimental tests were compared with ratings by riding teachers. The tests were made in a non working situation, with the animals being released in an arena, a box (arena test, new object test, learning tests) or handled (new object/handling situation). The traits rated by teachers were fearfulness, nervousness, gregariousness and learning abilities at work (ridden or handled). Despite a great homogeneity in the reactions exhibited by the horses in the different situations, large individual differences were present. Correlations...
Head, face, and neck trauma from large animal injury in New Mexico. Head, face, and neck injuries (HFNI) occur during animal-related trauma. We compared patients with HFNI and without HFNI after animal-related injuries to determine the significance of these injuries. Methods: Retrospective review of admissions for animal injuries between January 1, 1990, and December 31, 1995, by age, gender, mechanism, animal, Glasgow Coma Scale (GCS) score, Injury Severity Score (ISS), Abbreviated Injury Severity score for head and neck (AIS Head/Neck), AIS score for face (AIS Face), intensive care unit stay, hospitalization length, morbidity, and mortality. Results: There w...
Stabilizing Selection and the Comparative Analysis of Adaptation. Comparative studies tend to differ from optimality and functionality studies in how they treat adaptation. While the comparative approach focuses on the origin and change of traits, optimality studies assume that adaptations are maintained at an optimum by stabilizing selection. This paper presents a model of adaptive evolution on a macroevolutionary time scale that includes the maintenance of traits at adaptive optima by stabilizing selection as the dominant evolutionary force. Interspecific variation is treated as variation in the position of adaptive optima. The model illustrates how phylog...
The pathogenesis of ED71, a defined deletion mutant of equine herpesvirus-1, in a murine intranasal infection model for equine abortion. A series of mutants of equine herpesvirus-1 (EHV-1) which contain deletions in non-essential genes was previously characterized in a murine intranasal infection model. One mutant, ED71 which was shown to be attenuated in the model, was further characterized by inoculation into pregnant mice. Despite the attenuation previously reported, intranasal inoculation of pregnant mice resulted in premature parturition and the birth of dead or dying foetuses. Furthermore, mice inoculated before pregnancy with the same mutant, and subsequently challenged 14 days after conception with wild-type virus, were...
Experimental tests to assess emotionality in horses. Different tests were used to assess different aspects of the emotionality of 1-3 year-old horses: arena test; a `novel object' test; and a handling test. In reaction to the test situations no important differences were observed according to age or sex in the behaviour patterns, but clear individual differences were observed within these classes. The arena test seemed to reveal the degree of gregariousness of the animals whereas the results in the two other tests were correlated and seemed to reflect an inherent degree of fearfulness in the horse. Indices were developed that enabled to rank the...
Antigenic polymorphism of the lipopolysaccharides from human and animal isolates of Bordetella bronchiseptica. Six monoclonal antibodies (mAbs) against lipopolysaccharides (LPS) from Bordetella pertussis (P1P3, 60.5), B. parapertussis (PP2, PP6, PPB) and B. bronchiseptica (BRg1) were used to examine the presence of antigenic determinants of LPS on B. bronchiseptica cells. Forty-eight clinical isolates of this Gram-negative bacterium (4 canine, 3 equine, 6 porcine, 4 rabbit and 31 human) were examined. Significant cross-reactivities with the heterologous anti-pertussis and anti-parapertussis mAbs were observed. The isolates also exhibited marked antigenic polymorphism. The 48 isolates could be classifie...
Consideration of the relevance of ethological animal models for human repetitive behavioral spectrum disorders. Treatment successes of various stereotyped behaviors in animals and humans has renewed interest in ethologic animal models for the study of psychiatric disorders. This report presents another such behavior occurring in horses to weaving. This anomalous, repetitive, and purposeless behavior draws analogies to human compulsive spectrum behaviors. A "weaver" provided an opportunity to evaluate serotonin, dopamine, and opioid neurotransmitter system contributions by probing each with a selective agent in A-B-A-C-A-D design. The horse was treated in sequential 1-month periods separated by 1-month w...
Alterations in equine guttural pouch morphology with head position: observations using a new technique for producing accurate casts. An improved technique for preparing casts of the equine guttural pouch is described. The new technique is simplified and inexpensive in comparison to previous techniques and produces highly accurate anatomic models which are both durable and flexible. Methods: Silicone rubber bathtub caulk was injected into the guttural pouches of horse cadavers. The silicone was allowed to cure overnight, and casts were removed by dissection. The new technique was then used to evaluate changes in the shape of the guttural pouch with changes in head position. Results: With flexion of the atlanto-occipital join...
The complete mitochondrial DNA (mtDNA) of the donkey and mtDNA comparisons among four closely related mammalian species-pairs. The nucleotide sequence of the complete mitochondrial genome of the donkey, Equus asinus, was determined. The length of the molecule is 16,670 bp. The length, however, is not absolute due to pronounced heteroplasmy caused by variable numbers of two types of repetitive motifs in the control region. The sequence of the repeats is (a) 5'-CACACCCA and (b) 5'-TGCGCGCA, respectively. The order of (a) and (b) can be expressed as {n[2(a)+(b)]+m(a)}. In 32 different clones analyzed the number of n and m ranged from 0 to 9 and 1 to 7. The two rRNA genes, the 13 peptide-coding genes, and the 22 tRNA gene...
Transmission of the South African asinine strain of equine arteritis virus (EAV) among horses and between donkeys and horses. Lateral and sexual transmission of EAV among horses and lateral transmission between donkeys and horses were attempted by experimental infection with the South African asinine strain. Clinical, immunological and virological responses were evaluated. All intramuscularly inoculated horses developed very mild clinical signs, were viraemic, shed virus from nasopharynx, and seroconverted. Lateral infection was demonstrated in one in-contact mare. Reinfection of two stallions by intranasal instillation was shown by virus recovery from buffy-coat cultures. After nasal instillation of virus, one stall...
Equine rhinovirus serotypes 1 and 2: relationship to each other and to aphthoviruses and cardioviruses. Equine rhinoviruses (ERVs) are picornaviruses which cause a mild respiratory infection in horses. The illness resembles the common cold brought about by rhinoviruses in humans; however, the presence of a viraemia during ERV-1 infection, the occurrence of persistent infections and the physical properties are all more reminiscent of foot-and-mouth disease virus (FMDV). cDNA cloning and sequencing of the genomes of ERV-1 and ERV-2 between the poly(C) and poly(A) tracts showed that the serotypes are heterogeneous. Nevertheless, the genomic architecture of both serotypes is most similar to that of ...
Heterologous antisera and antivenins are essential biologicals: perspectives on a worldwide crisis. Active immunization against infectious disease is important. However, much of our world faces poverty, social injustice, and warfare, all of which cause universal immunization to remain a distant dream. Agents that provide passive immunity thus remain essential biologicals. The most important of these are human or equine antisera against rabies, tetanus, diphtheria, and snake antivenins. Homologous products are either unavailable or unaffordable in places where they are needed the most. Less expensive heterologous (equine) antisera can be purified and are safe to use, but these antisera are al...
Evaluation of a biofragmentable anastomosis ring for small intestinal anastomosis in ponies. Six ponies divided into two groups of three were used in a double crossover study design. Group 1 ponies had a small intestinal resection and anastomosis performed using a biofragmentable anastomosis ring (BAR); group 2 ponies had a hand-sewn small intestinal resection and anastomosis using a Gambee suture pattern. Approximately 30 days later, all ponies had a second celiotomy and anastomosed segments were removed. Group 1 ponies had a hand-sewn anastomosis performed and group 2 had a BAR. The anastomotic sites were collected at necropsy approximately 30 days later. Anastomosed intestinal segm...