Equine diseases encompass a wide range of health conditions that can affect horses, including infectious diseases, metabolic disorders, and genetic conditions. These diseases can impact the overall health, performance, and well-being of horses. Common equine diseases include equine influenza, equine herpesvirus, laminitis, and equine metabolic syndrome. Diagnosis and management of these diseases often require a combination of clinical evaluation, laboratory testing, and appropriate treatment strategies. This page gathers peer-reviewed research studies and scholarly articles that explore the etiology, pathophysiology, diagnosis, and treatment options for various equine diseases, providing valuable insights for veterinarians and researchers in the field.
de Laat MA, Fitzgerald DM, Sillence MN, Spence RJ.Equine insulin dysregulation (ID) is a common and poorly understood disorder that increases the risk of laminitis. Recent data show that the condition may be associated with alteration of the enteroinsular axis and enhanced glucose bioavailability. Upregulation of glucagon-like peptide-2 (GLP-2), an intestinotrophic peptide, leads to enhanced nutrient uptake and metabolic dysfunction in other species. Objective: The study aimed to 1) determine whether GLP-2 is differentially expressed in insulin-dysregulated ponies, compared with healthy ponies, and 2) confirm intestinal expression of the GLP-...
Varela E, Rey J, Plaza E, Muñoz de Propios P, Ortiz-Rodríguez JM, Álvarez M, Anel-López L, Anel L, De Paz P, Gil MC, Morrell JM....Contaminating bacteria present in stallion ejaculates may compromise sperm quality during storage. Different procedures have been used to reduce the load of microorganisms in semen and avoid bacterial growth during storage. The aims of this study were: 1) to evaluate different techniques to eliminate bacteria in semen 2) to study the relationship between total microflora load (TML) and ROS production; and 3) to determine if TML affects the functionality of cool-stored sperm. Ejaculates from 11 stallions were split and processed in 3 ways: A. extended semen; B. conventional centrifuged semen, a...
Durham AE.Therapeutic drug monitoring and minimum inhibitory concentration (MIC) data allow more informed use of gentamicin. Objective: To measure peak and trough serum gentamicin concentrations in horses after a 6.6 mg/kg dose of gentamicin given IV and the MIC of gentamicin of bacteria for which gentamicin might be selected. Methods: Retrospective analysis of hospital records. Peak and trough plasma gentamicin concentrations were measured after 6.6 mg/kg gentamicin IV in 339 hospitalized horses. The MIC of gentamicin was measured for 503 isolates from ambulatory practice and 33 from hospital practice....
Elzinga S, Reedy S, Barker VD, Chambers TM, Adams AA.Obesity is an increasing problem in the equine population with recent reports indicating that the percentage of overweight horses may range anywhere from 20.6-51%. Obesity in horses has been linked to more serious health concerns such as equine metabolic syndrome (EMS). EMS is a serious problem in the equine industry given its defining characteristics of insulin dysregualtion and obesity, as well as the involvement of laminitis. Little research however has been conducted to determine the effects of EMS on routine healthcare of these horses, in particular how they respond to vaccination. It has...
Kim Y, Seo C, Oh S, Kwak J, Jung S, Sin E, Kim H, Ji M, Lee HS, Park HJ, Lee G, Yu J, Kim M, Lee W, Paik MJ.Loxoprofen is a non-steroidal anti-inflammatory drug of the 2-arylpropionic acid type, which has used to treat musculoskeletal disorders in the horse racing industry. However, it has also used illicitly to mask clinical signs of inflammation and pain in racehorses. Thus, its accurate analysis has become an important issue in horse doping laboratories. In this study, an analytical method of loxoprofen was developed as tert-butyldimethylsilyl (TBDMS) derivative by gas chromatography-mass spectrometry (GC-MS). Characteristic fragment ions of [M-15], [M-57], and [M-139] permitted the accurate and ...
Tomlinson JE, Wagner B, Felippe MJB, Van de Walle GR.Immune phenotyping of equine peripheral blood mononuclear cells (PBMC) is commonly described by single or double marker labeling, which limits complex phenotypic descriptions and subpopulation identification. Our objective was to develop a new multispectral flow cytometry protocol to identify and sort equine lymphocyte subpopulations using commercially available, pre-conjugated monoclonal antibodies to cell surface markers. Two clones of anti-equine CD8 (CVS8 and CVS21) were compared in combination with CD3. Clone CVS21 bound non-T CD3 cells in addition to CD8 T cells. Further analysis using c...
Jacob SI, Murray KJ, Rendahl AK, Geor RJ, Schultz NE, McCue ME.Metabolomics, the study of small-molecule metabolites, has increased understanding of human metabolic diseases, but has not been used to study equine metabolic syndrome (EMS). Objective: (1) To examine the serum metabolome of Welsh Ponies with and without insulin dysregulation before and during an oral sugar test (OST). (2) To identify differences in metabolites in ponies with insulin dysregulation, obesity, or history of laminitis. Methods: Twenty Welsh Ponies (mean ± SD; 13.8 ± 9.0 years) classified as non-insulin dysregulated [CON] (n = 10, insulin 60 mU/L) at 75 minutes ...
Lange-Consiglio A, Lazzari B, Perrini C, Pizzi F, Stella A, Cremonesi F, Capra E.Cell-derived microvesicles (MVs) are a recently discovered mechanism of cell-to-cell communication. Our previous data show that MVs secreted by equine amniotic mesenchymal-derived cells (AMCs) are involved in downregulation of proinflammatory genes in lipopolysaccharide-stressed equine tendon and endometrial cells. The aim of the present study was to evaluate whether AMC-MVs contain selected microRNAs (miRNAs) involved in inflammation. Two pools of cells, derived from 3 amniotic membranes each, and their respective MVs were collected. Small RNAs were extracted and deep sequenced, followed by m...
Trachsel DS, Tejada MA, Groesfjeld Christensen V, Pedersen PJ, Kanters JK, Buhl R, Calloe K, Klaerke DA.The long QT syndrome (LQTS) is a channelopathy that can lead to severe arrhythmia and sudden cardiac death. Pharmacologically induced LQTS is caused by interaction between drugs and potassium channels, especially the K 11.1 channel. Due to such interactions, numerous drugs have been withdrawn from the market or are administered with precautions in human medicine. However, some compounds, such as trimethoprim-sulfonamide combinations are still widely used in veterinarian medicine. Therefore, we investigate the effect of trimethoprim-sulfadiazine (TMS), trimethoprim, sulfadiazine, and detomidine...
Naskou MC, Sumner SM, Chocallo A, Kemelmakher H, Thoresen M, Copland I, Galipeau J, Peroni JF.Mesenchymal stem cells (MSCs) produced for clinical purposes rely on culture media containing fetal bovine serum (FBS) which is xenogeneic and has the potential to significantly alter the MSC phenotype, rendering these cells immunogenic. As a result of bovine-derived exogenous proteins expressed on the cell surface, MSCs may be recognized by the host immune system as non-self and be rejected. Platelet lysate (PL) may obviate some of these concerns and shows promising results in human medicine as a possible alternative to FBS. Our goal was to evaluate the use of equine platelet lysate (ePL) poo...
Fedorka CE, Scoggin KE, Boakari YL, Hoppe NE, Squires EL, Ball BA, Troedsson MHT.The deposition of semen into the uterus of the horse induces a transient innate immune response that lasts 24-36 h in the normal mare. There exists a subset of mares that are unable to resolve this inflammation in a timely manner, and are classified as susceptible to the disease of persistent breeding-induced endometritis (PBIE). Lactoferrin is a protein of interest as a potential therapeutic for this persistent inflammation due to its anti-inflammatory and bactericidal properties. The addition of human recombinant lactoferrin (hrLF) to the insemination dose was previously shown to suppress ...
Brandão JS, Alvarenga ML, Pfeifer JPH, Dos Santos VH, Fonseca-Alves CE, Rodrigues M, Laufer-Amorim R, Castillo JAL, Alves ALG.The superficial digital flexor tendon (SDFT) is a structure frequently affected by injuries in high-performance athletic horses, and there are limited therapeutic options. Regenerative medicine has evolved significantly in treating different illnesses. However, understanding the cellular behaviour during mesenchymal stem cell (MSC) transplantation in healthy tissues is not fully known yet. To address the inflammatory response induced by allogeneic MSC transplantation, this study evaluated the local inflammatory response after the application of allogeneic adipose tissue-derived mesenchymal ste...
Rosanowski SM, Chang YM, Stirk AJ, Verheyen KLP.A key focus of the racing industry is to reduce the number of race-day events where horses die suddenly or are euthanased due to catastrophic injury. The objective of this study was therefore to determine risk factors for race-day fatalities in Thoroughbred racehorses, using a cohort of all horses participating in flat racing in Great Britain between 2000 and 2013. Horse-, race- and course-level data were collected and combined with all race-day fatalities, recorded by racecourse veterinarians in a central database. Associations between exposure variables and fatality were assessed using logis...
Anaya G, Fernández ME, Valera M, Molina A, Azcona F, Azor P, Solé M, Moreno-Millán M, Demyda-Peyrás S.Twin foaling is associated with chimaerism in several domestic species and is recognised in horses. In this study, 21,097 purebred Spanish (Pura Raza Español) horse births from the 2015 to 2016 breeding season were investigated for chimaerism. Twin foaled and chimaeric individuals were assessed on the basis of foaling records, short-tandem repeat (STR) parentage test results and a sex-linked STR-based technique. Fourteen twin pregnancies with 23 twin foals born alive were identified (0.066% twin foaling prevalence), including five blood chimaeric cases (21.7%; overall prevalence 0.011%), sugg...
Greay TL, Zahedi A, Krige AS, Owens JM, Rees RL, Ryan UM, Oskam CL, Irwin PJ.Apicomplexan tick-borne pathogens that cause disease in companion animals include species of Babesia Starcovici, 1893, Cytauxzoon Neitz & Thomas, 1948, Hepatozoon Miller, 1908 and Theileria Bettencourt, Franca & Borges, 1907. The only apicomplexan tick-borne disease of companion animals that is known to occur in Australia is babesiosis, caused by Babesia canis vogeli Reichenow, 1937 and Babesia gibsoni Patton, 1910. However, no molecular investigations have widely investigated members of Apicomplexa Levine, 1980 in Australian ticks that parasitise dogs, cats or horses, until this present inves...
Castro Martins M, Peffers MJ, Lee K, Rubio-Martinez LM.Intra-articular administration of stanozolol has shown promising results by improving the clinical management of lameness associated with naturally-occurring osteoarthritis (OA) in horses, and by decreasing osteophyte formation and subchondral bone reaction in sheep following surgically induced OA. However, there is limited evidence on the anti-inflammatory and modulatory properties of stanozolol on articular tissues. The objective of the current study was to evaluate the effects of stanozolol on chondrocyte viability and gene expression in normal equine chondrocytes and an inflammatory in vit...
De Clercq D, Broux B, Vera L, Decloedt A, van Loon G.In human and veterinary medicine, monophasic action potential (MAP) analysis and determination of local refractory periods by contact electrode technique gives valuable information about local cardiac electrophysiological properties. It is used to investigate dysrhythmias and the impact of drugs on the myocardium. Precise measurement of total MAP duration is difficult, therefore the MAP duration is usually determined at a repolarization level of 90% (APD90). Until now, no studies are published about the feasibility of this technique in the standing non-sedated horse. In 6 healthy Warmblood hor...
Zayed M, Adair S, Ursini T, Schumacher J, Misk N, Dhar M.Osteoarthritis (OA), the most common form of joint disease affecting humans and horses, is characterized by the advance and decline of cartilage and loss of function of the affected joint. The progression of OA is steadily accompanied with biochemical events, which interfere with the cytokines and proteolytic enzymes responsible for progress of the disease. Recently, regenerative therapies have been used with an assumption that mesenchymal stem cells (MSCs) possess the potential to prevent the advancement of cartilage damage and potentially regenerate the injured tissue with an ultimate goal o...
Waller A., head of bacteriology at the AHT, describes the causative agent of strangles in horses, and discusses progress with the latest research aimed at improving vaccines against this global disease.
Camacho-Luna P, Buchanan B, Andrews FM.Equine gastric ulcer syndrome (EGUS) primarily describes ulceration in the terminal esophagus, nonglandular squamous mucosa, glandular mucosa of the stomach, and proximal duodenum. EGUS is common in all breeds and ages of horses and foals. This article focuses on the current terminology for EGUS, etiologies and pathogenesis for lesions in the nonglandular and glandular stomach, diagnosis, and a comprehensive approach to the treatment and prevention of EGUS in adult horses and foals.
Cain JL, Jarisch K, Macaluso KR, Luedtke BE.Approximately 700 feral horses, dubbed "trespass horses" by the United States Army, occupy Fort Polk, Louisiana and the surrounding Kisatchie National Forest. These horses are considered a nuisance and hazard, and the military is seeking to remove the horses via adoption. The aim of this research was to evaluate the fecal egg count (FEC), body condition score (BCS), and the presence of Strongylus vulgaris within this previously unstudied horse population prior to removal. The feral horse data was compared to domestic horses living on a single farm in the same area. A modified McMaster FEC, Hen...
Fielding CL.With advances in technology and owner education, field management in equine veterinary medicine continues to evolve. Equine gastrointestinal disease is one of the most common types of emergencies evaluated by equine practitioners, and many of these patients can be effectively managed in the field. Although the equine veterinarian must make numerous decisions, fluid therapy, pain management, and antimicrobial use are 3 of the major choices that must be addressed when initiating field treatment of equine gastrointestinal disease. This article addresses the practical use of these 3 treatment cate...
Tamura N, Kodaira K, Yoshihara E, Mae N, Yamazaki Y, Mita H, Kuroda T, Fukuda K, Tomita A, Kasashima Y.A retrospective cohort study was conducted to investigate risk factors for the failure of Thoroughbred racehorses to return to racing after an injury of the superficial digital flexor tendon (SDFT). Successful return was defined as the completion of five or more races after SDFT injury. The official Japan Racing Association (JRA) medical records of racehorses with a core-type SDFT injury were reviewed for clinical variables related to the characteristics of the horse and the severity of SDFT injuries at the time of diagnosis. Data on racing outcomes were obtained from the official JRA racing d...
Tanaka T, Otoguro T, Yamashita A, Kasai H, Fukuhara T, Matsuura Y, Moriishi K.The 5' untranslated region (UTR) of hepatitis C virus (HCV), which is composed of four domains (I, II, III, and IV) and a pseudoknot, is essential for translation and viral replication. Equine nonprimate hepacivirus (EHcV) harbors a 5' UTR consisting of a large 5'-terminal domain (I); three additional domains (I', II, and III), which are homologous to domains I, II, and III, respectively, of HCV; and a pseudoknot, in the order listed. In this study, we investigated the roles of the EHcV 5' UTR in translation and viral replication. The internal ribosome entry site (IRES) activity of the EHcV 5'...
Bischoff K, Moiseff J.Feed as a cause of poisoning in horses can occur on small or large scales. It is challenging to work up cases of suspected feed contamination, but there are resources available to veterinarians and owners. Feed contamination can be chemical or biological. This article focuses on and provides examples of chemical feed contamination including misformulation, adulteration, and natural contaminants. Additionally, recommendations for feed sampling and diagnostic submission, including legal documentation, are included.
Bosch S, Serra Bragança F, Marin-Perianu M, Marin-Perianu R, van der Zwaag BJ, Voskamp J, Back W, van Weeren R, Havinga P.In this paper, we describe and validate the EquiMoves system, which aims to support equine veterinarians in assessing lameness and gait performance in horses. The system works by capturing horse motion from up to eight synchronized wireless inertial measurement units. It can be used in various equine gait modes, and analyzes both upper-body and limb movements. The validation against an optical motion capture system is based on a Bland-Altman analysis that illustrates the agreement between the two systems. The sagittal kinematic results (protraction, retraction, and sagittal range of motion) sh...
Milinovich GJ, Burrell PC, Pollitt CC, Bouvet A, Trott DJ.Four Gram-positive, catalase-negative, coccoid-shaped isolates were obtained from the caecum and rectum of horses with oligofructose-induced equine laminitis. Phenotypic and phylogenetic studies were performed on these isolates. Initial biochemical profiling assigned two of the isolates to Streptococcus bovis. The other two isolates, however, could not be assigned conclusively on the basis of their biochemical profiles. Gene sequence analysis demonstrated that the four new isolates were related most closely to Streptococcus suis based on the 16S rRNA gene and to Streptococcus orisratti based o...
Ragno VM, Zello GA, Klein CD, Montgomery JB.Obesity data in people and companion animals are depicting a future of increasing morbidity, cost for society, and significant health and welfare concerns. Between 25 and 50% of cats, dogs, and horses in developed countries are overweight or obese, which mirrors the situation in humans. Equine metabolic syndrome (EMS) was named after human metabolic syndrome (MetS), which has about 30 years of lead in research efforts. Even though the complications of the two syndromes seem to grossly differ (cardiac vs. laminitis risk), a number of similar disease mechanisms are worthy of investigation. Sinc...
Ikhuoso OA, Monroy JC, Rivas-Caceres RR, Cipriano-Salazar M, Barbabosa Pliego A.Although the strangles disease of Streptococcus equi was discovered many decades ago in 1,251 by Jordanus Ruffus, it has still remained a major frequently diagnosed infection in horses all over the world. The S. equi subspecies pathogen is known to be often resistant to antibiotic treatment, and it makes the antibiotics inefficient; hence, this review was conducted to study how the disease can be managed. The age-long sign of this infection is the oozing of pus through the mucous and skin membranes. Affected horses lose appetite, develop fever, and become depressed, which result in them losin...
Bullone M, Moran K, Lavoie-Lamoureux A, Lavoie JP.Neutrophils accumulate in the airways of horses with heaves. They likely play an important role in the disease pathogenesis. Understanding the pathways regulating their migration may help identifying new therapeutic targets. Objective: MAPK and PI3K pathways are involved in neutrophil migration toward the airway lumen in heaves. Methods: Twelve heaves-affected horses and 4 healthy horses. Methods: Migratory activity of bronchoalveolar lavage fluids (BALF) from horses with heaves and healthy horses was compared by means of a Boyden chamber. Involvement of MAPK and PI3K pathways in neutrophil mi...
Stewart JM, Blakely JA, Johnson MD.Non-covalent modification of cytochrome c may have implications for electron transport and energy metabolism. We examined the interaction of various fatty acids (FAs), their coenzyme A and carnitine esters, and fatty alcohols with horse heart ferrocytochrome c. A comparison of FAs indicated a minimum chain length of 14 carbons was required for significant effect on the ferroheme chromophore and major changes in electronic spectra. Coenzyme A and carnitine esters interacted less strongly than FAs whereas long-chain alcohols did not interact with the protein. We found a single, saturable FA bind...
Brama PA, TeKoppele JM, Beekman B, van El B, Barneveld A, van Weeren PR.To investigate the role of stromelysin (MMP-3) activity in synovial fluid (SF) at different stages of development and in common joint disorders in the horse. Methods: Stromelysin activity was determined with a fluorogenic enzyme activity assay in SF of normal joints of fetal, juvenile and adult horses, and in SF of horses suffering from the developmental orthopaedic disease osteochondrosis (OC) or osteoarthritis (OA). Additionally, MMP-3 activity was expressed as a ratio of previously reported general MMP activity in the same SF samples. Results: The levels of active stromelysin were 30-fold t...
Gornik K, Moore P, Figueiredo M, Vandenplas M.Human corneal cells have detectable levels of TLRs 1-10. TLRs 2 and 4 are the major corneal receptors, recognizing the PAMPs associated with fungal invasion in humans. The conjunctiva and limbus contain TLRs 2, 4, and 9. Our purpose was to determine the expression of TLRs 2, 3, 4, 6, 9, and MD-2 in the normal equine cornea, conjunctiva, and limbus. Methods: Corneal, limbal, and conjunctival tissues were collected from seven euthanized horses having no evidence of ocular disease. RNA extraction with DNase-1 digestion was performed followed by RT-PCR to determine expression of TLRs 2, 3, 4, 6, 9...
Betbeze CM, Wu CC, Krohne SG, Stiles J.To evaluate the in vitro antifungal properties of silver sulfadiazine (SSD) and natamycin against filamentous fungi isolated from eyes of horses with keratomycosis. Methods: Filamentous fungal isolates obtained from eyes of keratomycosis-affected horses. Methods: Fungal culture of ocular samples yielded 6 Fusarium spp; 7 Aspergillus spp; and 1 isolate each of Curvularia, Scopulariopsis, Penicillium, and Chrysosporium. For each fungal isolate, minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of SSD and natamycin were determined. Results: For all 17 fungal isolat...
Rhodes DM, Magdesian KG, Byrne BA, Kass PH, Edman J, Spier SJ.Few studies report the minimum inhibitory concentrations for antimicrobials against equine Corynebacterium pseudotuberculosis isolates. Objective: To evaluate trends in the in vitro activities of 20 antimicrobials against equine Corynebacterium pseudotuberculosis isolates from 1996 to 2012 and to determine if a relationship exists between the minimum inhibitory concentration (MIC) and location of the abscess. Methods: Corynebacterium pseudotuberculosis isolates from 196 horses with naturally occurring disease. Methods: Retrospective and cross-sectional design. Medical records were reviewed to ...
Davidson TR, Chamberlain CS, Bridges TS, Spicer LJ.Little is known regarding the hormonal regulation of granulosa cell steroidogenesis and the ovarian insulin-like growth factor (IGF) system in the mare. The objectives of this study were to determine, first, if estradiol, insulin, and/or FSH affect steroid production by equine granulosa cells (experiment 1) and, second, if the components of the IGF system are produced by equine granulosa cells in culture as well as whether estradiol, insulin, and/or FSH affects IGF and/or IGF-binding protein (IGFBP) production by equine granulosa cells (experiment 2). Granulosa cells from small (6-15 mm), medi...
Cullen CL, Grahn BH.The prevalence of equine glaucoma seen by the ophthalmology service at the Western College of Veterinary Medicine (WCVM) was 6.5%. The majority of cases (11/13) were associated with clinical manifestations of uveitis. Congenital glaucoma was documented in 1 case, and primary glaucoma was diagnosed in a 12-year-old quarter horse. There were no breed or sex predilections evident. Affected horses were middle-aged to old (average age = 9.5 years, ranging from 2 weeks to 23 years). The clinical manifestations of equine glaucoma included blindness, diffuse corneal edema, corneal vascularization, bup...
Tyson F, Dalesman S, Brophy PM, Morphew RM.Faecal egg counts (FECs) are the standard method of diagnosing the level of parasitic helminth egg shedding in horses and other grazing animals. Testing before treatment is an important factor in slowing the appearance of anthelmintic resistance in nematode parasites. The FECPAK, optimised for livestock, is reported to allow owners to perform FECs on their own animals without the need for a separate microscope or any specialist knowledge by tapping into remote expertise. However, the performance of the FECPAK has yet to be assessed for equids. Therefore, a comparison of the FECPAK (G2) method ...
Elarbi MM, Ragle CA, Fransson BA, Farnsworth KD.OBJECTIVE To develop and validate a simulation model for laparoscopic ovariectomy in standing horses. DESIGN Prospective cohort study. SAMPLE 15 third-year veterinary students and 4 equine surgeons with experience in laparoscopy. PROCEDURES A simulation model that mimicked laparoscopic ovariectomy in standing horses was developed. Face validity of the model was determined with a questionnaire completed by the equine surgeons. Construct validity was determined by comparing performance scores (based on time to completion and accuracy completing various operative tasks) for simulated laparoscopic...
Suagee JK, Corl BA, Crisman MV, Hulver MW, McCutcheon LJ, Geor RJ.Laminitis is a painful, inflammatory disease of the equine hoof that often results in euthanasia. Elevated plasma insulin concentrations are a predictive factor for laminitis, and in previously healthy horses and ponies, laminitis was induced by infusion of insulin. Thus, we chose to determine if an infusion of insulin would increase plasma concentrations of inflammatory cytokines and cytokine mRNA abundance in subcutaneous adipose tissue, skeletal muscle, and white blood cells. Ten mature Thoroughbred mares received an insulin infusion that elevated plasma insulin concentrations for 6h or an ...
Hackett RP, Ducharme NG, Fubini SL, Erb HN.Videorecordings of the laryngeal activity of 108 unsedated horses were obtained at rest by passing a flexible videoendoscope into the nasopharynx through the right ventral meatus. All videotaped images were reviewed once, and 72 were reviewed twice, by three veterinarians. Laryngeal cartilage movement was assessed subjectively with a five-tier grading system. The mean intraobserver agreement was 83.3% (range, 75.0%-90.2%) with a kappa statistic of .65 to .98. The mean interobserver agreement was 79.0% (range, 70.4%-80.6%) with a kappa statistic of .51 to .90. A computer program was developed t...
Prescott JF.Current understanding of the epidemiology of Rhodococcus equi infection on horse farms is reviewed. Infection is widespread in herbivores and their environment, because herbivore manure supplies the simple organic acid substrates on which the organism thrives. There is a progressive development of infection in the soil on horse farms with prolonged use, because: (1) there is a continual supply of nutrients; (2) the organism multiplies progressively as temperatures rise; (3) the bacterium has a robust nature. While this aerobic organism fails to multiply in the largely anaerobic intestine of th...
Mesquita LP, Arévalo AF, Zanatto DA, Miyashiro SI, Cunha EMS, de Souza MDCC, Villalobos EMC, Mori CMC, Maiorka PC, Mori E.The equine herpesvirus type 1 (EHV-1) is an important cause of myeloencephalopathy and respiratory disease in horses. Animal models for EHV-1 infection have been specially developed using mice and Syrian hamsters (Mesocricetus auratus). However, few studies have attempted to evaluate the pathogenesis of EHV-1 infection in the central nervous system (CNS) and respiratory system of hamsters. Therefore, the aim of this study was to evaluate the pathogenesis of four Brazilian EHV-1 strains within the CNS and lungs of Syrian hamsters. Hamsters intranasally infected with A4/72, A9/92, A3/97, and Iso...
Bonin SJ, Clayton HM, Lanovaz JL, Johnson TJ.To develop a method of measuring 3-dimensional kinematics of the temporomandibular joint (TMJ) in horses chewing sweet feed. Methods: 4 mature horses that had good dental health. Methods: Markers attached to the skin over the skull and mandible were tracked by an optical tracking system. Movements of the mandible relative to the skull were described in terms of 3 rotations and 3 translations. A virtual marker was created on the midline between the rami of the mandibles at the level of the rostral end of the facial crest to facilitate observation of mandibular movements. Results: During the ope...
Schwartz AJ, Wilson DA, Keegan KG, Ganjam VK, Sun Y, Weber KT, Zhang J.To determine significant molecular and cellular factors responsible for differences in second-intention healing in thoracic and metacarpal wounds of horses. Methods: 6 adult mixed-breed horses. Methods: A full-thickness skin wound on the metacarpus and another such wound on the pectoral region were created, photographed, and measured, and tissue was harvested from these sites weekly for 4 weeks. Gene expression of type-I collagen, transforming growth factor (TGF)-beta1, matrix metalloproteinase (MMP)-1, and tissue inhibitor of metalloproteinase (TIMP)-1 were determined by quantitative in situ ...
Lincoln VJ, Page PC, Kopp C, Mathis A, von Niederhäusern R, Burger D, Herholz C.Species belonging to the Culicoides complexes (Diptera, Ceratopogonidae), obsoletus and pulicaris, in Switzerland, are potential vectors of both bluetongue virus (BTV) and African horse sickness virus (AHSV). The epidemic of BTV in 2006 and 2007 in Europe has highlighted the risk of introduction and spread of vector-borne diseases in previously non-endemic areas. As a measure of prevention, as part of an integrated control programme in the event of an outbreak of African horse sickness (AHS), it is of utmost importance to prevent, or substantially reduce, contact between horses and Culicoides....
McFarlane D, Hale GM, Johnson EM, Maxwell LK.To determine effects of pituitary pars intermedia dysfunction (Cushing's disease) and age on fecal egg count and time to egg reappearance after anthelmintic treatment in horses residing in similar environments. Methods: Cross-sectional study. Methods: 29 healthy horses (4 to 35 years old) and 13 horses with PPID (13 to 33 years old). Methods: Fecal egg counts were performed by use of a modified Wisconsin flotation method at 2-week intervals before and after ivermectin treatment. Results: Horses with PPID had higher fecal egg counts before and 8, 10, and 12 weeks after ivermectin treatment, com...
Osteochondrosis (OC) develops in growing horses due to disturbed differentiation and maturation of cartilage, particularly at the predilection sites of the fetlock, hock and stifle joints. Horses with osteochondrotic lesions are at a high risk of developing orthopaedic problems later in life. This article briefly reviews the published heritability estimates for OC and offers perspectives for selection in the horse industry. Heritabilities for OC in Warmblood and Standardbred horses have been estimated at 0.1-0.4 in animal threshold models. Whole genome scans using microsatellites have identifi...
Oliveira FAS, Castro RJS, de Oliveira JF, Barreto FM, Farias MPO, Marinho GLOC, Soares MJDS, Silva-Júnior A, Schwarz DGG.In Brazil, the horse is frequently used in cultural activities, sports, and in rural and urban work, implementing the economy in different social classes. Among the diseases in horses with zoonotic potential, rabies has been neglected in the country, increasing the risk of spreading the disease across borders. The present study evaluated the spatiotemporal distribution and temporal trend of rabies in horses in Brazil between 2010 and 2019. During this period, 1290 cases of rabies were detected in horses in Brazil, mainly in the states of São Paulo (21.7%) and Mato Grosso (13.3%). However, Esp...
To document morphologic changes that occur in equine intestinal serosa after experimentally induced ischemia and subsequent reperfusion (jejunum, ascending colon) or after intraluminal distention and decompression (jejunum). Methods: Morphologic effects of ischemia-reperfusion or intraluminal distention-decompression determined on the serosal layer of the equine jejunum. The large colon serosa was evaluated after ischemia-reperfusion injury. Methods: Seven adult horses. Methods: After induction of general anesthesia and ventral median celiotomy, ischemia was created by arteriovenous (AVO) and ...
Bhoora R, Buss P, Guthrie AJ, Penzhorn BL, Collins NE.Seventy EDTA blood samples collected from plains zebra (Equus quagga burchellii) and Cape mountain zebra (Equus zebra zebra) were screened for the presence of piroplasm parasite DNA using quantitative T. equi-specific and B. caballi-specific TaqMan real-time PCR (qPCR) tests. T. equi parasite DNA was detected in 60 samples, 19 of which were also positive for B. caballi. Approximately 1480bp of the piroplasm 18S rRNA gene was amplified and sequenced from 17 samples, while the V4 hypervariable region of the 18S rRNA gene was amplified, cloned and sequenced from 31 samples. BLASTN analysis reveal...
Bartholomew S, Owens SD, Ferraro GL, Carrade DD, Lara DJ, Librach FA, Borjesson DL, Galuppo LD.Stem cells derived from umbilical cord tissue (UCT) and umbilical cord blood (UCB) in human subjects and horses can be obtained in a minimally invasive fashion with successful propagation of mesenchymal stem cells (MSCs). Currently there are no detailed protocols documenting a procedure to harvest UCB and UCT safely for equine stem cell propagation. Objective: UCB and UCT could be collected without harm to mare or foal. Objective: To develop a standard and safe method for UCB and UCT collection, and prospectively to compare foal and mare health between groups of animals where tissue was and wa...
De Clercq D, van Loon G, Baert K, Tavernier R, Croubels S, De Backer P, Deprez P.Six horses without underlying cardiac disease were presented because of atrial fibrillation of between 5 and 12 months duration. These horses received an intravenous amiodarone treatment of 5mg/kg/h for 1 h followed by 0.83mg/kg/h for 23h and subsequently 1.9mg/kg/h for 30h. During treatment, clinical signs were monitored and a surface ECG and an intra-atrial electrogram were recorded. Infusion was discontinued when sinus rhythm or side effects occurred. Four horses successfully cardioverted, of which one showed symptoms of hind limb weakness and weight shifting. Two horses did not cardiovert ...
Leise BS, Watts MR, Roy S, Yilmaz AS, Alder H, Belknap JK.Dysadhesion of laminar basal epithelial cells (LBECs) from the underlying dermis is the central event leading to structural failure in equine laminitis. Although many studies of sepsis-related laminitis have reported multiple events occurring throughout the lamellar tissue, there is minimal information regarding signalling events occurring specifically in LBECs. Objective: To determine signalling events in the LBECs during the early stages of carbohydrate-induced laminitis. Methods: Experimental study. Methods: Eight horses were given an overload of carbohydrate (CHO) consisting of corn starch...
Lazary S, Marti E, Szalai G, Gaillard C, Gerber H.The equine leucocyte antigen (ELA) types and the clinical diagnosis for equine sarcoid and summer dermatitis were evaluated in 2026 horses representing five breeds. Data were analysed in unrelated animals and in family material. In the case of equine sarcoid, a strong association was observed between the ELA class II DW13 antigen and its effect on Swiss (cP < 0.001), French (cP < 0.0001) and Irish (cP < 0.01) Warmblood horses. The class I antigen A3 occurred more frequently in sarcoid-affected French horses (cP < 0.001). These results confirm our earlier findings (Gerber et al. 1988). Among Fr...
Matthee S, Dreyer FH, Hoffmann WA, van Niekerk FE.Fifty-one per cent of 110 questionnaires, designed for obtaining information on helminth control practices and management on Thoroughbred stud farms in South Africa, were completed by farmers during 2000. The number of horses per farm included in the questionnaire survey ranged from 15 to 410. Foals, yearlings and adult horses were treated with anthelmintics at a mean of 7.3 +/- 3.0, 6.6 +/- 2.7 and 5.3 +/- 2.3 times per year, respectively. An average of 3.4 different drugs were used annually, with ivermectin being used bymost farmers during 1997-2000. On 43% of farms the weights of horses wer...
