Infections in horses encompass a range of diseases caused by various pathogens, including bacteria, viruses, fungi, and parasites. These infections can affect different systems within the horse, such as the respiratory, gastrointestinal, and integumentary systems, leading to a variety of clinical signs depending on the pathogen and the severity of the infection. Common infectious diseases in horses include equine influenza, strangles, and equine herpesvirus. Diagnosis often involves clinical examination, laboratory testing, and sometimes imaging, to identify the causative agent and assess the extent of the disease. Treatment strategies may include antimicrobial therapy, supportive care, and preventive measures such as vaccination and biosecurity practices. This page aggregates peer-reviewed research studies and scholarly articles that explore the pathogenesis, diagnosis, treatment, and prevention of infectious diseases in equine populations.
Cuming RS, Abarca EM, Duran S, Wooldridge AA, Stewart AJ, Ravis W, Babu RJ, Lin YJ, Hathcock T.To determine in vitro release profiles, transcorneal permeation, and ocular injection characteristics of a voriconazole-containing thermogel suitable for injection into the subconjunctival space (SCS). In vitro release rate of voriconazole (0.3% and 1.5%) from poly (DL-lactide-co-glycolide-b-ethylene glycol-b-DL-lactide-co-glycolide) (PLGA-PEG-PLGA) thermogel was determined for 28 days. A Franz cell diffusion chamber was used to evaluate equine transcorneal and transscleral permeation of voriconazole (1.5% topical solution, 0.3% and 1.5% voriconazole-thermogel) for 24 hours. Antifungal activit...
Murphy B, Bell C, Koehne A, Dubielzig RR.Odontoameloblastoma (OA) is a mixed odontogenic tumor that is an ameloblastoma with concurrent histologic evidence of odontoma differentiation. As a mixed tumor, OA is a tripartite lesion comprised of neoplastic odontogenic epithelium, induced dental ectomesenchyme (dental pulp), and mineralized dental matrix. Although rare, OA represents a diagnostic conundrum, as it is histologically closely related to 2 other mixed odontogenic tumors: odontoma (complex and compound) and ameloblastic fibro-odontoma. Herein we describe an OA arising from the mandible of a 4-mo-old Fischer 344 rat that had bee...
Parkinson NJ, Buechner-Maxwell VA, Witonsky SG, Pleasant RS, Werre SR, Ahmed SA.The innate immune response to lipopolysaccharide contributes substantially to the morbidity and mortality of gram-negative sepsis. Horses and humans share an exquisite sensitivity to lipopolysaccharide and thus the horse may provide valuable comparative insights into this aspect of the inflammatory response. MicroRNAs, small non-coding RNA molecules acting as post-transcriptional regulators of gene expression, have key roles in toll-like receptor signaling regulation but have not been studied in this context in horses. The central hypothesis of this study was that lipopolysaccharide induces di...
Alanazi AD, Mukbel RM, Alyousif MS, AlShehri ZS, Alanazi IO, Al-Mohammed HI.In the last decade, Parascaris spp. resistance to anthelmintics has been recorded in many countries. In Saudi Arabia, there are limited data available on Parascaris spp. resistance to anthelmintics. Objective: To determine the current status of ivermectin, abamectin and praziquantel combined, and fenbendazole resistance to Parascaris spp. in horses in Saudi Arabia. Methods: Three hundred and forty-one foals from eleven different farms were examined by faecal egg count (FEC). The foals were all Arab horses aged 17.2 ± 4.5 (SD) months. Ivermectin (n = 46 foals), abamectin and praziquantel combi...
Mahne AT, Janse van Rensburg D, Hewetson M.A 4-year-old Thoroughbred gelding underwent an explorative celiotomy for a suspected small intestinal obstruction. During surgery, an impacted diverticulum of the ileum was suspected, necessitating a jejunocaecostomy. The owner opted for euthanasia. On post-mortem examination and histopathology, a true diverticulum on the mesenteric side of the ileum, with ileal hypertrophy, was diagnosed.
Collas C, Sallé G, Dumont B, Cabaret J, Cortet J, Martin-Rosset W, Wimel L, Fleurance G.The spread of anthelmintic resistance in equine strongyle nematodes has become a major problem, advocating for the development of alternative control for strongyles. Our study consisted of both in vivo and in vitro experiments. We investigate for the first time the efficacy of a short-term consumption of tannin-rich sainfoin (Onobrychis viciifolia) or extra proteins in naturally infected horses. We used 30 horses allocated into three groups of 10 individuals that received for 18 days either (i) a tannin-rich diet with 70% DM sainfoin pellets (Sd), (ii) a protein-rich diet with 52% DM Italian r...
Haltmayer E, Schwendenwein I, Licka TF.Injuries penetrating synovial structures are common in equine practice and often result in septic synovitis. Significantly increased plasma levels of serum amyloid A (SAA) have been found in various infectious conditions in horses including wounds and septic arthritis. Plasma SAA levels were found to decrease rapidly once the infectious stimulus was eliminated. The purpose of the current study was to investigate the usefulness of serial measurements of plasma SAA as a monitoring tool for the response to treatment of horses presented with injuries penetrating synovial structures. In the current...
Tallmadge RL, Miller SC, Parry SA, Felippe MJB.The value of prophylactic neonatal vaccination is challenged by the interference of passively transferred maternal antibodies and immune competence at birth. Taken our previous studies on equine B cell ontogeny, we hypothesized that the equine neonate generates a diverse immunoglobulin repertoire in response to vaccination, independently of circulating maternal antibodies. In this study, equine neonates were vaccinated with 3 doses of keyhole limpet hemocyanin (KLH) or equine influenza vaccine, and humoral immune responses were assessed using antigen-specific serum antibodies and B cell Ig var...
Mirajkar NS, Kelley MR, Gebhart CJ.Reported herein is the draft genome sequence of equine-origin Lawsonia intracellularis strain E40504, an obligate intracellular bacterium and the etiological agent of equine proliferative enteropathy. The 1.69-Mb draft genome sequence includes 1,380 protein-coding genes and 49 RNA genes, and it lacks a genomic island reported in swine-origin L. intracellularis strain PHE/MN1-00.
Adler DMT, Damborg P, Verwilghen DR.Lameness is the most commonly reported health problem in horses, and lameness investigations which include local anaesthetic injections are routinely performed by equine practitioners. Through this process, bacteria can enter the tissues perforated by the needle and may cause local infections at the injection site. The objective of this in vitro study was to investigate if local anaesthetics at concentrations available in commercially available solutions could inhibit growth and/or kill bacteria that could be inoculated into the synovial space or soft tissues during injection. This study evalu...
Gutiérrez-Expósito D, García-Bocanegra I, Howe DK, Arenas-Montes A, Yeargan MR, Ness SL, Ortega-Mora LM, Álvarez-García G.Equine besnoitiosis, caused by Besnoitia bennetti, and equine protozoal myeloencephalitis (EPM), caused by Sarcocystis neurona and Neospora hughesi are relevant equine diseases in the Americas that have been scarcely studied in Europe. Thus, a serosurvey of these cystogenic coccidia was carried out in Southern Spain. A cross-sectional study was performed and serum samples from horses (n = 553), donkeys (n = 85) and mules (n = 83) were included. An in-house enzyme-linked immunosorbent assay (ELISA) was employed to identify a Besnoitia spp. infection and positive results were confirmed by ...
Barrell EA, Asakawa MG, Felippe MJB, Divers TJ, Stokol T.Acute leukemia is rare in horses. Herein we describe historical, clinicopathologic, and postmortem findings in 6 horses with acute leukemia. Medical records of horses with >20% bone marrow blasts and cytochemical or immunophenotyping results were reviewed. Affected horses were 2-8 y of age and of different breeds and sex. Horses were presented acutely with nonspecific signs (e.g., fever, lethargy). Characteristic hemogram findings were bi- or pancytopenia with low blast numbers. Histologic examination revealed extramedullary infiltrates, especially in lymph nodes, spleen, kidney, liver, and lu...
Guérin F, Fines-Guyon M, Meignen P, Delente G, Fondrinier C, Bourdon N, Cattoir V, Léon A.The epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) isolated in horse infections is not well documented, especially in France. The aim of the study was to evaluate the prevalence of MRSA isolates in horse infections from 2007 to 2013 in France and to characterize phenotypically and genotypically this collection. Out of 1393 S. aureus horse isolates, 85 (6.1%) were confirmed to be MRSA. Interestingly, the prevalence of MRSA significantly increased from 2007-2009 to 2010-2013 (0.7 vs. 9.5%, P <0.0001). Resistance to methicillin was due to the presence of the mecA gene in 84 st...
Sykora S, Jindra C, Hofer M, Steinborn R, Brandt S.In horses, squamous cell carcinomas (SCC) commonly affect the external genitals. There is growing evidence that equine papillomavirus type 2 (EcPV2) infection promotes disease development. To assess the possible association of EcPV2 with equine SCCs of the head (HSCC), 15 HSCC DNA samples were screened by E6/E7, E2, and LCR PCR and amplicons were analysed for sequence variations. The physical form of EcPV2 in HSCC, genital lesions, and smegma from horses with SCC was then addressed using EcPV2 immunocapture PCR (IC/PCR) for detection of virion, and E6 vs. E2 qPCR to investigate possible integr...
Equine lentivirus receptor-1 (ELR1) has been characterized as the specific functional receptor that mediates equine infectious anemia virus (EIAV) entrance to horse macrophages. This receptor is tumor necrosis factor receptor superfamily member 14 (TNFRSF14). The aim of this study was to investigate the occurrence of allelic variants in the coding sequence of equine TNFRSF14 gene by screening for single-nucleotide polymorphisms (SNPs) in different equine populations. Forty seven horse samples were randomly selected from a reservoir of EIAV-seropositive and seronegative samples collected from d...
Mani RJ, Thachil AJ, Ramachandran A.Accurate and timely identification of infectious etiologies is of great significance in veterinary microbiology, especially for critical diseases such as strangles, a highly contagious disease of horses caused by Streptococcus equi subsp. equi. We evaluated a matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) platform for use in species- and subspecies-level identification of S. equi isolates from horses and compared it with an automated biochemical system. We used 25 clinical isolates each of S. equi subsp. equi and S. equi subsp. zooepidemicus. Using ...
Southwood LL, Lindborg S, Myers M, Aceto HW.To compare long-term outcome of Salmonella-positive versus Salmonella-negative horses discharged from hospital after colic surgery. Methods: Retrospective case-control. Methods: Horses discharged from the hospital after colic surgery. For each horse with positive culture for Salmonella enterica (SAL-POS, n = 59), at least 2 horses testing negative for S. enterica (SAL-NEG, n = 119) were enrolled. Methods: Owners were interviewed via phone at least 12 months after surgery regarding: (1) complications after discharge from the hospital; (2) duration of survival; and (3) return to prior or...
Harmon CCG, Hawkins JF, Li J, Connell S, Miller M, Saenger M, Freeman LJ.OBJECTIVE To determine the effects of 3 topically applied treatments (1% silver sulfadiazine cream [SSC], triple antimicrobial ointment [TAO], and hyperosmolar nanoemulsion [HNE]) on microbial counts, exuberant granulation tissue (EGT) development, and reepithelialization of contaminated wounds at the distal aspect of the limbs of horses. ANIMALS 8 healthy adult horses. PROCEDURES A 2.5 × 2.5-cm, full-thickness, cutaneous wound was created at the dorsal aspect of each metacarpus and metatarsus (1 wound/limb/horse), covered with nonadhesive dressing, and bandaged. Wounds were inoculated with b...
Zarski LM, High EA, Nelli RK, Bolin SR, Williams KJ, Hussey G.Equine herpesvirus 5 (EHV-5) infection is associated with pulmonary fibrosis in horses, but further studies on EHV-5 persistence in equine cells are needed to fully understand viral and host contributions to disease pathogenesis. Our aim was to develop a quantitative PCR (qPCR) assay to measure EHV-5 viral copy number in equine cell cultures, blood lymphocytes, and nasal swabs of horses. Furthermore, we used a recently developed equine primary respiratory cell culture system to study EHV-5 pathogenesis at the respiratory tract. PCR primers and a probe were designed to target gene E11 of the EH...
Gizaw Y, Megersa M, Fayera T.Dourine is a venereal transmitted trypanosomosis causing a major health problem threatening equines worldwide. The origin and identification of Trypanosoma equiperdum within the subgenus Trypanozoon is still a subject of debate. Unlike other trypanosomal infections, dourine is transmitted almost exclusively by coitus. Diagnosis of dourine has continued to be a challenge, due to limited knowledge about the parasite and host-parasite interaction following infection. The pathological lesions caused by the diseases are poorly described and are observed mainly in the reproductive organs, in the ner...
Dayaram A, Franz M, Schattschneider A, Damiani AM, Bischofberger S, Osterrieder N, Greenwood AD.For viruses to utilize environmental vectors (hard surfaces, soil, water) for transmission, physical and chemical stability is a prerequisite. There are many factors including pH, salinity, temperature, and turbidity that are known to contribute to the ability of viruses to persist in water. Equine herpesvirus type-1 (EHV-1) is a pathogenic alphaherpesvirus associated with domestic horses and wild equids. EHV-1 and recombinants of EHV-1 and EHV-9 are able to cause infections in non-equid animal species, particularly in captive settings. Many of the captive non-equid mammals are not naturally s...
Saputra S, Jordan D, Worthing KA, Norris JM, Wong HS, Abraham R, Trott DJ, Abraham S.Methicillin-resistant coagulase-positive staphylococci (CoPS) have become increasingly recognised as opportunistic pathogens that limit therapeutic options in companion animals. The frequency of methicillin resistance amongst clinical isolates on an Australia-wide level is unknown. This study determined antimicrobial susceptibility patterns for CoPS isolated from clinical infections in companion animals (dogs, cats and horses) as part of the first nation-wide survey on antimicrobial resistance in animal pathogens in Australia for a one-year period (January 2013 to January 2014). Clinical Staph...
Rutenberg D, Venner M, Giguère S.There is conflicting data regarding the efficacy of tulathromycin for the treatment of foals with bronchopneumonia. Tulathromycin is effective for the treatment of bronchopneumonia in foals and noninferior to the combination of azithromycin and rifampin. A total of 240 foals on a farm endemic for infections caused by Rhodococcus equi. In a controlled, randomized, and double-blinded clinical trial, foals with ultrasonographic pulmonary lesions (abscess score 10-15 cm) were allocated to 3 groups: 1-tulathromycin IM q 7 days (n = 80); 2-azithromycin-rifampin, orally q24h (n = 80); or 3-untreated ...
Brilhante RSN, Bittencourt PV, de Souza Collares Castelo-Branco D, de Melo Guedes GM, de Oliveira JS, Alencar LP, de Aguiar Cordeiro R, Pinheiro M....This study aimed to assess the biofilm-forming ability of Candida spp. from the ocular conjunctiva of horses and to investigate the antifungal susceptibility of these biofilms. Methods: Initially, the biofilm-forming ability of 15 strains was assessed by crystal violet staining, which reveals the fungal biomass adhered to the polystyrene plates, and scanning electron microscopy. Then, the minimum inhibitory concentrations (MICs) of amphotericin B, fluconazole, itraconazole, and caspofungin were initially determined against strains in planktonic form. Afterward, antifungal susceptibility of mat...
ELISAs are known to have a higher diagnostic sensitivity than the agar gel immunodiffusion (AGID) when employed for serological diagnosis of equine infectious anaemia (EIA). For this purpose, an "in-house" and five commercial ELISAs available in Italy were assessed by the National Reference Centre for EIA for their analytic specificity (Sp); precocity, defined as capability of detecting first antibodies produced during a new infection; precision based on repeatability and reproducibility, estimated from the coefficient of variation (CV); accuracy, estimated from multiple K and relative Sp and ...
Suganuma K, Yamasaki S, Molefe NI, Musinguzi PS, Davaasuren B, Mossaad E, Narantsatsral S, Battur B, Battsetseg B, Inoue N.Dourine is caused by Trypanosoma equiperdum via coitus with an infected horse. Although dourine is distributed in Equidae worldwide and is listed as an internationally important animal disease by the World Organization for Animal Health (OIE), no effective treatment strategies have been established. In addition, there are no reports on drug discovery, because no drug screening system exists for this parasite. A new T. equiperdum strain was recently isolated from the genital organ of a stallion that showed typical symptoms of dourine. In the present study, we adapted T. equiperdum IVM-t1 from...
Cymerys J, Słońska A, Tucholska A, Golke A, Chmielewska A, Bańbura MW.Equine herpesvirus 1 (EHV-1), like other members of the Alphaherpesvirinae subfamily, is a neurotropic virus causing latent infections in the nervous system of the natural host. In the present study, we have investigated EHV-1 replication (wild-type Jan-E strain and Rac-H laboratory strain) during long-term infection and during the passages of the virus in cultured neurons. The studies were performed on primary murine neurons, which are an excellent in vitro model for studying neurotropism and neurovirulence of EHV-1. Using real-time cell growth analysis, we have demonstrated for the first tim...
Becker E, Venter GJ, Greyling T, Molini U, van Hamburg H.Equine mortalities suspected to be due to African horse sickness (AHS) were reported from the arid Khomas Region, Namibia, in 2008. The area was previously considered a localized AHS-free area. Hartmann's mountain zebra (Equus zebra hartmannae), a potential but unconfirmed reservoir host of African horse sickness virus (AHSV), occurs in the region. Between 2009 and 2010 serum, blood and tissue samples from 31 culled E. z. hartmannae were analysed by reverse transcription-polymerase chain reaction (RT-PCR) (n = 31) and enzyme-linked immunosorbent assay (ELISA) (n = 18) to determine the p...
Worku Y, Wondimagegn W, Aklilu N, Assefa Z, Gizachew A.A prospective study was conducted to describe clinical epidemiology of equine colic in the Society for Protection of Animal Abroad and Donkey Sanctuary Project Clinic, at Debre Zeit, Ethiopia, from November 2014 to April 2015. The objectives were to describe clinical epidemiology of equine colic, to characterize the main types of equine colic, and to determine the major risk factors associated with equine colic. The method which was used in the study was attending clinical case of equine and assessing physiological parameters, fecal egg count, abdominal sounds, and rectal examination as well a...
Hodgkinson JE, Lichtenfels JR, Mair TS, Cripps P, Freeman KL, Ramsey YH, Love S, Matthews JB.We report the use of six oligoprobes designed from intergenic spacer region sequences to identify fourth-stage larvae (L4) of the tribe Cyathostominae. Oligoprobes were designed for identification of the following species: Cylicocyclus ashworthi, Cylicocyclus nassatus, Cylicocyclus insigne, Cyathostomum catinatum, Cylicostephanus goldi, and Cylicostephanus longibursatus. A seventh probe was designed as a positive control to identify all these members of the Cyathostominae. The intergenic spacer region was amplified by PCR using conserved primers. Initially, three oligoprobes were used in South...
Barba M, Stewart AJ, Passler T, Wooldridge AA, van Santen E, Chamorro MF, Cattley RC, Hathcock T, Hogsette JA, Hu XP.The route of Corynebacterium pseudotuberculosis infection in horses remains undetermined, but transmission by insects is suspected. Objective: To investigate house flies (Musca domestica L.) as vectors of C. pseudotuberculosis transmission in horses. Methods: Eight healthy, adult ponies. Methods: Randomized, controlled, blinded prospective study. Ten wounds were created in the pectoral region where cages for flies were attached. Three ponies were directly inoculated with C. pseudotuberculosis. Four ponies were exposed for 24 hours to 20 hours C. pseudotuberculosis-inoculated flies. One negativ...
Bruhn O, Regenhard P, Michalek M, Paul S, Gelhaus C, Jung S, Thaller G, Podschun R, Leippe M, Grötzinger J, Kalm E.Defensins are a predominant class of antimicrobial peptides, which act as endogenous antibiotics. Defensins are classified into three distinct sub-families: theta-, beta-, and alpha-defensins. Synthesis of alpha-defensin has been confirmed only in primates and glires to date and is presumably unique for a few tissues, including neutrophils and Paneth cells of the small intestine. Antimicrobial activities of these peptides were shown against a wide variety of microbes including bacteria, fungi, viruses and protozoan parasites. In the present study, we report the characterization of the equine a...
Bykovsky AF, Yershov FI, Zhdanov VM.Morphogenesis of Venezuelan equine encephalomyelitis virus was studied by means of electron microscopy. Virus-specific structures (factories, viroplasts) were found at early stages of infection; these structures were composed of fibrillar and cylindrical formations, aggregates of ribosomes, and viral nucleoids. The latter emerged from fibrillar and cylindrical structures. Aggregates of viral nucleoids were found in the cytoplasm and occasionally in the nuclei of virus-infected cells. Viral envelopes and mature virions were formed on the cell membranes and on the membranes of intracellular vacu...
Varga J, Fodor L, Rusvai M, Soós I, Makrai L.Two different, inactivated, aluminium salt adsorbed vaccines, one containing a R. equi strain (serotype 1, 10(9) CFU/ml and equine herpesvirus 2 (EHV-2) (1.5 x 10(7) PFU/ml) and another containing R. equi only were used on three studfarms to determine whether the disease can be prevented by vaccination of both pregnant mares and their foals. Pregnant mares received two 3 ml doses of vaccine intramuscularly 6 and 2 weeks before parturition and their foals were vaccinated on two or three occasions at 3, 5 or 7 weeks of age. The efficacy of the vaccines was evaluated on the basis of the clinical ...
Sugahara Y, Matsumura T, Kono Y, Honda E, Kida H, Okazaki K.Heparin extensively inhibited infection of MDBK cells by equine herpesvirus 1 (EHV-1) strains adapted to bovine cells or hamsters, while the reagent merely reduced infectivity of strains passaged only in equine cells. The gC of two strains adapted to non-equine cells seemed to have higher affinity for heparin, although the reagent bound to both the gC and gB of all strains tested. Amino acid substitutions of the gC of the EHV-1 strains adapted to non-equine cells converged on the hydrophilic regions, amino acid residues 92 to 175, resulting in the glycoprotein becoming more cationic. These res...
Brandt S, Schoster A, Tober R, Kainzbauer C, Burgstaller JP, Haralambus R, Steinborn R, Hinterhofer C, Stanek C.Equine hoof canker is a chronic proliferative pododermatitis of as yet unknown aetiology. Like equine sarcoid disease, canker is a therapy-resistant disorder characterised by hyperkeratosis, acanthosis and a marked tendency to recur. Objective: There is an association of sarcoid-inducing bovine papillomaviruses of types 1 and 2 (BPV-1, BPV-2) with hoof canker disease. Methods: Using PCR-based techniques, we assessed canker tissue, intact skin and/or peripheral blood mononuclear cells (PBMCs) of 25 canker-affected horses for the presence of sarcoid-associated BPV-1 and -2. Results: Conventional...
Higuchi T, Arakawa T, Hashikura S, Inui T, Senba H, Takai S.The effect on foals of prophylactic administration of hyperimmune plasma to prevent R. equi infection was investigated on three farms at which R. equi infection was endemic. Sixteen foals between 10 and 39 days of age were intravenously given 1-21 of hyperimmune plasma. ELISA antibody titres against R. equi were significantly increased and maintained at high levels for over 30 days in most of the recipient foals. The prevalence of R. equi infection was 6.3% (1/16) in the foals that received the immune plasma, and 26.3% (5/19) in the control foals not given the immune plasma on the three farms....
MacDonald DG, Morley PS, Bailey JV, Barber SM, Fretz PB.Post operative surgical wound infection rates were determined 452 cases of equine orthopaedic surgery performed at the Western College of Veterinary Medicine, Saskatoon, Saskatchewan, between January 1, 1981 and December 31, 1990. Only surgical procedures classified as clean or clean-contaminated by the National Research Council were included in this study. The overall post operative infection rate was 10.0% (45 of 452). Clean surgeries (n = 433) had an 8.1% infection rate while clean-contaminated surgeries (n = 19) had a 52.6% infection rate. Information collected from the medical records was...
Edington N, Bridges CG, Griffiths L.When 23 ponies were infected with equid herpesvirus-1 or -4 (EHV-1 or EHV-4), nasal shedding of interferon (IFN) correlated closely with the duration of viral excretion. Equine interferon (EqIFN) was detected in the serum only from animals infected with the EHV-1 virus, and here high levels correlated with clinical symptoms of locomotor disorder and indicated a poor prognosis. Low levels of IFN were detected in explanted mononuclear cells from ponies infected with either virus.
Anzai T, Eguchi M, Sekizaki T, Kamada M, Yamamoto K, Okuda T.In order to establish a rapid diagnostic method for contagious equine metritis (CEM), we developed and evaluated a polymerase chain reaction (PCR) test. Species-specific PCR primer sets were derived from the DNA sequence of a cloned DNA fragment of Taylorella equigenitalis that did not hybridize with the genome of a taxomonically related species, Oligella urethralis. Single step PCR with primer set P1-N2 and two-step semi-nested PCR with primer sets P1-N2 and P2-N2 detected as low as 100 and 10 CFU of the bacteria, respectively. Single-step PCR detected T. equigenitalis from genital swabs of e...
Niwa H, Hobo S, Kinoshita Y, Muranaka M, Ochi A, Ueno T, Oku K, Hariu K, Katayama Y.Salmonella enterica subsp. enterica serovar Abortusequi is a pathogen restricted to horses. Our investigation targeted 4 draft horses (9-10 months old) kept on a Japanese farm that had suffered an outbreak of S. Abortusequi abortion. The 4 horses were suspected to be carriers of the bacterium owing to their high agglutination titers (≥1:2,560) in tube agglutination testing. The owners' on-farm observations confirmed that the horses had no apparent abnormalities, and S. Abortusequi was not isolated from their blood, rectal swabs, or sternal bone marrow fluid at antemortem investigation. Howev...
Paz-Silva A, Francisco I, Valero-Coss RO, Cortiñas FJ, Sánchez JA, Francisco R, Arias M, Suárez JL, López-Arellano ME, Sánchez-Andrade R....The analysis of the capability of the nematode trapping-fungus Duddingtonia flagrans to adapt to the cyathostomin egg-output in horses was evaluated. Fecal samples from 196 pasturing autochthonous Pura Raza Galega horses were collected from the rectum and then divided according to the egg-output into three groups: ≤ 300, 310-800 and >800 eggs per gram feces. Four doses of chlamydospores (0.1, 0.2, 0.4 and 0.8 × 10(6)/100g feces) were directly spread onto fecal pats on the ground, remaining one without treatment as control. Fecal pats confirmed the presence of gastrointestinal nematode la...
Thanissery R, McLaren MR, Rivera A, Reed AD, Betrapally NS, Burdette T, Winston JA, Jacob M, Callahan BJ, Theriot CM.The relationship between the gut microbiota and Clostridioides difficile, and its role in the severity of C. difficile infection in humans is an area of active research. Intestinal carriage of toxigenic and non-toxigenic C. difficile strains, with and without clinical signs, is reported in animals, however few studies have looked at the risk factors associated with C. difficile carriage and the role of the host gut microbiota. Here, we isolated and characterized C. difficile strains from different animal species (predominantly canines (dogs), felines (cats), and equines (horses)) that were...
Várady M, Königová A, Corba J.The present study included 19 stud farms, including 243 horses, that were investigated for the occurrence of anthelmintic resistant cyathostomes. The number of horses on the farms varied from nine to more than 100, and horses of all ages were included. A minimum of seven horses were used for faecal egg count reduction (FECR) tests. The anthelmintics included were: fenbendazole (paste formulation), ivermectin (paste formulation) and pyrantel (powder). Resistance to benzimidazoles was detected on 14 farms, with FECR values ranging from 65.1 to 86.3%. Larval cultures after fenbendazole treatment ...
Hannant D, Mumford JA, Jessett DM.The duration of immunity as measured by virological, serological and clinical responses following infection with influenza A/equine/Newmarket/79 (H3N8) was assessed in repeated challenge experiments in which ponies were infected by exposure to aerosols of infectious virus. Previous infection stimulated complete clinical protection which persisted for at least 32 weeks as demonstrated by the absence of febrile responses and coughing in two groups of ponies infected 16 weeks or 32 weeks after the first infection. Partial clinical protection persisted for over a year as demonstrated by the absenc...
Moens Y, Lagerweij E, Gootjes P, Poortman J.The distribution of inspired gas to each lung, time constants of the lungs and parameters of gas exchange were studied in 2 groups of horses (mean bwt 606 kg), anaesthetised using thiopentone and chloral hydrate and breathing room air. One group (n = 4) had a downward curved abdominal contour (round-bellied) and the other group (n = 4) had an upward curved abdominal contour (flat-bellied). An equal distribution of inspired gas between the lungs existed in both groups in dorsal recumbency. Flat-bellied horses maintained this equal distribution in lateral recumbency whereas in round-bellied hors...
Chipangura JK, Chetty T, Kgoete M, Naidoo V.The continuous increase in prevalence of antimicrobial resistant bacteria presents a significant public health problem and is an indicator that antimicrobial prudent usage guidelines are not being followed, especially in developing countries. Despite trends being available from numerous countries, there is little published for South Africa. This study was aimed at estimating the prevalence and trends of antimicrobial resistance from bacterial isolates from equine clinical samples submitted for culture and susceptibility testing to the veterinary bacteriology laboratory of the University of Pre...
Duquesne F, Pronost S, Laugier C, Petry S.A direct-PCR assay was developed for the rapid detection of Taylorella equigenitalis, a Gram-negative bacterium responsible for contagious equine metritis (CEM) in Equidae. The bacteria may be detected in equine genital swabs without need for a preliminary step of DNA extraction or bacterial isolation. Specificity was determined with 125 isolates of T. equigenitalis, 24 isolates of Taylorella asinigenitalis, five commensal bacteria of the genital tract and a facultative intracellular pathogen of foals found in large concentration in soil. Our PCR is specific and amplified a 413-bp 16S ribosoma...
Wu W, Blythe DC, Loyd H, Mealey RH, Tallmadge RL, Dorman KS, Carpenter S.Two variants of equine infectious anemia virus (EIAV) that differed in sensitivity to broadly neutralizing antibody were tested in direct competition assays. No differences were observed in the growth curves and relative fitness scores of EIAVs of principal neutralizing domain variants of groups 1 (EIAV(PND-1)) and 5 (EIAV(PND-5)), respectively; however, the neutralization-resistant EIAV(PND-5) variant was less infectious in single-round replication assays. Infectious center assays indicated similar rates of cell-to-cell spread, which was approximately 1,000-fold more efficient than cell-free ...
Meana A, Pato NF, Martín R, Mateos A, Pérez-García J, Luzón M.An epidemiological study on equine cestodosis was carried out in central Spain. A total of 372 digestive tracts from equids slaughtered in abattoirs located in central Spain were studied from November 2001 to May 2004. Anoplocephala perfoliata was detected in 24% of the animals and Anoplocephala magna in 18%. Individual tapeworm burden was from 1 to 491 tapeworms for A. perfoliata and from 1 to 64 tapeworms for A. magna. Low tapeworm burdens (less than 30 cestodes) predominated significantly (p<0.01) in all seasons for both species. Seasonal prevalence of infection by A. perfoliata was signifi...
Fortier G, Pronost S, Miszczak F, Fortier C, Léon A, Richard E, Van Erck E, Thiry E, Lekeux P.During a case control study undertaken in 2006-2007, a screening and consensus polymerase chain reaction (PCR) was performed to evaluate the potential role of equid herpesviruses (EHV) in several occurrences of respiratory disorders in 661 horses. Of 785 bronchoalveolar or tracheal lavage fluid samples submitted for analysis, 20 were positive for EHV-5 DNA by sequential analysis of the consensus PCR product. Nineteen of those samples were confirmed using a specific EHV-5 PCR. No particular changes in cytological profile could be associated with the detection of EHV-5 in contrast to suggestions...
Kuttler KL, Zaugg JL, Gipson CA.The therapeutic efficacies of imidocarb and parvaquone were tested against Babesia equi of European origin in carrier horses and for induced acute infections in splenectomized ponies. Imidocarb, at a dosage of 4 mg/kg of body weight, given IM at 72-hour intervals 4 times, was ineffective in eliminating B equi-carrier infection in 9 mature geldings. A single IM administration of 4 mg/kg was not therapeutic in acutely infected splenectomized ponies. When given at 3 different dosages and treatment schedules, parvaquone was ineffective in clearing carrier infection. Parvaquone given IM once at a d...
Moyaert H, Decostere A, Vandamme P, Debruyne L, Mast J, Baele M, Ceelen L, Ducatelle R, Haesebrouck F.Gram-negative, curved, motile bacteria (strains EqF1T and EqF2) were isolated from faecal samples from two clinically healthy horses. Both strains possessed a single, monopolar, sheathed flagellum and were urease-negative. The novel strains grew at 37 degrees C under microaerobic conditions and were positive for oxidase, catalase and alkaline phosphatase activities. The isolates reduced nitrate to nitrite, but gamma-glutamyl transpeptidase activity was not detected. The novel isolates did not grow at 42 degrees C or on media containing 1 % glycine. They were resistant to cephalotin and nalidix...
Browning GF, Begg AP.Variant types of VP4 and VP7 gene segments of faecal rotaviruses from diarrhoeic foals were identified by restriction endonuclease digestion of reverse transcription/polymerase chain reaction (RT/PCR) products. The variants observed were correlated with serotypes by determination of the sequence of representative RT/PCR products (entire coding sequence for VP7 and the VP8 region of VP4) and comparison to published sequences of equine G and P serotype genes. Both G and P serotypes could be predicted for 95/116 (82%) strains, P serotype only for a further 8 (7%) strains and G serotype only for 1...
Watts DM, LeDuc JW, Bailey CL, Dalrymple JM, Gargan TP.Serological data accumulated during the past decade indicated that a variety of feral and domestic animals of the Delaware-Maryland-Virginia (DelMarVa) Peninsula were infected with Jamestown Canyon (JC) and/or Keystone (KEY) viruses (Bunyaviridae, California serogroup). Neutralizing (N) antibody to JC virus was most prevalent in white-tailed deer, sika deer, cottontail rabbits and horses. KEY virus N antibody was detected most frequently in gray squirrels and domestic goats. N antibody indicative of past infection by one or both viruses also was found in raccoons, horses and humans. JC and/or ...
Goodwin D, Gennari SM, Howe DK, Dubey JP, Zajac AM, Lindsay DS.Encephalitozoon cuniculi has been associated with natural cases of abortion and stillbirth in horses. However, little is known about the prevalence of this parasite in horses. We examined sera from 559 horses from Brazil for antibodies to E. cuniculi using the indirect immunofluorescent antibody (IFA) test and the direct agglutination test (DAT). We found that 79 (14.1%) were positive in the IFA test and 70 (12.5%) were positive in the DAT. Compared to the IFA as the "gold standard" the sensitivity of the DAG was 94.0% and the specificity was 96.1%. Our study indicates that horses in Brazil ar...
Lanz S, Gerber V, Marti E, Rettmer H, Klukowska-Rötzler J, Gottstein B, Matthews JB, Pirie S, Hamza E.Equine recurrent airway obstruction (RAO) is an inflammatory, obstructive airway disease induced by exposure of susceptible horses to inhaled organic dust particles. The immunological process underlying RAO is still unclear. Previous studies have shown that RAO is linked to the Interleukin-4 receptor (IL-4R) gene in one Warmblood family (F1), but not in another (F2). It has also been shown that in F1, but not in F2, RAO is associated with resistance against parasites, suggesting that this association may have an immuno-genetic basis. Therefore, we hypothesized that the T helper (h)1/Th2/regula...
Ellison SP, Omara-Opyene AL, Yowell CA, Marsh AE, Dame JB.A gene encoding a major 29 kDa surface antigen from Sarcocystis neurona, the primary causative agent of equine protozoal myeloencephalitis (EPM), was cloned, sequenced, and expressed as a recombinant protein. A cDNA library was prepared in the expression vector lambda ZAP from polyA+mRNA isolated from S. neurona merozoites cultivated in vitro. Random sequencing of 96 clones identified a clone of an abundant transcript having a translated amino acid sequence with 30% identity to the 31-kDa surface antigen of Sarcocystis muris cyst merozoites. Southern blot analysis indicated that the correspond...
Königová A, Várady M, Corba J.The objective of the study was to compare the in vitro egg hatch test (EHT), larval development test (LDT) and in vivo faecal egg count reduction test (FECR test) for the detection of benzimidazole resistance in equine strongyles. The presence of resistant or susceptible strongyle populations was determined in 25 stud farms using the in vivo FECR test and in vitro EHT. On the basis of the FECR values, resistance to fenbendazole was detected on 15 of the 25 farms (60%). The ED50 value (anthelmintic concentration producing 50% inhibition of hatching) for suspected resistant populations varied fr...
