Veterinary research in horses encompasses the study of diseases, health management, and medical treatments specific to equine species. This field investigates various aspects of horse health, including infectious diseases, metabolic disorders, and musculoskeletal conditions. Researchers focus on understanding the pathophysiology of equine ailments, developing diagnostic tools, and evaluating therapeutic interventions. The study of horse health also involves examining preventive measures such as vaccination protocols and nutritional management to promote overall well-being. This page collects peer-reviewed research studies and scholarly articles that explore the diverse areas of veterinary science related to horses, providing insights into disease mechanisms, treatment strategies, and advancements in equine healthcare.
Takahashi K, Mukai K, Takahashi Y, Ebisuda Y, Sugiyama F, Hatta H, Kitaoka Y.To explore the molecular mechanisms underlying oxygen-dependent regulation of skeletal muscle adaptations, eight Thoroughbred horses performed 2 min of exercise at a velocity corresponding to 95% maximal O2 uptake under a normoxic condition, while using inspired O2 levels of 0.21 (normoxia), 0.26 (hyperoxia) or 0.16 (hypoxia). At the end of the exercise, arterial O2 saturation was significantly higher with hyperoxia and lower with hypoxia than with normoxia. However, no significant difference in plasma lactate or muscle glycogen concentrations was observed across the O2 conditions. A metabol...
Dobbs EC, Acutt EV, Scharf AM, Manzi TJ, Stefanovski D, Bills KW.To investigate the effects of varied feed consistency and administration of xylazine or N-butylscopolammonium bromide on 3 phases of swallowing and characterize esophageal motility following barium administration via nasoesophageal tube. Unassigned: 8 healthy horses were enrolled for 2.5 consecutive weeks. Horses underwent experimental videofluoroscopic swallow studies before and after sedated and anticholinergic interventions. Esophageal motility was assessed with barium administered via nasoesophageal tube and with barium-admixed feedstuffs of 3 consistencies with increasing viscosity. Phase...
Anger-Håål C, Fjordbakk CT, Ekstrand C, Skedsmo FS, Rørtveit R.Insulin dysregulation is a hallmark of equine metabolic syndrome (EMS), and in recent years, pharmacological treatment with sodium-dependent glucose transporter 2 inhibitors (SGLT2i) have shown promise in reducing the risk of hyperinsulinemia-associated laminitis in horses diagnosed with EMS. In humans and laboratory animals, this transporter protein is responsible for the majority of renal tubular glucose reabsorption, however, the presence of this and the related sodium-dependent glucose transporter 1 (SGLT1) have not yet been studied in equine kidneys. Additionally, studies in humans and la...
Semanchik PL, Wesolowski LT, Artman JL, Seward RL, Beer C, Barnes ED, White-Springer SH.Reactive oxygen species are normal by-products of cellular metabolism but may have detrimental effects on cellular matrices and excite inflammatory pathways when overproduced. To test the hypothesis that supplementation of an herbal extract combination would: 1) improve antioxidant status; 2) increase anti-inflammatory cytokines; and 3) decrease pro-inflammatory cytokines, 40 mature, sedentary stock-type horses (32 mares, 8 geldings, mean±SD; 15.7 ± 4.9 yr, 519 ± 46 kg) were stratified by age, sex, and body weight and randomly assigned to one of four dietary treatment groups for 5...
Parker M, Arnade H, Parker JL, Gordon J, Peroni JF.Investigation of alternative antibiotic therapies is critical for the future of medicine. Platelet lysate (PL) is a blood product that has shown antibiotic potential, which could be used to augment or replace current antibiotics. Objective: To compare the effects of equine PL versus antibiotics on growth of clinically isolated antibiotic resistant bacteria. We hypothesized that PL would exert an antimicrobial effect on equine bacterial isolates resistant to antibiotics. Methods: In vitro experimental study. Platelets were collected via apheresis from nine donor horses and underwent two freeze-...
Tripon MA, Manolăchescu D, Papuc I, Daradics Z, Crecan CM.Emotional contagion between horses and humans is a key aspect of their interaction, influencing welfare, training, and therapy, yet current methods for measuring this phenomenon lack standardization and consistency. Objective: The aim of this study was to verify what methods are used to assess emotional contagion in horse-human interactions, and what outcomes have been reported. Methods: A systematic search of Google Scholar, Web of Science, Scopus, PubMed, and Science Direct was conducted up to March 2024. Peer-reviewed studies assessing emotional transfer through behavioral and/or physiologi...
Sellke L, Ludewig E, Handschuh S, Witter K.In a previous study on hoof biometry, we found that mathematical correction of measuring results from radiographs did not lead to complete correspondence to computed tomography (CT) results. The present study investigates this finding by comparing 13 measures of six cadaveric equine digits collected with the following workflows: radiographs with 1 and 2 m focus-object distance (FOD) (Xray 1 m/2 m), computed tomography images in planes defined based on anatomical landmarks (CTw), simulated radiographs based on the tomography dataset (virtual 120-mm slabs, Xray Sim) and measurements based ...
Arevalo-Turrubiarte M, Edling CE, Moller-Levet C, Forbes B, Kemp V, Weir J, Marr C, Lewis R, Jeevaratnam K.The initiation and maintenance of atrial fibrillation have been associated with physiological alterations in myocardial sleeves of the pulmonary veins (PVs). Gene expression profiles of the myocardial sleeves of the PVs in healthy (n = 3) and paroxysmal atrial fibrillation (PAF) (n = 6) thoroughbred horses (Equus caballus) were studied. Tissue collected from the left superior PV, adjacent to the left atrium, was analyzed by RNA sequencing. Gene Set Enrichment Analysis demonstrated positive enrichment of gene ontology biological processes related to muscle and endothelial cell development, cell...
Leibeck R, Lehman J, Birmingham S.Whole-body vibrational therapy (WBV) is well-studied in people, but there is a paucity of research regarding its effect on horses. It is suggested that the use of WBV in horses increases performance, aids in recovery, and stimulates nerves, bones, and muscles in ways that normal exercise does not. Objective: The purpose of this pilot study was to determine if frequent WBV therapy sessions affect mechanical nociceptive thresholds based on pressure algometry in horses without clinical signs of lameness or back pain. Methods: The mechanical nociceptive thresholds (MNTs) were measured for 5 horses...
Feng M, Hall TJ, MacHugh DE, Katz LM, Hill EW.Early skeletal muscle development is critical for young racehorses, yet research on the transcriptional changes during this period is limited. Additionally, the impact of age on the transcriptional response to exercise training in equine athletes is not well understood. A transcriptome-wide analysis of differential gene expression in skeletal muscle was performed for five untrained Thoroughbred horses sampled at rest at two years old (UR2) and three years old (UR3). A total of 136 differentially expressed genes (DEGs) were identified, with 95 increased and 41 decreased in expression. GO enrich...
Hoerdemann M, Sahoo DK, Allbaugh RA, Kubai MA.To assess if an inexpensive, commercially available ultraviolet C (UV-C) light device with a peak emission of 275 nm can inhibit equine keratomycosis-associated pathogens located at different corneal depths in an ex vivo model. Methods: A controlled, randomized experimental design. Aspergillus fumigatus and Fusarium solani isolates were inoculated in fresh bovine corneoscleral transplants, superficially or at 450 μm of stromal depth for the ulcerative keratomycosis or stromal abscess model, respectively. After a minimum of 18 h of incubation, treatment groups received 15 s of UV-C li...
Dantas FTDR, Canisso IF, Feijó LS, de Vasconcelos PMF, Campos ML, Ulanov AV, Li Z, Pizzi GLBL, Nogueira CEW, Curcio BR.Doxycycline is widely used in equine medicine, yet data on its pharmacokinetics and safety during late gestation are scarce. We investigated the pharmacokinetics, fetoplacental diffusion, and safety of compounded oral doxycycline in late-term pregnant mares. In the first experiment, six mares at 300 days of gestation received a single oral dose (10 mg/kg), and plasma concentrations were measured using LC-MS/MS. Pharmacokinetic analysis using non-compartmental and compartmental models showed rapid absorption, with a mean Cmax of about 6000 ng/mL reached within 0.8 h and a terminal half-life ...
Carmona JU, López C, Argüelles D.(1) Background: Platelet-rich plasma (PRP) therapy has become a cornerstone of equine regenerative medicine, yet significant methodological variability compromises reproducibility and clinical comparability. (2) Methods: This scoping review systematically mapped and analyzed peer-reviewed studies describing equine PRP preparation methods and commercial systems (2000-2024) following PRISMA-ScR guidelines. (3) Results: Twenty-four studies met the inclusion criteria, encompassing 317 horses and both manual and commercial devices. Double-spin manual protocols predominated, though centrifugation pa...
Pepper B, North E, Culwell J, Nicodemus MC, Cavinder C, Harvey K, Williams T.Due to the incorporation of the Golden American Saddlebred Horse Association (GASHA) into the American Saddlebred Horse and Breeders Association (ASHBA), breeding for coat color has become more challenging for horse breeders. However, with this merger, pedigree tracing can be of value in pinpointing foundation bloodlines within the GASHA that influence production of the golden coat phenotype. Objective: The study objective was to document the historical origins of the GASHA through pedigree tracing to determine the influence of dilution alleles that produce the golden coat phenotype. Methods: ...
Harpke M, Brangsch H, Melzer F.In Germany, Contagious Equine Metritis (CEM) is a persistent problem in equine populations. The often subclinical nature of the disease, which is caused by the bacterium Taylorella equigenitalis, poses a problem for the breeding industry. However, there is a lack of knowledge about the genomic diversity of the pathogen in Germany, as studies on the genome level are lacking. Thus, in this study we sequenced 63 T. equigenitalis isolates from a strain collection and contemporary clinical isolates from before 2007-2024. Most of these isolates came from Icelandic horses in southern Germany. Based...
Southwood LL, Long A, Perez J, Daniel S, Bittinger K, Aitken M, Redding L.Based on human studies, surgical antimicrobial (AMD) prophylaxis (SAP) beyond 24 h is unnecessary and potentially detrimental. Objective: To compare clinical and microbiological outcomes in patients receiving 24- or 72-h of SAP for colic surgery. Methods: Prospective randomised clinical trial. Methods: Horses that recovered from colic surgery were considered. Exclusion criteria were (1) age <2 years; (2) Miniature Horses, pony, and draught breeds; (3) azotaemia; (4) recent hospitalisation, colic surgery, or AMDs; (5) local AMD administration. Eligible horses were randomly assigned to recei...
Page AE, McPeek JL, Carattini S, McGreevy E, Adam E.The goal of this project was to examine the metabolic effects of IA methylprednisolone acetate (MPA) following injection into multiple low-motion joints. Unassigned: Six 3-year-old geldings without pituitary pars intermedia dysfunction or insulin dysregulation were randomly injected with 20 mg of IA MPA/joint (80 mg total; bilateral distal hock joints) or an equal volume of saline. Serial blood samples were collected for resting ACTH, cortisol, insulin, and glucose, as well as insulin and glucose following repeated low-dose oral sugar tests. Treatments were crossed over after a 6-week washout,...
Norton EM, Plumb S, Shane D, Smalley L, McKendry K, Scharf B, Zemel M.Supplements claiming to improve metabolic profiles in equine metabolic syndrome (EMS) often lack scientific validation. Objective: To evaluate the effect of a supplement containing leucine, resveratrol and pyridoxine on the metabolic profile in ponies with EMS. Methods: Unmasked randomised, placebo-controlled field trial. Methods: Thirty-eight ponies completed the trial across five farms. Ponies were age and sex matched per farm and randomly assigned to the supplement (n = 20) or placebo group (n = 18) with owners masked to group assignments. Ponies were sampled at days -1/0 (T1), 7/8 ...
Frey K, Perlini M, Reed R.Intravenous (IV) contrast administration during computed tomography (CT) of the equine head is routinely performed to delineate the extent of disease and differentiate between vascular and nonvascular tissue. Current equine scan protocols are extrapolated from human and canine studies. There have been no prospective equine studies describing the optimal time to image the patient after administration of contrast or the optimal site of contrast administration. Therefore, the current postcontrast times to scan and sites of contrast administration may not be appropriate for use in horses. The obje...
El-Geneady MA, Ramadan RM, Mahdy OA, Kamel MS, Salem MA.Hippobosca equina, a common ectoparasite of horses, poses a significant challenge to equine health worldwide. This study provides a molecular characterization of H. equina and examines its impact on host immune responses and oxidative stress. Genetic analysis of samples from various regions revealed notable homogeneity, indicating limited genetic variation among populations. Phylogenetic analysis demonstrated close genetic relationships among sequences from Egypt, France, Kazakhstan and Portugal, while also showing comparable but more distant identities to sequences from China, Denmark, Finlan...
Satué K, Fauci D, Fazio E, Velasco-Martínez MG, Bruschetta G, Medica P.This study investigates sequential changes in serum protein fractions during gestation in 31 pregnant Spanish Purebred mares compared to 15 non-pregnant control. Total serum proteins (TSP) were measured using the Biuret method, while albumin (ALB), total globulins (tGLOB), and their subfractions (α₁, α₂, β₁, β₂, γ-GLOB) were analyzed by agarose gel electrophoresis. Pregnant mares showed significant changes in serum protein profiles throughout gestation. TSP and tGLOB concentrations increased from mid to late pregnancy (months 6-11), while ALB concentrations declined between months...
Mendoza Cerna MN, Anderson H, Avni G, Kahila Bar-Gal G, Juras R, Raudsepp T.Robertsonian translocations (ROBs) or centric fusions of acrocentric chromosomes are the most common structural chromosomal rearrangements in mammals. ROBs are of medical and veterinary concern because of associated subfertility and congenital disorders but are also of interest as a mechanism of chromosome and karyotype evolution. While ROBs are well documented in humans, mice, and cattle/bovids, they are extremely rare in horses, despite the 18 acrocentric chromosomes in the horse karyotype. Methods: We characterize the case using conventional and molecular cytogenetic approaches and DNA anal...
Silva JG, Martins KR, Rahal NM, Schuch LFD, Cunha RC, Meireles MCA.Neorickettsia risticii, an obligate intracellular bacterium, is the causative agent of Potomac Horse Fever (PHF) - a systemic, acute, and potentially fatal diarrheal disease. This pathogen is an endosymbiont of digenetic trematodes, with freshwater snails playing a role in its biological cycle. The disease exhibits endemic and seasonal patterns, primarily affecting horses in wetlands during warmer months, and has been documented in the United States, Canada, Europe, and South America. Previous studies confirmed the pathogen's presence in herds from southern Brazil via serology and PCR; however...
Otero JC, Neild DM, Ferrante AA, Gambarotta MC, Caldevilla ML.Glycerol, a penetrating cryoprotectant, is most employed for deep freezing spermatozoa. However, it can induce toxic, chemical, and osmotic effects, altering the lipid structure of the sperm membrane. Rapid glycerol addition has been demonstrated to have fewer toxic effects than its removal. Objective: To minimize both the toxic and osmotic effects of glycerol on equine sperm through post-thaw dilution using two different extenders. Methods: Samples of equine semen frozen with 5% glycerol from nine stallions were thawed, re-diluted 1:2, and incubated for 30 minutes at 22°C in Tyrodes (Tyr) an...
da Silva Rocha MB, Avelar BR, Martins Dos Santos GC, Ferreira TP, de Sousa Vieira T, de Oliveira GF, Gomes BT, Klafke GM, Correia TR, Cid YP, Scott FB.The objective of this study was to standardize a stall-trial methodology for horses in order to evaluate the pharmacokinetics and efficacy of a 1 % fipronil pour-on formulation against Dermacentor nitens. Brazilian pony breed horses were housed in individual stalls within a covered barn and artificially infested with D. nitens larvae on alternate days from day -31 to -1 before treatment. The animals were treated on day 0 with a fipronil 1 % pour-on at a dose of 1 mg/Kg body weight. To determine the therapeutic efficacy, the number of engorged females naturally detached from control and t...
Jandová V, Huber N, AlMheiri FG, Bábor K, Trachsel DS.Stress represents a serious health and welfare concern; however, its objective assessment remains difficult. The equine gastric ulcer syndrome (EGUS) and orthopedic diseases that cause pain are among stress associated diseases in equine medicine. The leukocyte coping capacity (LCC) quantifies oxygen radical generation of neutrophil granulocytes which is altered under stress. Therefore, LCC could be a novel biomarker for stress in horses and we hypothesized that horses with stress associated diseases would have lower LCC values in comparison to horses without these diseases. Methods: In this ob...
James AL, Vettorato E, Moura RA, Azevedo TMBPR, Mallicote MF, Chiavaccini L.Sedation with α₂-agonists can impair microcirculation and oxygen delivery. This prospective randomized crossover study investigated whether administering acepromazine maleate before detomidine hydrochloride maintains higher peripheral tissue oxygen saturation (StO₂) in sedated horses. Eight healthy adult horses randomly received intravenous detomidine (10 μg/kg) either alone (D) or in combination with acepromazine (20 μg/kg; DA), with a one-week washout. Hemoglobin concentration and central venous oxygen saturation (ScvO₂) were measured at baseline. Tissue oxygen saturation, tissue ...
McGilvray TA, Stevens KB, Spence KL, Rosanowski SM, Slater J, Cardwell JM.The widespread assumption that there is minimal potential for pathogen transmission between British racehorse and sport horse populations remains unverified by empirical evidence. Objective: To characterise spatiotemporal patterns of horse attendance at racing and other sport events in Great Britain in 2018. Methods: Spatiotemporal analysis. Methods: Publicly available data from British Horseracing Authority, British Dressage, British Eventing, Endurance GB, and British Showjumping events in Great Britain during 2018 were analysed. Horse attendance was summarised by discipline, month, and seas...
Aiche S, Chikhaoui M, Smail F, Benamor N, Benia AR.Pregnancy causes increased oxidative stress in mares, possibly harming both the mare and the foal, whereas the effects of different exercise levels on oxidative stress and lipid metabolism during pregnancy remain unclear. Objective: For this reason, the aim of this research was to explore the impacts of different training intensities on oxidative stress and lipid metabolism during pregnancy. Methods: The study comprised 22 clinically normal Purebred Arabian mares from Algeria, which were divided into three groups according to age and exercise frequency. Blood samples were collected during both...
Edson D, Field H, McMichael L, Vidgen M, Goldspink L, Broos A, Melville D, Kristoffersen J, de Jong C, McLaughlin A, Davis R, Kung N, Jordan D....Pteropid bats or flying-foxes (Chiroptera: Pteropodidae) are the natural host of Hendra virus (HeV) which sporadically causes fatal disease in horses and humans in eastern Australia. While there is strong evidence that urine is an important infectious medium that likely drives bat to bat transmission and bat to horse transmission, there is uncertainty about the relative importance of alternative routes of excretion such as nasal and oral secretions, and faeces. Identifying the potential routes of HeV excretion in flying-foxes is important to effectively mitigate equine exposure risk at the bat...
Ali A, Khan MA, Zahid H, Yaseen PM, Qayash Khan M, Nawab J, Ur Rehman Z, Ateeq M, Khan S, Ibrahim M.Although ticks prevalent in various agro-systems of Pakistan are associated with economic losses, information is still missing about the tick's diversity, hosts they infest, seasonal dynamics and molecular phylogeny of in Khyber Pakhtunkhwa (KP) Pakistan. This study for the first time enlisted ticks infesting diverse hosts including humans in various regions of KP. A total of 8,641 ticks were collected across the northern, southern and central regions of KP and were morpho-taxonomically categorized into six genera comprising 17 species, ( = 3,584, 42%), ( = 2,253, 27%) ( = 1,342, 16%), ( =...
Witte TH, Knill K, Wilson AM.Measurement of peak vertical ground reaction force (GRFz) from multiple limbs simultaneously during high-speed, over-ground locomotion would enhance our understanding of the locomotor mechanics of cursorial animals. Here, we evaluate the accuracy of predicting peak GRFz from duty factor (the proportion of the stride for which the limb is in contact with the ground). Foot-mounted uniaxial accelerometers, combined with UHF FM telemetry, are shown to be practical and accurate for the field measurement of stride timing variables, including duty factor. Direct comparison with the force plate produc...
Carpenter S, Mellor PS, Fall AG, Garros C, Venter GJ.African horse sickness virus (AHSV) is a lethal arbovirus of equids that is transmitted between hosts primarily by biting midges of the genus Culicoides (Diptera: Ceratopogonidae). AHSV affects draft, thoroughbred, and companion horses and donkeys in Africa, Asia, and Europe. In this review, we examine the impact of AHSV critically and discuss entomological studies that have been conducted to improve understanding of its epidemiology and control. The transmission of AHSV remains a major research focus and we critically review studies that have implicated both Culicoides and other blood-feeding...
Knowles DP, Kappmeyer LS, Haney D, Herndon DR, Fry LM, Munro JB, Sears K, Ueti MW, Wise LN, Silva M, Schneider DA, Grause J, White SN, Tretina K....A novel apicomplexan parasite was serendipitously discovered in horses at the United States - Mexico border. Phylogenetic analysis based on 18S rDNA showed the erythrocyte-infective parasite to be related to, but distinct from, Theileria spp. in Africa, the most similar taxa being Theileria spp. from waterbuck and mountain zebra. The degree of sequence variability observed at the 18S rDNA locus also suggests the likely existence of additional cryptic species. Among described species, the genome of this novel equid Theileria parasite is most similar to that of Theileria equi, also a pathogen of...
Costa MC, Weese JS.The equine intestinal tract contains a complex microbial population (microbiota) that plays an important role in health and disease. Despite the undeniable importance of a 'normal' microbiota, understanding of the composition and function of this population is currently limited. As methods to characterize the microbiota and its genetic makeup (the microbiome) have evolved, the composition and complexity of this population are starting to be revealed. As is befitting a hindgut fermenter, members of the Firmicutes phylum appear to predominate, yet there are significant populations of numerous ot...
Kaplan RM.Suppressive anthelmintic treatment strategies originally designed to control Strongylus vulgaris in horses were extremely successful in reducing morbidity and mortality from parasitic disease. Unfortunately, this strategy has inadvertently resulted in the selection of drug-resistant cyathostomes (Cyathostominea), which are now considered the principal parasitic pathogens of horses. Resistance in the cyathostomes to benzimidazole drugs is highly prevalent throughout the world, and resistance to pyrantel appears to be increasingly common. However, there are still no reports of ivermectin resista...
Proops L, McComb K.It has recently been shown that some non-human animals can cross-modally recognize members of their own taxon. What is unclear is just how plastic this recognition system can be. In this study, we investigate whether an animal, the domestic horse, is capable of spontaneous cross-modal recognition of individuals from a morphologically very different species. We also provide the first insights into how cross-modal identity information is processed by examining whether there are hemispheric biases in this important social skill. In our preferential looking paradigm, subjects were presented with t...
Prokhorov NS, Riccio C, Zdorovenko EL, Shneider MM, Browning C, Knirel YA, Leiman PG, Letarov AV.Bacteriophages recognize and bind to their hosts with the help of receptor-binding proteins (RBPs) that emanate from the phage particle in the form of fibers or tailspikes. RBPs show a great variability in their shapes, sizes, and location on the particle. Some RBPs are known to depolymerize surface polysaccharides of the host while others show no enzymatic activity. Here we report that both RBPs of podovirus G7C - tailspikes gp63.1 and gp66 - are essential for infection of its natural host bacterium E. coli 4s that populates the equine intestinal tract. We characterize the structure and funct...
Bi X, Li G, Doty SB, Camacho NP.The orientation of collagen molecules is an important determinant of their functionality in connective tissues. The objective of the current study is to establish a method to determine the alignment of collagen molecules in histological sections of cartilage by polarized Fourier transform infrared imaging spectroscopy (FT-IRIS), a method based on molecular vibrations. Methods: Polarized FT-IRIS data obtained from highly oriented tendon collagen were utilized to calibrate the derived spectral parameters. The ratio of the integrated areas of the collagen amide I/II absorbances was used as an ind...
Thompson JM, Whitmore AC, Konopka JL, Collier ML, Richmond EM, Davis NL, Staats HF, Johnston RE.Vaccination represents the most effective control measure in the fight against infectious diseases. Local mucosal immune responses are critical for protection from, and resolution of, infection by numerous mucosal pathogens. Antigen processing across mucosal surfaces is the natural route by which mucosal immunity is generated, as peripheral antigen delivery typically fails to induce mucosal immune responses. However, we demonstrate in this article that mucosal immune responses are evident at multiple mucosal surfaces after parenteral delivery of Venezuelan equine encephalitis virus replicon pa...
Lupo A, Saras E, Madec JY, Haenni M.In Asian countries, blaCTX-M-55 is the second most common ESBL-encoding gene. blaCTX-M-55 frequently co-localizes with fosA and rmtB genes on epidemic plasmids, which remain sporadic outside Asia. During 2010-13, we investigated CTX-M-55-producing Escherichia coli isolates and their co-resistance to fosfomycin, aminoglycosides, fluoroquinolones and colistin as part of a global survey of ESBLs in animals in France. blaCTX-M-55, fosA, rmtB and plasmidic quinolone and colistin resistance genes were characterized by PCR, sequencing and hybridization experiments. Plasmids were classified according ...
Cross AR, Higson FK, Jones OT, Harper AM, Segal AW.1. The absorption coefficient of human neutrophil plasma-membrane reduced-minus-oxidized cytochrome b-245 was determined [delta epsilon (mM; 559-540 nm) = 21.6 cm-1]. 2. Neutrophil polymorphonuclear leucocytes (neutrophils) were prepared from human, ox, horse and pig blood. In each case plasma-membrane fractions were found to contain low-potential cytochrome b. When membranes from horse neutrophils were incubated anaerobically with either NADH or NADPH the cytochrome b became reduced. Prior stimulation of the cells with phorbol myristate acetate did not increase the rate or extent of cytochrom...
Eddy AL, Van Hoogmoed LM, Snyder JR.Equine thermography has increased in popularity recently because of improvements in thermal cameras and advances in image-processing software. The basic principle of thermography involves the transformation of surface heat from an object into a pictorial representation. The colour gradients generated reflect differences in the emitted heat. Variations from normal can be used to detect lameness or regions of inflammation in horses. Units can be so sensitive that flexor tendon injuries can be detected before the horse develops clinical lameness. Thermography has been used to evaluate several dif...
Pfau T, Witte TH, Wilson AM.Biomechanical studies often employ optical motion capture systems for the determination of the position of an object in a room-based coordinate system. This is not ideal for many types of study in locomotion since only a few strides may be collected per ;trial', and outdoor experiments are difficult with some systems. Here, we report and evaluate a novel approach that enables the user to determine linear displacements of a proprietary orientation sensor during cyclical movement. This makes experiments outside the constraints of the laboratory possible, for example to measure mechanical energy ...
Giguère S, Cohen ND, Chaffin MK, Hines SA, Hondalus MK, Prescott JF, Slovis NM.Pneumonia is a major cause of disease and death in foals. Rhodococcus equi, a gram-positive facultative intracellular pathogen, is a common cause of pneumonia in foals. This article reviews the clinical manifestations of infection caused by R. equi in foals and summarizes current knowledge regarding mechanisms of virulence of, and immunity to, R. equi. A complementary consensus statement providing recommendations for the diagnosis, treatment, control, and prevention of infections caused by R. equi in foals can be found in the same issue of the Journal.
Hilbe M, Herrsche R, Kolodziejek J, Nowotny N, Zlinszky K, Ehrensperger F.Borna disease virus (BDV) is the causative agent of severe T-cell-mediated meningoencephalitis in horses, sheep, and other animal species in central Europe. Here we report the first unequivocal detection of a BDV reservoir species, the bicolored white-toothed shrew, Crocidura leucodon, in an area in Switzerland with endemic Borna disease.
Barberini DJ, Freitas NP, Magnoni MS, Maia L, Listoni AJ, Heckler MC, Sudano MJ, Golim MA, da Cruz Landim-Alvarenga F, Amorim RM.Studies with mesenchymal stem cells (MSCs) are increasing due to their immunomodulatory, anti-inflammatory and tissue regenerative properties. However, there is still no agreement about the best source of equine MSCs for a bank for allogeneic therapy. The aim of this study was to evaluate the cell culture and immunophenotypic characteristics and differentiation potential of equine MSCs from bone marrow (BM-MSCs), adipose tissue (AT-MSCs) and umbilical cord (UC-MSCs) under identical in vitro conditions, to compare these sources for research or an allogeneic therapy cell bank. Methods: The BM-MS...
Giguère S, Viel L, Lee E, MacKay RJ, Hernandez J, Franchini M.Work in humans and laboratory animals has identified a central role for cytokines and chemokines in development and persistence of lower airway inflammation. The objectives of this study were to determine interleukin (IL)-1 beta, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, interferon (IFN)-gamma and tumor necrosis factor (TNF)-alpha induction in bronchoalveolar lavage (BAL) of control horses and horses with heaves both during remission and exacerbation of the disease, and to determine the effect of therapy with inhaled fluticasone propionate on the cytokine profile of horses with heaves. IL-1 beta an...
Lewis NS, Daly JM, Russell CA, Horton DL, Skepner E, Bryant NA, Burke DF, Rash AS, Wood JL, Chambers TM, Fouchier RA, Mumford JA, Elton DM, Smith DJ.Equine influenza virus is a major respiratory pathogen in horses, and outbreaks of disease often lead to substantial disruption to and economic losses for equestrian industries. The hemagglutinin (HA) protein is of key importance in the control of equine influenza because HA is the primary target of the protective immune response and the main component of currently licensed influenza vaccines. However, the influenza virus HA protein changes over time, a process called antigenic drift, and vaccine strains must be updated to remain effective. Antigenic drift is assessed primarily by the hemagglu...
Corning S.The small strongyles of horses, also known as cyathostomins, are considered the most prevalent and pathogenic parasites of horses today. The clinical syndrome of larval cyathostominosis which occurs as a result of mass emergence of inhibited stages has a high fatality rate despite the best standard of care given to affected horses. Management of the challenge level of cyathostomins to prevent the syndrome is preferable. Many different management programmes have been tried over the past two decades, with mixed success. Programmes have relied heavily on repeated use of anthelmintic treatments th...
Rubin JE, Pitout JD.Organisms in the family Enterobactericeae including, Escherichia coli, commonly cause community and hospital-associated infections in both humans and companion animals. The increasing prevalence of infections with organisms producing broad spectrum β-lactamses such as the ESBLs (particularly the CTX-M type), AmpC and carbapenemase enzymes are threatening the future of the β-lactam drugs. While a number of organisms within the Enterobacteriaceae producing these enzymes have been isolated from cats, dogs and horses, E. coli, including isolates indistinguishable from strains found in people, ha...
Carter RA, Treiber KH, Geor RJ, Douglass L, Harris PA.The ability to predict ponies at increased risk of laminitic episodes, when exposed to nutrient dense pasture, would facilitate management to avoid disease. Objective: To identify variables and clinically useful cut-off values with reproducible diagnostic accuracy for the prediction of ponies that subsequently developed laminitis when exposed to nutrient dense pasture. Methods: A cohort of predominantly Welsh and Dartmoor ponies from a closed herd was evaluated in March 2006 (n = 74) and March 2007 (n = 57). Ponies were categorised as never laminitic or previously laminitic according to report...
Kasashima Y, Takahashi T, Smith RK, Goodship AE, Kuwano A, Ueno T, Hirano S.Overstrain injuries to the superficial digital flexor tendon (SDFT) and suspensory ligament (SI) are among the most common musculoskeletal injuries which contribute to the considerable wastage of racing Thoroughbreds. Many epidemiological studies have demonstrated the prevalence of and risk factors for tendon injury when racing but have not included those injuries sustained during training. However, since tendon injury during training is seen commonly in clinical practice, it is appropriate to determine the overall prevalence of tendon injury sustained during both training and racing. Objectiv...
Gibb Z, Lambourne SR, Aitken RJ.The relationship between stallion fertility and oxidative stress remains poorly understood. The purpose of this study was to identify criteria for thoroughbred fertility assessment by performing a logistical regression analysis using "dismount" sperm parameters as predictors and weekly per-cycle conception rate as the dependent variable. Paradoxically, positive relationships between fertility and oxidative stress were revealed, such that samples that produced pregnancies exhibited higher rates of 8-hydroxy-2'-deoxyguanosine release (1490.2% vs. 705.5 pg/ml/24 h) and lower vitality (60.5% vs. 6...
Guest DJ, Smith MR, Allen WR.Autologous mesenchymal progenitor cells (MPCs) purified from bone marrow aspirates are being used in the treatment of superficial digital flexor tendon (SDFT) injuries in the horse with promising results. In this study the fate of autologous and allogeneic MPCs following injection into the SDFT was monitored by stable transfection of MPCs with green fluorescent protein (GFP). Small lesions were created manually in one forelimb SDFT of 2 horses and injected with autologous MPCs, allogeneic MPCs or bone marrow supernatant alone. Post mortem examinations performed after 10 or 34 days revealed GFP...
Metallinos DL, Bowling AT, Rine J.Lethal White Foal Syndrome is a disease associated with horse breeds that register white coat spotting patterns. Breedings between particular spotted horses, generally described as frame overo, produce some foals that, in contrast to their parents, are all white or nearly all white and die shortly after birth of severe intestinal blockage. These foals have aganglionosis characterized by a lack of submucosal and myenteric ganglia from the distal small intestine to the large intestine, similar to human Hirschsprung Disease. Some sporadic and familial cases of Hirschsprung Disease are due to muta...
Wilson AM, McGuigan MP, Su A, van Den Bogert AJ.The muscular work of galloping in horses is halved by storing and returning elastic strain energy in spring-like muscle-tendon units.These make the legs act like a child's pogo stick that is tuned to stretch and recoil at 2.5 strides per second. This mechanism is optimized by unique musculoskeletal adaptations: the digital flexor muscles have extremely short fibres and significant passive properties, whereas the tendons are very long and span several joints. Length change occurs by a stretching of the spring-like digital flexor tendons rather than through energetically expensive length changes...
Möstl E, Messmann S, Bagu E, Robia C, Palme R.After 14C-labelled cortisol infusion in ponies and pigs, faecal samples were collected. Extraction of 0.5 g faeces with 5 ml 80-90% methanol yielded the highest radioactivity in the supernatant. Most of the metabolites were ether soluble. After high performance liquid chromatography (HPLC), the presence of immunoreactive metabolites was demonstrated by measuring each HPLC fraction using enzyme immunoassays for cortisol, corticosterone and 11-oxoaetiocholanolone. Only the assay for 11-oxoaetiocholanolone revealed peaks with co-eluting radioactivity. For biological validation of the test system,...
