Equine health encompasses the study and management of diseases, disorders, and overall well-being of horses. It involves understanding various physiological systems, preventive care, and treatment strategies to maintain optimal health in equine populations. Common areas of focus include nutrition, infectious diseases, orthopedic conditions, and reproductive health. Research in equine health aims to advance knowledge on diagnostic methods, therapeutic interventions, and management practices that improve horse welfare and performance. This page collects peer-reviewed research studies and scholarly articles that explore the diverse aspects of equine health, offering insights into current findings and advancements in the field.
Reardon RJ, Boden LA, Mellor DJ, Love S, Newton RJ, Stirk AJ, Parkin TD.The aim of this study was to evaluate risk factors associated with developing epistaxis in jump racing in Great Britain (GB). A retrospective analysis of records from horses running in all hurdle and steeplechase races in GB between 2001 and 2009 identified diagnoses of epistaxis whilst still at the racecourse. Data were used from 603 starts resulting in epistaxis (event) and 169,065 starts resulting in no epistaxis (non-event) in hurdle racing, and from 550 event starts and 102,344 non-event starts in steeplechase racing. Two multivariable logistic regression models to evaluate risk factors a...
Radtke CL, Nino-Fong R, Rodriguez-Lecompte JC, Esparza Gonzalez BP, Stryhn H, McD￮ LA.The objectives of this study were to use non-equilibrium gravitational field-flow fractionation (GrFFF), an immunotag-less method of sorting mesenchymal stem cells (MSCs), to sort equine muscle tissue-derived mesenchymal stem cells (MMSCs) and bone marrow-derived mesenchymal stem cells (BMSC) into subpopulations and to carry out assays in order to compare their osteogenic capabilities. Cells from 1 young adult horse were isolated from left semitendinosus muscle tissue and from bone marrow aspirates of the fourth and fifth sternebrae. Aliquots of 800 × 10(3) MSCs from each tissue source were s...
Leclere M, Lavoie-Lamoureux A, Lavoie JP.Systemic inflammation is observed in horses with heaves and could also be present in horses with a lesser degree of pulmonary inflammation. Objective: It was hypothesized that racehorses with inflammatory airway disease (IAD) have increased concentration of circulating acute phase proteins. The objective of this study was to compare serum acute phase proteins of racehorses with and without lower airway inflammation. Methods: Serum from 21 client-owned Standardbred racehorses with exercise intolerance and lower airway inflammation and serum from 10 client-owned Standardbred racehorses with exer...
Mullen KR, Furness MC, Johnson AL, Norman TE, Hart KA, Burton AJ, Bicahlo RC, Ainsworth DM, Thompson MS, Scrivani PV.The study was prompted by a perceived high prevalence of myelographic complications varying in severity and type, and attributed to the contrast material or the procedure. Objective: 1. Any adverse reaction (AAR) is associated with a change in CSF volume induced either by removal of CSF or addition of contrast material. 2. AAR occurs more frequently in horses with higher premyelography neurologic grade. 3. Nonspecific hyperthermia is attenuated by anti-inflammatory and osmotic agents. Methods: Horses (n = 278) that underwent myelography between 2000 and 2012 at 5 institutions: A (87), B (68), ...
Larson KR, Heil GL, Chambers TM, Capuano A, White SK, Gray GC.Equine influenza virus (EIV) is considered enzootic in North America and experimental studies have documented human EIV infections. Methods: This cross-sectional study examined 94 horse-exposed and 34 non-exposed controls for serological evidence of EIV infection. Sera were evaluated for antibodies against three EIV and two human H3N2 viruses using microneutralization (MN), neuraminidase inhibition (NI), enzyme-linked lectin (ELLA), and hemagglutination inhibition (HI) serological assays. Risk factor analyses were conducted using logistic regression and proportional odds modeling. Results: The...
Birhanu H, Fikru R, Said M, Kidane W, Gebrehiwot T, Hagos A, Alemu T, Dawit T, Berkvens D, Goddeeris BM, Büscher P.African animal trypanosomosis, transmitted cyclically by tsetse flies or mechanically by other biting flies, causes serious inflictions to livestock health. This study investigates the extent of non-tsetse transmitted animal trypanosomosis (NTTAT) by Trypanosoma (T.) evansi and T. vivax in domestic animals in the tsetse-free regions of Northern Ethiopia, Afar and Tigray. Methods: A cross sectional study was conducted on 754 dromedary camels, 493 cattle, 264 goats, 181 sheep, 84 donkeys, 25 horses and 10 mules. The microhaematocrit centrifugation technique was used as parasitological test. Plas...
Hill AE, Blea JA, Arthur RM, McIlwraith CW.Private-practice racetrack veterinarians in southern California recorded non-fatal injuries meeting defined criteria in Thoroughbreds for 1 year. Injury incidence was 2.29 injury events per 100 horse-months, which was lower than other studies where trainer reported injury data were collected. Of 477 injuries recorded, 344 (72.1%) were acute and 133 (27.9%) were chronic. Fractures were common (47.6% of injuries), with stress fractures accounting for 14% of injuries. Superficial digital flexor tendonitis and suspensory ligament desmitis accounted for 15.3 and 11.5% of injuries, respectively. Agr...
Briganti A, Portela DA, Grasso S, Sgorbini M, Tayari H, Bassini JR, Vitale V, Romano MS, Crovace A, Breghi G, Staffieri F.The aim of this study was to evaluate the correlation of commonly used oxygenation indices with venous admixture (Qs/Qt) in anaesthetised horses under different infusion rates of dobutamine. Six female horses were anaesthetised with acepromazine, xylazine, diazepam, ketamine, and isoflurane, and then intubated and mechanically ventilated with 100% O2. A Swan-Ganz catheter was introduced into the left jugular vein and its tip advanced into the pulmonary artery. Horses received different standardised rates of dobutamine. For each horse, eight samples of arterial and mixed venous blood were simul...
Payne E, Boot M, Starling M, Henshall C, McLean A, Bennett P, McGreevy P.This review collates peer-reviewed evidence for desirable attributes for those who work with dogs and horses. It is written with a particular focus on the veterinary profession. Although veterinarians and veterinary nurses (VNs) occupy variable roles when interacting with their patients, several behavioural attributes emerge as helpful across the range of such roles. In light of recent research on the value of considering animals' arousal and affective state as predictors of behaviour and welfare, best practice in human-horse and human-dog-interactions is outlined. The attributes of affiliatio...
Teubner A, Müller K, Bartmann CP, Sieme H, Klug E, Zingrebe B, Schoon HA.The aim of this study was to determine the effect of the anabolic steroid testosterone on the testicular vascularization, angiogenesis and expression of angiogenic factors, and their receptors in testes of peripubertal stallions. Seven peripubertal stallions were treated with Durateston and castrated either 4 (treatment group 1 [TG1]) or 12 weeks (TG2) after the last injection. The castration of seven untreated control stallions (control group [CG]) took place within the same time. In the testicular specimens, volume density (VD), numerical density (ND), and area of vessels were determined mor...
Kinoshita Y, Niwa H, Katayama Y.Microbial substitution occasionally occurs following the administration of antimicrobials to horses that have pneumonia or pleuropneumonia. Four specific loop-mediated isothermal amplification (LAMP) assays were developed to detect some equine respiratory pathogens, namely strains of the Bacteroides-Prevotella group, Klebsiella pneumoniae, Stenotrophomonas maltophilia, and Staphylococcus aureus. These four LAMP assays and two previously published LAMP assays targeting Escherichia coli or Pseudomonas aeruginosa were used on clinical respiratory specimens and a high accordance found between the ...
Roberts VL, Patel NK, Tremaine WH.There are no consistently safe and effective methods for the treatment of trigeminal-mediated headshaking in horses. In affected horses, the trigeminal nerve is sensitised, appearing to result in neuropathic pain. Percutaneous electrical nerve stimulation (PENS) therapy is a minimally invasive neuromodulatory treatment used in people to manage neuropathic pain. Objective: To determine whether PENS therapy is safe, tolerated and effective for the management of trigeminal-mediated headshaking in horses. Methods: Descriptive case series. Methods: Seven horses diagnosed with trigeminal-mediated he...
Mehdizadeh Gohari I, Parreira VR, Nowell VJ, Nicholson VM, Oliphant K, Prescott JF.A role for type A Clostridium perfringens in acute hemorrhagic and necrotizing gastroenteritis in dogs and in necrotizing enterocolitis of neonatal foals has long been suspected but incompletely characterized. The supernatants of an isolate made from a dog and from a foal that died from these diseases were both found to be highly cytotoxic for an equine ovarian (EO) cell line. Partial genome sequencing of the canine isolate revealed three novel putative toxin genes encoding proteins related to the pore-forming Leukocidin/Hemolysin Superfamily; these were designated netE, netF, and netG. netE a...
Janssen IJ, Krücken J, Demeler J, von Samson-Himmelstjerna G.P-glycoproteins (Pgps) are suspected to mediate drug extrusion in nematodes contributing to macrocyclic lactone resistance. This association was recently shown for Parascaris Pgp-11. Ivermectin resistance was correlated with the presence of three pgp-11 single nucleotide polymorphisms and/or increased pgp-11 mRNA levels. In the present study, the ability of Pgp-11 to modulate ivermectin susceptibility was investigated by its expression in a pgp-11-deficient Caenorhabditis elegans strain. Expression of Parascaris pgp-11 in two transgenic lines significantly decreased ivermectin susceptibility i...
Gajos K, Kozdrowski R, Nowak M, Siemieniuch MJ.Mares that fail to become pregnant after repeated breeding, without showing typical signs of clinical endometritis, should be suspected of subclinical endometritis (SE). Contact with infectious agents results in altered synthesis and secretion of inflammatory mediators, including cytokines and arachidonic acid metabolites, and disturbs endometrial functional balance. To address the hypothesis that SE affects the immune endocrine status of the equine endometrium, spontaneous secretion of prostaglandin E(2) (PGE(2)), prostaglandin F(2α) (PGF(2α)), 6-keto-PGF(1α )(a metabolite of prostacyclin ...
Choi YH, Ross P, Velez IC, Macías-García B, Riera FL, Hinrichs K.Equine embryos develop in vitro in the presence of high glucose concentrations, but little is known about their requirements for development. We evaluated the effect of glucose concentrations in medium on blastocyst development after ICSI. In experiment 1, there were no significant differences in rates of blastocyst formation among embryos cultured in our standard medium (DMEM/F-12), which contained >16 mM glucose, and those cultured in a minimal-glucose embryo culture medium (<1 mM; Global medium, GB), with either 0 added glucose for the first 5 days, then 20 mM (0-20) or 20 mM for th...
Hillmann A, Ahrberg AB, Brehm W, Heller S, Josten C, Paebst F, Burk J.Multipotent mesenchymal stromal cells (MSCs) have gained tremendous attention as potential therapeutic agents for the treatment of orthopedic diseases. Promising results have been obtained after application of MSCs for treatment of tendon and joint disease in the equine model, making it appear favorable to use these results as a basis for the translational process of the therapy. However, while the horse is considered a highly suitable model for orthopedic diseases, knowledge is lacking regarding the level of analogy of equine MSCs and their human counterparts. Therefore, the aim of this study...
Kravtsov AL.Compare the content of bactericidal granules (BG) in blood phagocytes of animals, that differ by species sensitivity to plague infection, under the conditions of measuring, that ensure automatic differentiating by this parameter of monocytes and granulocytes of human blood. Methods: Human whole blood leukocytes were studied, as well as from 7 animal species: mice, guinea pigs, golden hamsters, white rats, rabbits, dogs and horses. Acridine orange (AO) was used for supra-vital staining in primary (bactericidal) granule cells. Relative BG content was measured in separate cells in conventional un...
McGill SL, Gutierrez-Nibeyro SD, Schaeffer DJ, Hartman SK, O'Brien RT, Joslyn SK.Abnormalities of the deep digital flexor tendon, navicular bone, and collateral sesamoidean ligament can be difficult to visualize using magnetic resonance imaging (MRI) if bursal fluid is absent. The use of saline podotrochlear bursography improves podotrochlear apparatus evaluation, however, the technique has disadvantages. The objective of this prospective feasibility study was to describe saline arthrography of the distal interphalangeal joint as an alternative technique for improving MRI visualization of the deep digital flexor tendon, navicular bone, collateral sesamoidean ligament, and ...
Gill Harris reports from this year's National Equine Forum, where one of the main themes was the horse industry and government. The forum, held in London on March 5, was attended by more than 200 people with a connection to the equestrian industry. Lord de Mauley, parliamentary undersecretary of state for natural environment and science at Defra, set the course of the proceedings.
Lorello O, Foster DL, Levine DG, Boyle A, Engiles J, Orsini JA.Equine odontoclastic tooth resorption and hypercementosis is an infrequent and underdiagnosed form of severe dental disease in horses that can affect quality of life. The study was performed to compare the clinical, radiographic, histological and prognostic findings specific to equine odontoclastic tooth resorption and hypercementosis in horses. Removal of affected teeth is currently the best treatment. Objective: The goals are to report salient clinical and histological features of the disease and its management in a case series describing an under-reported syndrome in horses and the long-ter...
Woodward EM, Troedsson MH.Transient post breeding endometritis is a normal physiological reaction in the mare, as it is believed that an inflammatory response is necessary for the effective removal of contaminating bacteria and excess spermatozoa introduced into the uterus. While most mares can clear endometritis within a reasonable amount of time, persistent endometritis caused by either bacteria or spermatozoa can threaten the success of a pregnancy. A subpopulation of mares is susceptible to persistent endometritis, and these mares are a concern in equine reproductive medicine. Research has identified several factor...
Menendez MI, Phelps MA, Bertone AL.To the date, no reports exist of the pharmacokinetics (PK) of betamethasone (BTM) sodium phosphate and betamethasone acetate administered intra-articular (IA) into multiple joints in exercising horses. The purpose of the study was to determine the PK of BTM and HYD concentrations in plasma and urine after IA administration of a total of 30 mg BTM. Eight 4 years old Thoroughbred mares were exercised on a treadmill and BTM was administered IA. Plasma and urine BTM and HYD were determined via high performance liquid chromatography spectrometry for 6 weeks. Concentration-time profiles of BTM and H...
Jacobson E, Dart AJ, Mondori T, Horadogoda N, Jeffcott LB, Little CB, Smith MM.It is not known how extensively a localised flexor tendon injury affects the entire tendon. This study examined the extent of and relationship between histopathologic and gene expression changes in equine superficial digital flexor tendon after a surgical injury. One forelimb tendon was hemi-transected in six horses, and in three other horses, one tendon underwent a sham operation. After euthanasia at six weeks, transected and control (sham and non-operated contralateral) tendons were regionally sampled (medial and lateral halves each divided into six 3 cm regions) for histologic (scoring and ...
Gonçalves R, Malalana F, McConnell JF, Maddox T.For accurate interpretation of magnetic resonance (MR) images of the equine brain, knowledge of the normal cross-sectional anatomy of the brain and associated structures (such as the cranial nerves) is essential. The purpose of this prospective cadaver study was to describe and compare MRI and computed tomography (CT) anatomy of cranial nerves' origins and associated skull foramina in a sample of five horses. All horses were presented for euthanasia for reasons unrelated to the head. Heads were collected posteuthanasia and T2-weighted MR images were obtained in the transverse, sagittal, and do...
Wobeser BK.During a widespread anthrax outbreak in Canada, miniature horses were vaccinated using a live spore anthrax vaccine. Several of these horses died from an apparent immune-mediated vasculitis temporally associated with this vaccination. During the course of the outbreak, other miniature horses from different regions with a similar vaccination history, clinical signs, and necropsy findings were found. Vaccin contre l’anthrax associé à la mort de chevaux miniatures. Durant une vaste éclosion d’anthrax au Canada, des chevaux miniatures ont été vaccinés en utilisant un vaccin à base de sp...
Lutter JD, Cary JA, Stephens RR, Potts LB.Determine the relative stiffness of 3 bandage/splint constructs intended for emergency fracture stabilization. Methods: Experimental model. A single plane free end deflection model was developed to simulate the forces placed on a bandage/splint construct during stabilization of a complete mid-metacarpal bone fracture. The total deflection of the model in one plane was measured following application of 3 different bandage/splint combinations including a classic, 3 layered Robert Jones Bandage (RJB) with a splint placed on the outside of the bandage (RJB-3), an RJB with splint placed after the f...
Post EM, Singer ER, Clegg PD.To establish an injection site for the gastrocnemius calcaneal bursa (GCB), to identify communication patterns between the calcaneal bursae, to estimate the proximal and distal extents of the intertendinous calcaneal bursa (ICB) and to identify variations from previous anatomic descriptions. Methods: Descriptive anatomic study. Methods: Cadaveric equine hindlimbs (n=18) from 9 adult horses. Methods: Communication between the ICB and GCB was determined in 18 cadaveric hindlimbs by injection of a latex mixture, followed by examination of sequential sagittal sections and documentation of the dist...
Benamou AE, Art T, Marlin DJ, Roberts CA, Lekeux P.Recurrent airway obstruction (RAO) is an asthma-like condition of the horse that represents a major cause of morbidity and loss of performance. The exact pathogenesis of asthma in man is unclear but the role of endothelin (ET) is currently under investigation, thus sparking interest in the bronchoconstrictive and vasoconstrictive properties of endothelin in the equine-specific disease entity. In this study, we investigated the levels of ET-1 in systemic blood, as well as in bronchoalveolar lavage (BAL) from horses with RAO. We also studied how these values might correlate with those of lung fu...
O'Conner MS, Steiner JM, Roussel AJ, Williams DA, Meddings JB, Pipers F, Cohen ND.To evaluate the use of sucrose permeability testing to detect ulcers in the gastric squamous mucosa of horses. Methods: 13 adult horses ranging from 5 to 19 years of age. Methods: Following induction of gastric ulcers by intermittent feed deprivation, horses underwent sucrose permeability testing (administration of sucrose by nasogastric intubation followed by collection of urine at 2 and 4 hours after intubation) and gastric endoscopy. Squamous ulcers were assigned a severity score (range, 0 to 3) by use of an established scoring system. Horses were subsequently administered omeprazole for 21...
Rivera Del Alamo MM, Katila T, Palviainen M, Reilas T.Intrauterine devices block luteolysis in cyclic mares, but the underlying mechanism is unknown. To clarify the mechanisms, the protein profile of the endometrial secretome was analyzed using two-dimensional difference gel electrophoresis (2D-DIGE). Twenty-seven mares were classified according to whether they were inseminated (AI) or had an intrauterine device (IUD), a water-filled plastic sphere, inserted into the uterus on Day 3 after ovulation. Uterine lavage fluids were collected on Day 15 from pregnant inseminated mares (AI-P; n = 8), non-pregnant inseminated mares (AI-N; n = 4), and m...
Nambo Y, Nagaoka K, Tanaka Y, Nagamine N, Shinbo H, Nagata S, Yoshihara T, Watanabe G, Groome NP, Taya K.In female mammals, inhibin is secreted by the granulosa cells and selectively inhibits secretion of FSH. Although circulating immunoreactive (ir)-inhibin levels decrease after ovulation as a result of the disappearance of its main source, they abruptly increase at the time of ovulation in mares. To investigate the mechanisms responsible for this increase, 50 ml of equine follicular fluid (eFF) was administered into the abdominal cavity of mares during the luteal phase (eFF, n = 4). One hour after treatment, plasma levels of ir-inhibin and inhibin pro-alphaC (but not estradiol-17beta) were sign...
Holcombe SJ, Derksen FJ, Stick JA, Robinson NE.Dorsal displacement of the soft palate (DDSP) is an intermittent obstructive upper airway condition that occurs in athletic horses during high-intensity exercise. The pathogenesis of this condition is unknown, but may involve epiglottic hypoplasia, malformation, or neuromuscular dysfunction. In this paper, we report on investigations into the pathophysiology of DDSP. In 3 separate experiments, Standardbred horses were exercised on a high-speed treadmill at speeds corresponding to 50, 75 and 100% of maximum heart rate. The upper airway was evaluated by videoendoscopy and measurement of tracheal...
Enders AC, Liu IK, Bowers J, Lantz KC, Schlafke S, Suarez S.Fertilization and early development in the horse were studied by recovering oviductal ova at various times after postovulatory mating. Ova collected between 7 and 22 h post coitum (pc) were examined for evidence of fertilizing sperm, cellular changes accompanying fertilization, and pronuclear development. Five ova collected between 7 and 9 h pc contained a marginal metaphase plate, but had no indication of sperm components; three of these, however, showed reduced numbers of cortical granules. Two activated ova (10 and 14 h pc) were in telophase of the second meiotic division, following incorpo...
Anthony J, Waldner C, Grier C, Laycock AR.Dental abnormalities in horses can lead to weight-loss, poor performance, pain, behavioral abnormalities, and illness. Despite this impact, the occurrence and type of dental disease in horse populations is infrequently reported in veterinary medicine. The purpose of this cross-sectional survey of horses presented for slaughter at a processing plant in Western Canada was to measure the prevalence of equine oral abnormalities, examine associations between the most common abnormalities, and consider the relationship between the age of horse and types of abnormalities observed. The horses used in ...
Billinghurst RC, Fretz PB, Gordon JR.Synovial fluid (SF) was collected at 2, 12 and 26 h post racing from 5 Thoroughbred horses (6 joints) with degenerative joint disease. The effects of serial arthrocentesis on SF TNF alpha levels were controlled for by testing, in parallel, site- and time-matched samples from clinically normal horses (i.e. without arthritis). A significant induction in TNF alpha bioactivity was detected in SF from arthritic joints (compared to the control joints) over the 26 h following racing. After subtraction of values for the arthrocentesis control SF, TNF alpha and protein levels and WBC and mononuclear ce...
Nieto JE, Trela J, Stanley SD, Yamout S, Snyder JR.The aim of this study was to determine the pharmacokinetics of amikacin and penicillin G sodium when administered in combination as an intravenous regional limb perfusion (IVRLP) to horses. Seven healthy adult horses underwent an IVRLP in the cephalic vein with 2 g of amikacin sulfate and 10 mill IU of penicillin G sodium diluted to 60 mL in 0.9% saline. A pneumatic tourniquet set at 450 mmHg was left in place for 30 min. Synovial fluid was collected from the metacarpophalangeal joint 35 min and 2, 6, 12, and 24 h after infusion of the antimicrobials. Concentrations of amikacin and penicillin ...
Roberts D, Cotter HVT, Cubeta M, Gilger BC.To determine minimum inhibitory concentrations (MICs) of four fungal species isolated from horses presented with equine fungal keratitis (EFK) in the southeastern United States to previously untested azole, echinocandin, and carboxamide antifungal drugs. Methods: In vitro assays were performed to determine the susceptibility of Aspergillus flavus, A. fumigatus, Fusarium falciforme, and F. keratoplasticum to five antifungal drugs representing three modes of action. Results: Luliconazole exhibited increased growth inhibition against both Aspergillus and Fusarium compared to commonly used, stan...
Barton C, Beck P, Kay R, Teale P, Roberts J.The development of protein biomarkers for the indirect detection of doping in horse is a potential solution to doping threats such as gene and protein doping. A method for biomarker candidate discovery in horse plasma is presented using targeted analysis of proteotypic peptides from horse proteins. These peptides were first identified in a novel list of the abundant proteins in horse plasma. To monitor these peptides, an LC-MS/MS method using multiple reaction monitoring was developed to study the quantity of 49 proteins in horse plasma in a single run. The method was optimised and validated, ...
Allen WR, Wilsher S.Although considerable variation in per cycle pregnancy rates exists between Thoroughbred (TB) stallions, there is little information on factors that may influence this figure. Objective: To assess the influence of month, mare numbers and mating frequency on the fertility of TB stallions standing on studfarms in East Anglia, England. Methods: The daily breeding records of 31 TB stallions mating 3034 mares on 4851 occasions during the 2010 season were surveyed and related to first scan pregnancy rates. The influences of mare book size, month, number of matings per day and mating frequency or abs...
Johnston GCA, Wood KA, Jackson KV, Perkins NR, Zedler ST.Intra-articular (IA) hyaluronic acid (HA) is commonly used to treat equine arthritis. Inflammatory response or "joint flare" is a recognized potential side effect. However, the incidence and severity of inflammation following IA HA injection in horses is not well documented. This study compared the effects of two IA HA formulations of different molecular weight (MW) and a saline control on clinical signs and synovial fluid markers of inflammation in normal equine joints. Eight adult horses each had three healthy fetlock joints randomly assigned to treatment with either 1.4 mega Dalton HA, 0.8 ...
White G, McClure SR, Sifferman R, Holste JE, Fleishman C, Murray MJ, Cramer LG.To determine the effects of 8 days of light to heavy exercise on gastric ulcer development in horses and determine the efficacy of omeprazole paste in preventing gastric ulceration. Methods: Randomized, controlled, multicenter clinical trial. Methods: 102 horses with normal-appearing gastric mucosa on endoscopic examination that were in light to heavy training. Methods: Horses at 4 trial locations were allocated into replicates and sham dosed orally (empty syringe) or treated with a paste formulation of omeprazole (1 mg/kg [0.45 mg/ lb], PO) once daily for 8 days. Training regimens varied amon...
Hollis AR, Boston RC, Corley KT.Neonatal foals succumb rapidly to hypovolaemic shock in comparison to mature horses; they do not consistently increase their heart rate in response to hypotension and respond differently to fluid administration. The hormonal responses to hypovolaemia in the horse and foal require investigation. Objective: The hormonal responses to hypovolaemia and fluid administration differ between mature and neonatal horses. Methods: Five mature horses and 5 neonatal foals fulfilling predetermined criteria for hypovolaemia, were included in the study. A blood sample was taken at admission and after normalisa...
Hassan KA, Galuppo LD, van Hoogmoed LM.To compare bursting strength and failure modes of ventral median abdominal incisions closed with loop suture in a simple continuous pattern using two different suture-bite intervals. Methods: In vitro experiment. Methods: Equine cadavers (n=14; weighing >318 kg; postmortem interval <2 hours). Methods: A template was used to make a 25 cm incision with suture interval and bite size of either 1.0 cm x 1.5 cm or 1.5 cm x 1.5 cm. A 200 L polyurethane bladder was inserted within the abdomen and insufflated to create abdominal wall tension. Celiotomies were closed with a #2 braided lactomer 9-1 conti...
Feary DJ, Magdesian KG, Aleman MA, Rhodes DM.To investigate the clinical, clinicopathologic, and diagnostic characteristics; treatment; and outcome associated with acute traumatic brain injury (TBI) in horses and assess risk factors for nonsurvival in TBI-affected horses. Methods: Retrospective case series. Methods: 34 horses with TBI. Procedures-Medical records of horses that had sustained trauma to the head and developed neurologic signs were reviewed. Data that included signalment, clinicopathologic findings, diagnosis, treatment, and outcome were analyzed. Clinicopathologic variables among horses in survivor and nonsurvivor groups we...
Sah RL, Tsushima RG, Backx PH.We examined the ability of local anesthetics to correct altered inactivation properties of rat skeletal muscle Na+ channels containing the equine hyperkalemic periodic paralysis (eqHPP) mutation when expressed in Xenopus oocytes. Increased time constants of current decay in eqHPP channels compared with wild-type channels were restored by 1 mM benzocaine but were not altered by lidocaine or mexiletine. Inactivation curves, which were determined by measuring the dependence of the relative peak current amplitude after depolarization to -10 mV on conditioning prepulse voltages, could be shifted in...
Carmalt JL, Mortazavi S, McOnie RC, Allen AL, Unniappan S.Equine pituitary pars intermedia dysfunction (PPID) is characterized by hyperplasia of the pars intermedia (PI) melanotrophs of the pituitary gland (PG), and increased production of proopiomelanocortin (POMC). POMC is cleaved by prohormone convertase 1 (PC1) to produce adrenocorticotropic hormone (ACTH), and further processing of ACTH by PC2 to produce alpha-melanocyte stimulating hormone (α-MSH) and corticotropin-like intermediate peptide (CLIP). High plasma ACTH concentrations in horses with PPID might be related to reduced conversion of ACTH to α-MSH by PCs. The hypothesis of this study w...
Koo H, Ryu SH, Ahn HJ, Jung WK, Park YK, Kwon NH, Kim SH, Kim JM, Yoo BW, Choi SI, Davis WC, Park YH.Previous studies have shown that the anionic alkali mineral complex BARODON has an immunoenhancing effect on pigs as an adjuvant and as a nonspecific immunostimulant. Likewise, the equine immune system has been defined with various monoclonal antibodies specific to equine leukocyte differentiation antigens to determine the possibility of enhancing equine resistance to respiratory diseases and promoting other immunostimulatory effects with the application of BARODON. Compared with the control group, after 3 weeks of treatment, BARODON-treated groups showed higher proportions of cells (P < 0.05)...
Beck S, Blunden T, Dyson S, Murray R.It was hypothesised that there is increased blood vessel frequency and proteoglycan staining intensity within the distal aspect of the deep digital flexor tendon (DDFT) in horses with chronic foot pain. Samples of the DDFT from three standardised sites from 10 age-matched mature horses, with chronic foot pain (Group L) or with no history of forelimb lameness (Group N), were collected for this study. A histological analysis of haematoxylin and eosin-stained sections focussed on the frequency and location of blood vessels, while safranin 0 fast green staining was used for semi-quantitative asses...
Timoney JF, Mukhtar MM.The group C streptococci are the most commonly isolated bacteria from disease states in the horse. Important virulence factors of S. equi and S. zooepidemicus are the hyaluronic acid capsule and the antiphagocytic fibrillar M protein located on the surface of the cell wall and extending into and through the capsule. The hyaluronic acid capsule is non-antigenic and so is not involved in protective immunity. The M protein, a superantigen, elicits very strong B and T cell responses that may result in protective immunity mediated by opsonic antibodies in plasma and by locally synthesized IgG and I...
Schwartz EJ, Nanda S, Mealey RH.Lentivirus escape from neutralizing antibodies (NAbs) is not well understood. In this work, we quantified antibody escape of a lentivirus, using antibody escape data from horses infected with equine infectious anemia virus. We calculated antibody blocking rates of wild-type virus, fitness costs of mutant virus, and growth rates of both viruses. These quantitative kinetic estimates of antibody escape are important for understanding lentiviral control by antibody neutralization and in developing NAb-eliciting vaccine strategies.
Salmon SA, Walker RD, Carleton CL, Shah S, Robinson BE.Gardnerella vaginalis has been isolated from women with bacterial vaginosis, from the genital tracts of asymptomatic women, and from several other infected body sites in humans. However, until recently, it has not been isolated from any other animal species. Between June 1988 and October 1989, 31 isolates identified as G. vaginalis and 70 isolates identified as G. vaginalis-like organisms have been recovered from the genital tracts of 93 mares from Michigan and Ohio. Identification was based on biochemical reactions, hemolysis on media containing blood from various animal sources, and suscepti...
Joonè CJ, Bertschinger HJ, Gupta SK, Fosgate GT, Arukha AP, Minhas V, Dieterman E, Schulman ML.Few studies have investigated ovarian function in the mare undergoing porcine zona pellucida (pZP) immunocontraception despite reported ovarian dysfunction in other species. Objective: This study aimed to describe ovarian function and oestrous cyclicity in pony mares following treatment with either the conventional pZP vaccine or a novel recombinant form of the vaccine derived from porcine ZP3 and ZP4 (reZP). In addition, the contraceptive efficacy of pZP vs. reZP was assessed. Methods: Blinded, randomised, prospective clinical trial. Methods: Mares (n = 21) were randomised into 3 groups of 7:...
Barreto Rda S, Rodrigues MN, Carvalho RC, De Oliveira E Silva FM, Rigoglio NN, Jacob JC, Gastal EL, Miglino MA.Musculoskeletal system development involves heterotypical inductive interactions between tendons, muscles, and cartilage and knowledge on organogenesis is required for clarification of its function. The aim of this study was to describe the organogenesis of horse musculoskeletal system between 21 and 105 days of gestation, using detailed macroscopic and histological analyses focusing on essential developmental steps. At day 21 of gestation the skin was translucid, but epithelial condensation and fibrocartilaginous tissues were observed on day 25 of pregnancy. Smooth muscle was seen in lymphat...
Fuerst A, Derungs S, von Rechenberg B, Auer JA, Schense J, Watson J.To describe the treatment of a subchondral bone cyst in the proximal phalanx with parathyroid hormone peptide-enriched fibrin hydrogel in a warmblood filly. The cyst was localized with computer-assisted orthopaedic surgery, then curetted and finally filled with parathyroid hormone fragment peptide 1-34 (PTH(1-34)) covalently attached to a fibrin hydrogel. The cyst healed quickly without any complications. This result supports the hypothesis that PTH(1-34) delivered locally in a fibrin hydrogel may improve the postoperative prognosis of surgical management of subchondral bone cysts in horses. S...
Prescott JF, Hoffman AM.This article summarizes recent advances in understanding of the epidemiology, pathogenesis, clinical and laboratory diagnosis, immunology, treatment, and control of Rhodococcus equi infections in foals. Our understanding of these aspects currently is sufficient to ensure control of this problem on affected farms and in infected foals. More information, however, is needed on factors predisposing foals to R. equi pneumonia, in particular, the nature of the naturally occurring cellular immunodeficiency in foals of 2 to 4 months of age, which also predisposes them to severe respiratory infection w...
