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Topic:Equine model

The equine model refers to the use of horses as a biological model in scientific research to study various physiological and pathological processes. Horses are utilized in research due to their unique physiological characteristics, which can parallel certain aspects of human health and disease. This model is applied in studies ranging from musculoskeletal disorders and respiratory diseases to metabolic syndromes and reproductive health. Research involving equine models often investigates disease mechanisms, therapeutic interventions, and preventative strategies. This page gathers peer-reviewed research studies and scholarly articles that explore the application, benefits, and limitations of using horses as models in scientific research, providing insights into equine and comparative biomedical studies.
Species differences in GnRH activation of the LHbeta promoter: role of Egr1 and Sp1.
Molecular and cellular endocrinology    June 1, 2002   Volume 189, Issue 1-2 85-96 doi: 10.1016/s0303-7207(01)00744-4
Call GB, Wolfe MW.Activation of the luteinizing hormone beta (LHbeta) promoter by gonadotropin-releasing hormone (GnRH) via the transcription factor early growth response protein-1 (Egr1) has been well characterized. To determine the mechanisms affecting Egr1 regulation of LHbeta, we analyzed five different species of LHbeta promoters (equine, mouse, rat, bovine and human). Electrophoretic mobility shift assays (EMSAs) identified multiple transcription factors binding to the Egr regions on the LHbeta promoter. Species-specific differences existed in the binding affinity for Sp1, Sp3, steroidogenic factor-1 (SF-...
Of patients & horses. Equine-facilitated psychotherapy.
Journal of psychosocial nursing and mental health services    May 23, 2002   Volume 40, Issue 5 16-19 doi: 10.3928/0279-3695-20020501-14
Bates A.1. Horses, just by their large, gentle presence, put people therapeutically in touch with the vitality of being alive. 2. People who ordinarily shun physical and emotional closeness often can accept closeness from a horse and through therapy can transfer these skills to their daily lives. 3. The behavior of a sensitive horse display the rider's emotions to the therapist and provides a vehicle the therapist can use to teach the patient coping skills. 4. Therapists with an interest in horses can learn more about how to become involved in an equine-facilitated psychotherapy practice through the N...
The equine hypophysis: a gland for all seasons.
Reproduction, fertility, and development    May 10, 2002   Volume 13, Issue 7-8 591-597 doi: 10.1071/rd01066
Tortonese DJ, Gregory SJ, Eagle RC, Sneddon CL, Young CL, Townsend J.The intrahypophysial mechanisms involved in the control of gonadotrophin secretion remain unclear. In the horse, a divergent pattern of gonadotrophins is observed at different stages of the reproductive cycle in response to a single secretagogue (gonadotrophin-releasing hormone), and dramatic changes in fertility take place throughout the year in response to photoperiod. This species thus provides a useful model to investigate the regulation of fertility directly at the level of the hypophysis. A series of studies were undertaken to examine the cytological arrangements and heterogeneity of gon...
Insulin-like growth factor-I enhances cell-based repair of articular cartilage.
The Journal of bone and joint surgery. British volume    April 2, 2002   Volume 84, Issue 2 276-288 doi: 10.1302/0301-620x.84b2.11167
Fortier LA, Mohammed HO, Lust G, Nixon AJ.Composites of chondrocytes and polymerised fibrin were supplemented with insulin-like growth factor-I (IGF-I) during the arthroscopic repair of full-thickness cartilage defects in a model of extensive loss of cartilage in horses. Repairs facilitated with IGF-I and chondrocyte-fibrin composites, or control defects treated with chondrocyte-fibrin composites alone, were compared before death by the clinical appearance and repeated analysis of synovial fluid, and at termination eight months after surgery by tissue morphology, collagen typing, and biochemical assays. The structure of cartilage was ...
Prostaglandin E2 and reactive oxygen metabolite damage in the cecum in a pony model of acute colitis.
Canadian journal of veterinary research = Revue canadienne de recherche veterinaire    February 23, 2002   Volume 66, Issue 1 50-54 
McConnico RS, Argenzio RA, Roberts MC.The objective of this project was to determine early tissue biochemical events associated with increased colonic secretion during the acute stage of castor-oil-induced colitis by measuring cecal mucosal and submucosal malondialdehyde (MDA) and prostaglandin E2 (PGE2), levels in ponies. Intestinal tissue (inflamed or healthy) samples were obtained from 4 age- and sex-matched Shetland ponies. Biochemical methods were used to determine MDA and PGE2 levels in intestinal tissue samples from inflamed and healthy equine intestine. Inflamed tissue MDA and PGE2 levels increased with time after castor o...
Thyroid-stimulating hormone in adult euthyroid and hypothyroid horses.
Journal of veterinary internal medicine    February 2, 2002   Volume 16, Issue 1 109-115 doi: 10.1892/0891-6640(2002)016<0109:tshiae>2.3.co;2
Breuhaus BA.The purpose of this study was to validate a thyroid-stimulating hormone (TSH) assay in a model of equine hypothyroidism. Thyrotropin-releasing hormone (TRH) stimulation tests were performed in 12 healthy adult mares and geldings, aged 4 to greater than 20 years. before and during administration of the antithyroid drug propylthiouracil (PTU) for 6 weeks. Serum concentrations of equine TSH, total and free thyroxine (T4), and total and free triiodothyronine (T3) were measured. Before PTU administration, mean +/- standard deviation baseline concentrations of TSH were 0.40 +/- 0.29 ng/mL. TSH incre...
Successful production of offspring after superovulation and in vitro culture of embryos from domestic ferrets (Mustela putorius furos).
Reproduction (Cambridge, England)    January 31, 2002   Volume 122, Issue 4 611-618 
Li ZY, Jiang QS, Zhang YL, Liu XM, Engelhardt JF.In an effort to expand the use of ferrets as models for genetic disease, several experimental parameters that are required for successful genetic manipulation in this species were investigated. Optimum superovulation (19.3 +/- 0.6 oocytes and embryos per female) was achieved after injections of 100 iu equine chorionic gonadotrophin (eCG) and 150 iu human chorionic gonadotrophin (hCG). The ovulation rate achieved by the treatment was more than double that induced by mating. Mating with a male immediately after hCG treatment did not significantly alter the number of oocytes ovulated or the numbe...
Finite element analysis (FEA) as a model to predict effects of farriery on the equine hoof.
Equine veterinary journal. Supplement    November 28, 2001   Issue 33 58-62 doi: 10.1111/j.2042-3306.2001.tb05360.x
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...
In vivo imaging of physiological angiogenesis from immature to preovulatory ovarian follicles.
The American journal of pathology    November 7, 2001   Volume 159, Issue 5 1661-1670 doi: 10.1016/S0002-9440(10)63013-1
Vollmar B, Laschke MW, Rohan R, Koenig J, Menger MD.To develop a model for the study of physiological angiogenesis, we transplanted ovarian follicles onto striated muscle tissue and analyzed the process of microvascularization in vivo using repeated fluorescence microscopy. Follicles were mechanically isolated from unstimulated as well as pregnant mare's serum gonadotropin (PMSG)- or PMSG/luteinizing hormone (LH)-stimulated Syrian golden hamster ovaries and were transplanted as free grafts into dorsal skinfold chambers of untreated or synchronized hamsters. Follicles lacking thecal cell layers did not vascularize regardless whether harvested fr...
Enhanced survival of lung granulocytes in an animal model of asthma: evidence for a role of GM-CSF activated STAT5 signalling pathway.
Thorax    August 22, 2001   Volume 56, Issue 9 696-702 doi: 10.1136/thorax.56.9.696
Turlej RK, Fiévez L, Sandersen CF, Dogné S, Kirschvink N, Lekeux P, Bureau F.As granulocyte/macrophage colony stimulating factor (GM-CSF) mediated delay of granulocyte apoptosis contributes to the accumulation of inflammatory cells at the site of inflammation in many diseases, we sought to determine whether asthma is also associated with a GM-CSF dependent increase in lung granulocyte survival. Moreover, because GM-CSF mediates its effects through activation of signal transducer and activator of transcription 5 (STAT5), we also investigated the potential role of STAT5 in allergic inflammation. Methods: Blood granulocytes were recovered from six healthy and six heaves a...
Tumor regression induced by intratumoral injection of DNA coding for human interleukin 12 into melanoma metastases in gray horses.
Journal of molecular medicine (Berlin, Germany)    July 4, 2001   Volume 78, Issue 12 692-702 doi: 10.1007/s001090000165
Heinzerling LM, Feige K, Rieder S, Akens MK, Dummer R, Stranzinger G, Moelling K.Preclinical studies investigating new therapeutic principles against melanoma are presently being carried out in mouse models; however, these are not optimal. Here we describe a novel animal model using gray horses. These animals spontaneously develop metastatic melanoma that resembles human disease and is thus highly relevant for preclinical studies testing new immunotherapy protocols. We found that injection of plasmid DNA coding for the human cytokine interleukin 12 into established metastases induced significant regression in all 12 treated lesions in a total of 7 horses. Complete disappea...
Chemical, physical, and environmental properties of pelleted newspaper compared to wheat straw and wood shavings as bedding for horses.
Journal of animal science    June 27, 2001   Volume 79, Issue 6 1359-1369 doi: 10.2527/2001.7961359x
Ward PL, Wohlt JE, Katz SE.Two experiments were conducted comparing pelleted recycled newspaper (PN) to wheat straw (S) and kiln-dried pine wood shavings (WS) as an animal bedding material. Adult horses housed 20 to 21 h/d in boxstalls served as the animal model for comparisons. In Exp. 1 eight boxstalls, each housing one horse, were each bedded with two types of PN (0.32 and 0.64 x 2.54 cm), S, and WS over four 5-d periods (replicated 4 x 4 Latin square). Initial amounts of bedding materials surpassed most commercial conditions, but stalls were cleaned daily of feces only and additional clean bedding was added as neede...
The surgical technique and the age of the horse both influence the outcome of mosaicplasty in a cadaver equine stifle model.
Acta veterinaria Hungarica    June 14, 2001   Volume 49, Issue 1 111-116 doi: 10.1556/004.49.2001.1.13
Bodó G, Kaposi AD, Hangody L, Tóth J, Bakos Z, Lukács Z, Péntek G.Six pieces of grafts, 6.5 mm in diameter, 20 mm in length, were taken from each of 170 cadaver hindlimbs, using the cranial surface of the medial femoral trochlea for harvesting. The age of the horses varied between 4 months and 23 years. 30 limbs under the age of 12 years were selected for transplantation. Three of six grafts were transplanted into the medial femoral condyle using different combinations of tunnel depth and dilation. With ageing, a significant decline in transplantability was detected. In general, mosaicplasty cannot be recommended in horses above 11 years. Based on a previous...
Lipid phase separation correlates with activation in platelets during chilling.
Molecular membrane biology    April 17, 2001   Volume 17, Issue 4 209-218 doi: 10.1080/09687680010013966
Tsvetkova NM, Walker NJ, Crowe JH, Field CL, Shi Y, Tablin F.When human platelets are chilled below 22 degrees C, they spontaneously activate, a phenomenon that severely limits their storage life. It has previously been proposed that there is a correlation between cold-induced platelet activation and passage of the membranes through a liquid-crystalline to gel phase transition. Because animal models are essential for developing methods for cold storage of platelets, it is necessary to investigate such a correlation in animal platelets. In this work, horse platelets were used as a model, and it was found that cold-induced morphological activation is rela...
In vitro model of equine muscle regeneration.
Equine veterinary journal    October 19, 2000   Volume 32, Issue 5 401-405 doi: 10.2746/042516400777591020
Byrne KM, Vierck J, Dodson MV.Equine satellite cells are responsible for muscle healing and regeneration in the mature horse. We describe the in vitro cell culture conditions required for clonal populations of equine satellite cells to undergo both proliferation and differentiation. Our hypothesis is that these in vitro conditions model regeneration of muscle and can be used to evaluate potential therapeutics. In this study, 2 areas of satellite cell response were tested: proliferation of clones induced by growth factors, and fusion induced by culture conditions. Equine satellite cell clones showed differences in their res...
Animal models of asthma: potential usefulness for studying health effects of inhaled particles.
Inhalation toxicology    September 16, 2000   Volume 12, Issue 9 829-862 doi: 10.1080/08958370050123207
Bice DE, Seagrave J, Green FH.Asthma is now recognized to be a chronic inflammatory disease that affects the whole lung. Incidence appears to be increasing despite improved treatment regimens. There is substantial epidemiological evidence suggesting a relationship between the incidence and severity of asthma (e.g., hospitalizations) and exposure to increased levels of air pollution, especially fine and ultrafine particulate material, in susceptible individuals. There have been a few studies in animal models that support this concept, but additional animal studies to test this hypothesis are needed. However, such studies mu...
Inoculation of Sarcocystis neurona merozoites into the central nervous system of horses.
Veterinary parasitology    August 18, 2000   Volume 92, Issue 2 157-163 doi: 10.1016/s0304-4017(00)00281-8
Lindsay DS, Dykstra CC, Williams A, Spencer JA, Lenz SD, Palma K, Dubey JP, Blagburn BL.Equine protozoal myeloencephalitis (EPM) is a neurologic syndrome in horses from the Americas and is usually caused by infection with the apicomplexan parasite, Sarcocystis neurona. A horse model of EPM is needed to test the efficacy of chemotherapeutic agents and potential vaccines. Five horses that were negative for antibodies to S. neurona in their serum and cerebrospinal fluid (CSF) were injected in the subarachnoid space with living merozoites of the SN2 isolate of S. neurona. None of the horses developed clinical disease or died over a 132-day observation period. All five horses develope...
Alterations in cartilage type-II procollagen and aggrecan contents in synovial fluid in equine osteochondrosis.
Journal of orthopaedic research : official publication of the Orthopaedic Research Society    August 11, 2000   Volume 18, Issue 3 399-405 doi: 10.1002/jor.1100180311
Laverty S, Ionescu M, Marcoux M, Bouré L, Doizé B, Poole AR.The etiology and pathophysiology of osteochondrosis remain poorly understood because it is difficult to obtain material from lesions in the early stage of this disease and because there is no satisfactory experimental animal model. We wished to determine whether there are changes in articular cartilage turnover in equine osteochondrosis, which closely resembles the human disease, by assaying cartilage matrix molecules in synovial fluids. We used immunoassays that measure a keratan sulfate epitope and the epitope 846 on the cartilage proteoglycan aggrecan and the C-propeptide of cartilage type-...
Comparative aspects of equine embryonic development.
Animal reproduction science    June 14, 2000   Volume 60-61 691-702 doi: 10.1016/s0378-4320(00)00075-0
Betteridge KJ.The developmental changes in the equine conceptus, its maternal environment and their interaction during the first 4 weeks following fertilization are reviewed. Attention is drawn to species-specific events to show why the horse is such a valuable model in which to study early pregnancy.
Correlation between nuclear factor-kappaB activity in bronchial brushing samples and lung dysfunction in an animal model of asthma.
American journal of respiratory and critical care medicine    April 14, 2000   Volume 161, Issue 4 Pt 1 1314-1321 doi: 10.1164/ajrccm.161.4.9907010
Bureau F, Bonizzi G, Kirschvink N, Delhalle S, Desmecht D, Merville MP, Bours V, Lekeux P.Asthma is a chronic inflammatory disease of the airways, in which many inflammatory genes are overexpressed. Transcription factor, nuclear factor-kappaB (NF-kappaB), which is thought to control the transcriptional initiation of inflammatory genes, has been poorly investigated in asthma. In the present report, bronchial cells (BCs), recovered by bronchial brushing in healthy and heaves-affected horses (i.e., an animal model of asthma), were assessed for NF-kappaB activity. Small amounts of active NF-kappaB were present in BCs of healthy horses, whereas high levels of NF-kappaB activity was foun...
Equine bullous pemphigoid IgG autoantibodies target linear epitopes in the NC16A ectodomain of collagen XVII (BP180, BPAG2).
Veterinary immunology and immunopathology    March 4, 2000   Volume 73, Issue 1 45-52 doi: 10.1016/s0165-2427(99)00151-8
Olivry T, Borrillo AK, Xu L, Dunston SM, Slovis NM, Affolter VK, Demanuelle TC, Chan LS.Bullous pemphigoid (BP) is an autoimmune subepithelial blistering dermatosis of humans, dogs, cats and pigs. It is characterized by skin-fixed and circulating IgG autoantibodies that target one or both BP antigens. An immunological homologue of BP in humans was diagnosed in two horses with cutaneous and mucosal ulcerations as well as microscopic subepithelial vesiculation. Immunological investigations revealed similar findings for both the horses. Direct immunofluorescence demonstrated the presence of IgG deposited linearly at the dermoepidermal junction in mucosal and skin biopsy specimens. I...
Functional characterization of equine dendritic cells propagated ex vivo using recombinant human GM-CSF and recombinant equine IL-4.
Veterinary immunology and immunopathology    December 10, 1999   Volume 71, Issue 3-4 197-214 doi: 10.1016/s0165-2427(99)00094-x
Hammond SA, Horohov D, Montelaro RC.Naive T cells can be activated both in vivo and in vitro by specialized antigen presenting cells, dendritic cells (DC), with potent antigen-specific, immunostimulatory activity. Indeed, DC can provide an extremely powerful and important immunological tool by which to potentiate the immune response for specific recognition of foreign antigens. Until recently, the direct isolation of DC from PBMC required laborious procedures with extremely poor yields (<0.1%). Methods have been developed for the human, lower primate, and murine model systems to propagate large numbers of DC from PBMC or bone...
Metabolic functions of L-carnitine and its effects as feed additive in horses. A review.
Archiv fur Tierernahrung    November 5, 1999   Volume 52, Issue 2 115-138 doi: 10.1080/17450399909386157
Zeyner A, Harmeyer J.L-carnitine, a betaine derivative of beta-hydroxybutyrate, is found in virtually all cells of higher animals and also in some microorganisms and plants. In animals it is synthesized almost exclusively in the liver. Two essential amino acids, i.e., lysine and methionine serve as primary substrates for its biosynthesis. Also required for its synthesis are sufficient amounts of vitamin B6, nicotinic acids, vitamin C and folate. The first discovered ergogenic function of L-carnitine is the transfer of activated long-chain fatty acids across the inner mitochondrial membrane into the mitochondrial m...
Potential of DNA-mediated vaccination for equine herpesvirus 1.
Veterinary microbiology    September 29, 1999   Volume 68, Issue 1-2 35-48 doi: 10.1016/s0378-1135(99)00059-0
Ruitenberg KM, Walker C, Wellington JE, Love DN, Whalley JM.The potential of DNA-mediated immunisation to protect against equine herpesvirus 1 (EHV-1) disease was assessed in a murine model of EHV-1 respiratory infection. Intramuscular injection with DNA encoding the EHV-1 envelope glycoprotein D (gD) in a mammalian expression vector induced a specific antibody response detectable by two weeks and maintained through 23 weeks post injection. Immune responses were proportional to the dose of DNA and a second injection markedly enhanced the antibody response. EHV-1 gD DNA-injected mice developed neutralising antibodies, and a predominance of IgG2a antibod...
Dual regulation of promoter II- and promoter 1f-derived cytochrome P450 aromatase transcripts in equine granulosa cells during human chorionic gonadotropin-induced ovulation: a novel model for the study of aromatase promoter switching.
Endocrinology    August 28, 1999   Volume 140, Issue 9 4133-4141 doi: 10.1210/endo.140.9.6951
Boerboom D, Kerban A, Sirois J.Estradiol biosynthesis is a key biochemical trait of developing follicles. To study its regulation in equine follicles, the objectives of this study were to clone and determine the structure of equine cytochrome P450 aromatase (P450AROM), and characterize the regulation of P450AROM and P450 17alpha-hydroxylase/C17-20 lyase (P45017alpha) messenger RNAs (mRNAs) in vivo in equine preovulatory follicles isolated during hCG-induced ovulation. Two distinct P450AROM complementary DNAs (cDNAs) were isolated from an equine preovulatory follicle cDNA library. One clone was 2682 bp in length and included...
Myeloperoxidase activity of the large intestine in an equine model of acute colitis.
American journal of veterinary research    July 17, 1999   Volume 60, Issue 7 807-813 
McConnico RS, Weinstock D, Poston ME, Roberts MC.To determine whether quantification of myeloperoxidase (MPO) activity could be a useful laboratory technique to detect granulocyte infiltration in equine intestinal tissues. Methods: Intestinal tissue (inflamed or healthy) collected from 16 age- and sex-matched Shetland Ponies. Methods: Intestinal tissue MPO activity was determined, and histologic assessment of adjacent specimens from healthy and inflamed intestine was done. Results: Intestinal tissue MPO activity and histopathologic score increased with time after castor oil challenge and peaked at 16 hours in an equine diarrhea model in whic...
A pharmacodynamic and pharmacokinetic study with vedaprofen in an equine model of acute nonimmune inflammation.
Journal of veterinary pharmacology and therapeutics    June 18, 1999   Volume 22, Issue 2 96-106 doi: 10.1046/j.1365-2885.1999.00173.x
Lees P, May SA, Hoeijmakers M, Coert A, Rens PV.The pharmacodynamics and enantioselective pharmacokinetics of vedaprofen were studied in six ponies in a two period cross-over study, in which a mild acute inflammatory reaction was induced by carrageenan soaked sponges implanted subcutaneously in the neck. Vedaprofen, administered intravenously at a dosage of 1 mg/kg, produced significant and prolonged inhibition of ex vivo serum thromboxane B2 (TXB2) synthesis and short-lived inhibition of exudate prostaglandin E2 (PGE2) and TXB2 synthesis. Vedaprofen also partially inhibited oedematous swelling and leucocyte infiltration into exudate. Vedap...
Infection with equine herpesvirus 1 (EHV-1) strain HVS25A in pregnant mice.
Journal of comparative pathology    March 31, 1999   Volume 120, Issue 1 15-27 doi: 10.1053/jcpa.1998.0251
Walker C, Perotti VM, Love DN, Whalley JM.The abortigenic effects of equine herpesvirus 1 (EHV-1) strain HVS25A, given intranasally, were assessed in pregnant BALB/c, C57BL/6J and Quakenbush mice at day 16 of pregnancy. All EHV-1-infected BALB/c mice showed clinical signs typical of EHV-1-induced disease, together with evidence of abortion. However, although there were fetal and neonatal deaths in some C57BL/6J and Quakenbush litters, the respiratory and systemic effects of EHV-1 infection in the dams were inconsistent. BALB/c dams were then inoculated at day 15 of pregnancy with either EHV-1 or rabbit kidney (RK) cell lysate (control...
Arterially perfused eye model of uveitis.
Australian veterinary journal    March 17, 1999   Volume 77, Issue 2 100-104 doi: 10.1111/j.1751-0813.1999.tb11677.x
Shiels IA, Sanderson SD, Taylor SM.To develop an in vitro model of uveitis based on an ex situ perfused eye to evaluate the anti-inflammatory activity of new pharmacological products. Methods: Eyes were removed from more than 60 dogs and 9 horses immediately after euthanasia and perfused with nutrient medium through the lateral long ciliary artery. Perfused eyes produced aqueous humour, and perfusion pressure was adjusted to obtain an intraocular pressure in the physiological range. When the eyes were treated with histamine, a complement C5a analogue peptide and hydrogen peroxide, typical signs of uveitis were produced. These i...
Scrotal heat stress induces altered sperm chromatin structure associated with a decrease in protamine disulfide bonding in the stallion.
Biology of reproduction    February 20, 1999   Volume 60, Issue 3 615-620 doi: 10.1095/biolreprod60.3.615
Love CC, Kenney RM.A variety of testicular insults can induce changes in the structure of spermatozoal chromatin, resulting in spermatozoal DNA that is more susceptible to acid-induced denaturation. The degree of change in the DNA can be measured using the sperm chromatin structure assay (SCSA). The SCSA measures the relative amounts of single- and double-stranded DNA after staining with the metachromatic dye, acridine orange. Here we used a stallion model (n = 4) to study the effects of scrotal heat stress on spermatozoal DNA. This model was created by insulating stallion testes for 48 h and collecting sperm da...
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