The study of diseases in horses encompasses a wide range of conditions affecting equine health, including infectious diseases, metabolic disorders, and genetic abnormalities. These diseases can impact various systems within the horse, such as respiratory, gastrointestinal, and musculoskeletal systems, and can lead to significant health challenges. Research in this area focuses on understanding the pathophysiology, diagnosis, prevention, and treatment of equine diseases. Common diseases studied include equine influenza, equine herpesvirus, and laminitis. This page provides access to peer-reviewed research studies and scholarly articles that explore the etiology, clinical presentation, and management strategies of diseases in horses, contributing to the advancement of equine veterinary medicine.
De Paolis L, De Ciucis CG, Peletto S, Cappelli K, Mecocci S, Nervo T, Guardone L, Crescio MI, Pietrucci D, Fruscione F, Gabbianelli F, Turco S....Papillomavirus (PV) infections may be related to anogenital lesions and cancer development in humans and several other animal species. To date, 11 different PVs have been reported in horses. Among them, a newly described PV named Papillomavirus Type9 (EcPV9) was thus far only reported in the semen of a stallion with penile lesions in Australia. This study reports for the first time the presence of EcPV9 in asymptomatic Italian horses. From July 2020 to January 2022, genital brush samples were collected from 209 horses with no apparent signs of neoplastic disease and no PV-associated lesions, ...
Dauparaitė E, Kupčinskas T, Varady M, Petkevičius S.Control of strongyle infections presents a global challenge for horse practitioners due to the development of anthelmintic resistance (AR), however comprehensive information on AR in Lithuania is still lacking. The aim of this study was to assess the current situation of fenbendazole (FBZ) AR in horses at stable level in Lithuania. Results: Faecal samples from 121 horses from six stables were examined using the Mini-FLOTAC method. Of these, 89 horses met the inclusion criteria that included strongyle faecal egg counts (FEC) exceeding 200 eggs per gram (EPG). Faecal egg count reduction tests (F...
Kydd J, Nielsen M, Waller A.Julia Kydd, Martin Nielsen and Andrew Waller highlight some of the key presentations given at last year's 11th International Equine Infectious Diseases Conference, which was held virtually.
Suresh KP, Patil SS, Nayak A, Dhanze H, Rajamani S, Shivamallu C, Cull CA, Amachawadi RG.Brucellosis is a highly contagious bacterial disease that mainly affects ruminants, but it may affect equines, canines, and felines. The disease is of utmost significance from an economic standpoint in countries where there is no national brucellosis prevention and eradication policy in operation. A systematic review was done to estimate disease burden, incidences, prevalence, and geographical distribution critical in planning appropriate intervention strategies for the control and prevention of Brucellosis. Research articles that were published during the period 2000-2020 were considered for ...
Fürer F, Fraefel C, Lechmann J.Equid gammaherpesvirus 2 (EHV-2) and 5 (EHV-5) are widely distributed in the equines. Although their pathogenic potential is not yet fully understood, they appear to play a role in disease patterns like equine multinodular pulmonary fibrosis. In this study, a multiplex real-time PCR (rtPCR) was designed to detect DNA of the glycoprotein H (EHV-2) and E11 gene (EHV-5). Analytical specificity was determined by testing DNA of other herpesviruses by SYBR Green rtPCR and melting curve analysis, as well as Sanger sequencing of positive field samples. Analytical sensitivity was assessed by stand...
Anstey SI, Jenkins C, Jelocnik M.Chlamydia psittaci is a recognised cause of late-term equine foetal loss and poses a zoonotic risk in Australia. However, a management strategy is lacking to protect at-risk humans handling infected aborted material and pregnant mares. This study proposes a protocol for approaching C. psittaci foetal loss after investigating four foetal losses that occurred on a horse stud in the Hunter Valley, Australia in 2021. Swabs from the foetal loss cases (n = 4), close contact mares (n = 59), and foals of the close contact mares (n = 33) were collected and tested for C. psittaci using both isothe...
Wondimagegnehu K, Leta S, Amenu K, Negussie H.Respiratory disease is the most common presenting complaint at veterinary clinics and a priority concern for equid owners and veterinary practitioners in Ethiopia. This study aimed to report the molecular detection of EHV-2 and EHV-5 and to assess the risk factors associated with infection in working equids in central Ethiopia. Nasopharyngeal swabs were collected from 58 horses and donkeys to detect EHV-2 and EHV-5 using PCR targeting the conserved region of glycoprotein B (gB) genes. From 58 equids, EHV-5 and EHV-2 were detected in 20 (34.5%) and 19 (32.8%) equids, respectively. Concurrent in...
Meister TL, Arroyo LG, Shanahan R, Papapetrou MA, Reinecke B, Brüggemann Y, Todt D, Stang A, Hazlett M, Baird JD, Steinmann E.Theiler's disease (TD) is a (sub-)acute hepatitis in adult horses and one of the most common causes of acute hepatic failure. Recent findings indicate that equine parvovirus hepatitis (EqPV-H) likely causes TD and that its transmission occurs via iatrogenic and/or natural routes. Following the death of an EqPV-H positive mare with TD, close-contact mares and foals in the same paddock were monitored to evaluate if there was any evidence of EqPV-H. For this purpose, the serum of close contact horses was examined 6 and 42 days after the mare's death for the presence of EqPV-H DNA and changes in l...
Begg AP, Carrick J, Chicken C, Blishen A, Todhunter K, Eamens K, Jenkins C.This report describes the fetoplacental pathology of associated abortion, premature birth, and neonatal loss in 46 of 442 equine abortion investigations between 2015 and 2019. Seven abortions, 26 premature births, and 13 neonatal deaths with positive polymerase chain reaction (PCR) were evaluated. In 83% of cases (38/46), infection was considered as the primary cause of loss based on quantitative PCR (qPCR) confirmation, pathological findings, and exclusion of other causes, and was supported by immunolabeling in fetoplacental lesions. Lymphohistiocytic placentitis with vasculitis (36/38) af...
Arroyo LG, Hodgins DC, Guest B, Costa M, Ma Z, Monteiro MA.Clostridioides difficile (formerly Clostridium difficile) is associated with colitis in foals and mature horses. C. difficile exposes specific phosphorylated polysaccharides (PSs), named PS-I, PS-II and PS-III. These cell-surface PSs are potential vaccine targets, especially the hexasaccharide phosphate PS-II, that has been found in all C. difficile ribotypes examined. Since we previously identified anti-PS-II circulating antibodies in horses, we postulated that vaccinating foals with PS-II may prevent colonization by C. difficile. In this study, we aim to evaluate the IgM antibody response...
Makowiecki D, Chudziak W, Szczepanik P, Janeczek M, Pasicka E.Knowledge about horses from early medieval (10th-13th c.) Poland has been largely based on historical and archaeological data. Archaeozoological information has only been used to a limited extent. Therefore, this article aims to present the current state of knowledge on this subject, drawing on archaeozoological data from studies of horse bones. Apart from confirming earlier reflections regarding the sacred significance of the horse, additional information was obtained about specific individuals who were the subject of magical treatments. It turned out that sites with horse skeletons and skull...
McGovern KF, Gough RL.An 18 hours old foal presented with a suspected meconium impaction. There was no response to treatment and a tentative diagnosis of atresia coli (AC) was made. Surgical intervention was declined and the foal was euthanized 12 hours after admission. Type 3 AC was confirmed on post-mortem examination, with the colon ending at the left ventral colon. A 1,080 large colon volvulus (LCV) at the sternal flexure was present. It is speculated that AC could predispose the foal to LCV. Histopathology was not performed but would be useful in further cases of AC.
Ayoub C, Arroyo LG, Renaud D, Weese JS, Gomez DE.The objective of this study was to compare the fecal microbiota of two healthy teaching horse herds with that of client-owned horses from the same geographic areas. The fecal microbiota of client-owned horses from Ontario Canada (n = 15) and Florida, USA (n = 11) was compared with that teaching horses from the University of Guelph, Ontario, Canada (n = 10) and the University of Florida, Florida, USA (n = 15). The fecal microbiota was characterized by sequencing of bacterial DNA using the V4 hypervariable region of the 16S rRNA gene. The diversity (inverse Simpson index) of the fecal mi...
Ciaputa R, Gach J, Baranowski K, Dzimira S, Janus I, Kandefer-Gola M, Żebrowski K, Nowak M.An analysis of samples originating from domestic and exotic animals from Lower Silesia but also from other parts of Poland was carried out based on research conducted in 2014-2017. Unassigned: The materials used for the study were 11,338 tumour samples taken in vivo during surgery and as biopsies and posthumously during necropsies. They were sent to the Department of Pathology at Wrocław University of Environmental and Life Sciences for histopathological diagnosis. Unassigned: The largest group were canine tumours, of which there were 9,745 (85.95%), followed by feline tumours, totalling 1,39...
Onasanya AE, El-Hage C, Diaz-Méndez A, Vaz PK, Legione AR, Browning GF, Devlin JM, Hartley CA.Equid gammaherpesvirus 2 (EHV2) is a gammaherpesvirus with a widespread distribution in horse populations globally. Although its pathogenic significance can be unclear in most cases of infection, EHV2 infection can cause upper respiratory tract disease in foals. Co-infection of different strains of EHV2 in an individual horse is common. Small regions of the EHV2 genome have shown considerable genetic heterogeneity. This could suggest genomic recombination between different strains of EHV2, similar to the extensive recombination networks that have been demonstrated for some alphaherpesviruses. ...
Xu Z, Hao X, Li M, Luo H.Rhodococcus equi (R. equi) is a Gram-positive coccobacillus that causes pneumonia in foals of less than 3 months, which have the ability of replication in macrophages. The ability of R. equi persist in macrophages is dependent on the virulence plasmid pVAPA. Gram-positive extracellular vesicles (EVs) carry a variety of virulence factors and play an important role in pathogenic infection. There are few studies on R. equi-derived EVs (R. equi-EVs), and little knowledge regarding the mechanisms of how R. equi-EVs communicate with the host cell. In this study, we examine the properties of EVs prod...
Hassan Kadi R, Baghdadi AM.Lactic acid bacteria are microorganisms that can be present in meat, milk and fermented products, as well as fermented drinks and vegetables, and they inhibit the growth of pathogenic and decaying microorganisms. Our aim was isolating, screening, characterization and estimation of bacteriocin/s of Lactic acid bacteria isolated from Horses milk in Jeddah city, Saudi Arabia. That have antagonistic activity against a wide range of pathogenic bacteria. On MRS agar medium 16 LAB isolates were examined using the agar well diffusion method against the pathogenic bacteria (Gram-positive bacteria: S. a...
Abo-Aziza FAM, Hendawy SHM, Abdullah HHAM, El Namaky A, Laidoudi Y, Mediannikov O.Equine filariosis (EF) is a neglected vector-borne disease caused by nematode species belonging to the Onchocercidae and Setariidae families. Aside from their zoonotic potential, some species are responsible for serious health problems in equids worldwide, leading to significant economic difficulties. Here, we molecularly investigated equine blood samples (320 horses and 109 donkeys from Egypt) and four adult worms isolated from the peritoneal cavity of 5 out of the 94 slaughtered donkeys. In addition, quantitative enzyme-linked immunoassays (ELISAs) targeting circulating cytokines were used t...
Mayers J, Westcott D, Steinbach F.Using the commercially available PEPperCHIP® microarray platform, a peptide microarray was developed to identify immunodominant epitopes for the detection of antibodies against Equine arteritis virus (EAV). For this purpose, the whole EAV Bucyrus sequence was used to design a total of 1250 peptides that were synthesized and spotted onto a microarray slide. A panel of 28 serum samples representing a selection of EAV strains was tested using the microarray. Of the 1250 peptides, 97 peptides (7.76%) showed reactivity with the EAV-positive samples. No single peptide was detected by all the positi...
Klein C, Caston S, Troy J.Septic omphalophlebitis is a common disease process with a variety of morbidities and possible mortality. Affected umbilical remnant resection is highly successful but may not always be possible. Umbilical marsupialization can be implemented when total resection cannot be accomplished with minimally reported complications. Umbilical vein marsupialization was performed on three Percheron foals with extensive septic omphalophlebitis using the one-stage paramedian translocation technique and prolonged postoperative antimicrobial therapy. Long-term follow-up revealed herniation at the marsupializa...
Schrenk D, Bignami M, Bodin L, Chipman JK, Del Mazo J, Grasl-Kraupp B, Hogstrand C, Leblanc JC, Nielsen E, Ntzani E, Petersen A, Sand S, Schwerdtle T....In 2018, the EFSA Panel on Contaminants in the Food Chain (CONTAM) adopted a Scientific Opinion on the risks for animal health related to the presence of fumonisins, their modified forms and hidden forms in feed. A no observed adverse effect level (NOAEL) of 1 mg/kg feed was established for pigs. In poultry a NOAEL of 20 mg/kg feed and in horses a reference point for adverse animal health effect of 8.8 mg/kg feed was established, referred to as NOAEL. The European Commission (EC) requested EFSA to review the information regarding the toxicity of fumonisins for pigs, poultry and horses an...
Kudrimoti S, Machin J, Arojojoye AS, Awuah SG, Eisenberg R, Fenger C, Maylin G, Lehner AF, Tobin T.Based on structural similarities and equine administration experiments, Barbarin, 5-phenyl-2-oxazolidinethione from Brassicaceae plants, is a possible source of equine urinary identifications of aminorex, (R,S)-5-phenyl-4,5-dihydro-1,3-oxazol-2-amine, an amphetamine-related US Drug Enforcement Administration (DEA) controlled substance considered illegal in sport horses. We now report the synthesis and certification of d -barbarin to facilitate research on the relationship between plant barbarin and such aminorex identifications. D -barbarin synthesis commenced with production of d -2-oxo-2-phe...
Brown JA, Murphy BG, Clapp KS, LaDouceur EEB.Hypercementosis is infrequently reported to affect the cheek teeth of horses and presents as mineral deposits either attached (peripheral) or solitary ovoid (nodular) structures in the tooth bearing region. There is overlap between radiological and histological appearance of hypercementosis, cementoma, and equine odontoclastic tooth resorption and hypercementosis (EOTRH). The clinical presentation, imaging features, surgical management, and histological findings of nine horses that presented for dental lesions and associated hypercementosis of cheek teeth are reported. Horses were 4-15 years o...
Geiger T, Gerhards H, Bjelica B, Mackenthun E, Wollanke B.In the equine clinic of the LMU in Munich, therapeutic vitrectomies have been routinely performed in horses for three decades. The vitreous samples obtained during vitrectomies were usually tested for anti-Leptospira antibodies and for more than 20 years also by PCR for leptospiral DNA. If the indication for surgery was ophthalmologically inconclusive, an aqueous humor was collected preoperatively and examined for evidence of leptospiral infection. In this study, medical records from 2002 to 2017 were analyzed. Records for 1387 eyes affected by equine recurrent uveitis (ERU) and 237 eyes affec...
Toribio RE.A number of viruses transmitted by biological vectors or through direct contact, air, or ingestion cause neurologic disease in equids. Of interest are viruses of the Togaviridae, Flaviviridae, Rhabdoviridae, Herpesviridae, Bornaviridae, and Bunyaviridae families. Many are classified as arboviruses because they use arthropod vectors, whereas others are transmitted directly via ingestion, inhalation, or integument damage. The goal of this article is to provide an overview on pathophysiologic and clinical aspects of arboviruses of equine importance, including alphaviruses (Togaviridae) and flaviv...
Mouncey R, Arango-Sabogal JC, de Mestre A, Verheyen K.The study aimed to (1) describe the use of reproductive therapeutics; (2) estimate the incidence of disease and injury; and (3) describe non-reproductive medications administered during pregnancy in Thoroughbred broodmares. A prospective birth cohort was established on seven farms across the UK and Ireland. Details of dams' signalment, breeding history, reproductive management during the breeding season(s) and veterinary-attended episodes of illness or injury and medication usage during gestation were retrieved retrospectively for 275 pregnancies in 235 mares over two breeding seasons. Results...
Physick-Sheard P, Kraus M, Basrur P, McGurrin K, Kenney D, Schenkel F.To assess evidence for genetic contributions to atrial fibrillation (AF) in the Standardbred horse. Methods: Equine referrals to the Ontario Veterinary College Health Sciences Centre (OVCHSC) for 1985-2009, and age and gait matched breed registry controls. Methods: Breeds presenting ≥ 5 times annually were tabulated (admission year and diagnosis; total 40,039; AF 396; no AF 39,643), and breed and year effects examined. Heritability and inbreeding coefficients were determined for Standardbred AF cases and racing contemporaries, and odds ratios for AF were calculated for frequently occurring s...
Diallo IS, Hewitson GR, de Jong A, Kelly MA, Wright DJ, Corney BG, Rodwell BJ.Twelve nasal swabs were collected from yearling horses with respiratory distress and tested for equid herpesvirus 1 (EHV-1) and equid herpesvirus 4 (EHV-4) by real-time PCR targeting the glycoprotein B gene. All samples were negative for EHV-1; however, 3 were positive for EHV-4. When these samples were tested for EHV-2 and EHV-5 by PCR, all samples were negative for EHV-2 and 11 were positive for EHV-5. All three samples that were positive for EHV-4 were also positive for EHV-5. These three samples gave a limited CPE in ED cells reminiscent of EHV-4 CPE. EHV-4 CPE was obvious after 3 days and...
Arroyo LG, Weese JS, Staempfli HR.Despite empirical clinical association of infection with Clostridium difficile with colitis in horses, a causal link has not been confirmed. The objective of this study was to develop a model of C. difficile-associated diarrhea in foals with normal transfer of passive immunity. Nine 1-day-old pony foals were inoculated intragastrically with spores or vegetative cells of C. difficile. Five foals were challenged with spores, with 2 receiving 10(5) colony-forming units (CFUs) and concurrently 3 receiving 10(7) CFUs once daily for 3 days. Clindamycin was administered orally to disrupt gastrointest...
Levine JM, Ngheim PP, Levine GJ, Cohen ND.To determine sex, breed, and age distributions in a population of horses with cervical vertebral compressive myelopathy (CVCM), compared with contemporaneous control horses. Methods: Retrospective case-control study. Methods: 811 horses with CVCM and 805 control horses. Methods: The Veterinary Medical Database was searched to identify horses with CVCM and contemporaneous control horses registered between July 1974 and August 2007. Admission date, admitting institution, sex, breed, age at the time of registration in the database, weight, and discharge status (alive, died, or euthanized) were re...
Weese JS.Fortunately, MRSA infection and colonization are currently uncommon in veterinary medicine. Nevertheless, the increasing reports of the occurrence of MRSA infection in horses, veterinarians, and equine personnel dictate that serious consideration be given to the control of this pathogen in veterinary hospitals as well as in the equine community. It is unclear whether extrapolation from human hospitals and people in the community is appropriate; however, given the rapid increase in nosocomial MRSA in human hospitals and the recent shift of certain clones of MRSA into the community, it would be ...
Sequeira JL, Tostes RA, Oliveira-Sequeira TC.The objective of the present study was to investigate the prevalence of Gasterophilus nasalis larvae in Botucatu, the central west region of São Paulo State, Brazil, and to describe the lesions caused by the parasite. The climate of Botucatu is warm and rainy during the months of December through March and cool and dry during the months of May through August. The prevalence of G. nasalis was 16.84%, and the period of peak infestation corresponded to the months of cold and dry weather. The lesions detected at the sites of larval attachment were examined macro- and microscopically. Erosions and...
Molenkamp R, Greve S, Spaan WJ, Snijder EJ.Equine arteritis virus (EAV), the prototype arterivirus, is an enveloped plus-strand RNA virus with a genome of approximately 13 kb. Based on similarities in genome organization and protein expression, the arteriviruses have recently been grouped together with the coronaviruses and toroviruses in the newly established order Nidovirales. Previously, we reported the construction of pEDI, a full-length cDNA copy of EAV DI-b, a natural defective interfering (DI) RNA of 5.6 kb (R. Molenkamp et al., J. Virol. 74:3156-3165, 2000). EDI RNA consists of three noncontiguous parts of the EAV genome fused ...
Wilson AD, Heesom KJ, Mawby WJ, Mellor PS, Russell CL.IgE-mediated type 1 hypersensitivity reactions to the bites of insects are a common cause of skin disease in horses. Insect bite hypersensitivity (IBH) is most frequently associated with bites of Culicoides spp. and occurs in all parts of the world where horses and Culicoides coexist. The main allergens that cause IBH are probably some of the abundant proteins in the saliva of Culicoides associated with blood feeding. Western blots of Culicoides proteins separated by 1D gel-electrophoresis detected strong IgE responses in all horses with IBH to antigens in protein extracts from wild caught Cul...
Tadros EM, Frank N.To determine whether the method of lipopolysaccharide (LPS) administration (intermittent vs continuous) affects the magnitude and duration of the systemic inflammatory response in horses and whether prolonged (48 hours) endotoxemia induces laminitis. Methods: 12 healthy adult horses (10 mares and 2 geldings). Methods: Horses were randomly assigned to receive LPS (total dose, 80 μg; n = 4) or saline (0.9% NaCl) solution (80 mL/h; 4) via constant rate infusion or 8 bolus IV injections of LPS (10 μg, q 6 h;4) during a 48-hour period. Physical examinations were performed every 4 hours, inflammat...
Georges KC, Ezeokoli CD, Sparagano O, Pargass I, Campbell M, D'Abadie R, Yabsley MJ.Equine piroplasmosis due to Theileria equi and Babesia caballi is endemic in Trinidad. A case of equine piroplasmosis due to T. equi was diagnosed in a thoroughbred foal at 10h post-partum. A high parasitaemia (63%) of piroplasms was observed in a Wright-Giemsa(®) stained thin blood smear from the foal. In addition, the 18S rRNA gene for Babesia/Theileria was amplified from DNA extracted from the blood of the foal and the mare. Amplified products were subjected to a reverse line blot hybridization assay (RLB), which confirmed the presence of T. equi DNA in the foal. The mare was negative by R...
Gildea S, Arkins S, Walsh C, Cullinane A.Protection against equine influenza virus (EIV) relies largely on the production of circulating antibodies specific for the haemagglutinin (HA) glycoprotein. The objective of this study was to determine the antibody response of National Hunt horses in training to booster vaccination. The antibody response to the six equine influenza vaccines available in Ireland (three whole inactivated vaccines, two subunit vaccines and a canary pox recombinant vaccine), was monitored by single radial haemolysis (SRH) for six months post vaccination. There was no significant difference between antibody respon...
Moore BD, Balasuriya UB, Hedges JF, MacLachlan NJ.Equine viral arteritis (EVA) is an endotheliotropic viral disease of horses caused by equine arteritis virus (EAV). Although there is only one serotype of EAV, there is marked variation in the virulence of different strains of the virus. The replication and cytopathogenicity of three well-characterized strains of EAV of different virulence to horses were compared in rabbit kidney (RK-13) and primary equine pulmonary artery endothelial cells (ECs). Viral protein expression, plaque size, and cytopathogenicity of all three viruses were similar in RK-13 cells, whereas two virulent strains of EAV w...
AIDS reviewsNovember 6, 2003
Volume 5, Issue 3 156-164
Towers GJ, Goff SP.Pathogenic retroviruses have driven the evolution of several dominant-acting mechanisms able to block infection and protect the host. These are exemplified by the mouse gene Fv1, which encodes a Gag-like protein able to protect against murine leukemia virus (MLV) infection. The block is saturable, occurs after reverse transcription and is directed against the viral capsid gene. Several other mammalian species are also able to block MLV infection with the same capsid specificity. A human gene with this activity has been named Ref1. Recently, primates have been shown to restrict a variety of ret...
Fagerness AJ, Flaherty MT, Perry ST, Jia B, Payne SL, Fuller FJ.Equine infectious anemia virus (EIAV) is a macrophage-tropic lentivirus that persistently infects horses and causes a disease that is characterized by periodic episodes of fever, thrombocytopenia, and viremia. EIAV encodes only four regulatory/accessory genes, (tat, rev, ttm, and S2) and is the least genetically complex of all known lentiviruses. We sought to determine the role of the EIAV S2 accessory gene of EIAV by introducing mutations that would prevent S2 expression on the p19/wenv17 infectious molecular clone. Virus derived from the p19/wenv17 molecular clone is highly virulent and rout...
Båverud V, Franklin A, Gunnarsson A, Gustafsson A, Hellander-Edman A.In Sweden, mares sometimes develop acute, often fatal, colitis when their foals are treated orally with erythromycin and rifampicin for Rhodococcus (R.) equi infection. Clostridium (C.) difficile, or its cytotoxin, was demonstrated in faecal samples from 5 of 11 (45%) mares with diarrhoea. By contrast C. difficile was not found in the faecal flora of 12 healthy mares with foals treated for R. equi infection or in 56 healthy mares with healthy untreated foals. No other enteric pathogen was isolated from any diarrhoeic mare. Of 7 investigated treated foals, 4 had a high (1651.0, 1468.3, 273.0 an...
Balasuriya UBR, Hedges JF, Smalley VL, Navarrette A, McCollum WH, Timoney PJ, Snijder EJ, MacLachlan NJ.Equine arteritis virus (EAV) causes a persistent infection of the reproductive tract of carrier stallions. The authors determined the complete genome sequences of viruses (CW96 and CW01) that were present 5 years apart in the semen of a carrier stallion (CW). The CW96 and CW01 viruses respectively had only 85.6 % and 85.7 % nucleotide identity to the published sequence of EAV (EAV030). The CW96 and CW01 viruses had two 1 nt insertions and a single 1 nt deletion in the leader sequence, and a 3 nt coding insertion in ORF1a; thus their genomes included 12 708 nt as compared to the 12 704 nt in EA...
Kuroda T, Kinoshita Y, Niwa H, Shinzaki Y, Tamura N, Hobo S, Kuwano A.Meticillin-resistant Staphylococcus aureus (MRSA) infections have been confirmed in hospitalised Thoroughbred racehorses at the hospitals of two training centres in Japan since 2009. To investigate the source of infection, the authors examined the rate of nasal MRSA colonisation in 600 healthy Thoroughbred racehorses, 53 veterinarians and 16 office staff at the racehorse hospitals of the two training centres. MRSA was not isolated from healthy Thoroughbred racehorses or hospital office staff. However, MRSA was isolated from 16 veterinarians (30.1 per cent), and the colonisation rate was signif...
Bogaert L, Martens A, Kast WM, Van Marck E, De Cock H.Bovine papillomavirus (BPV)-1 and -2 is linked to equine sarcoids, a commonly observed skin tumor in horses that is of considerable veterinary importance. Previous studies using in situ hybridization have detected BPV DNA only in fibroblasts and not in keratinocytes of sarcoids. In contrast, normal equine skin latently infected with BPV shows a dysplastic epithelium without dermal changes, similar to lesions induced by other papillomavirus types infecting the epithelium. The first goal of our study was to describe the epidermal and dermal characteristics of several stages in sarcoid developmen...
Karakulska J, Fijałkowski K, Nawrotek P, Pobucewicz A, Poszumski F, Czernomysy-Furowicz D.The aim of this study was an analysis of the staphylococcal flora of the nasal cavity of 42 healthy horses from 4 farms, along with species identification of CoNS isolates and determination of resistance to 18 antimicrobial agents, particularly phenotypic and genotypic methicillin resistance. From the 81 swabs, 87 staphylococci were isolated. All isolates possessed the gap gene but the coa gene was not detected in any of these isolates. Using PCR-RFLP of the gap gene, 82.8% of CoNS were identified: S. equorum (14.9%), S. warneri (14.9%), S. sciuri (12.6%), S. vitulinus (12.6%), S. xylosus (11....
Foreman JH.Exhaustion occurs in most equestrian sports, but it is more frequent in events that require sustained endurance work such as endurance racing, three-day eventing, trial riding, and hunting. Exhaustion is also more likely when an unfit, unacclimatized, or unsound horse is exercised. Mechanisms that contribute to exhaustion include heat retention, fluid and electrolyte loss, acid-base imbalance, and intramuscular glycogen depletion. Clinical signs include elevated temperature, pulse, and respiratory rate; depression; anorexia; unwillingness to continue to exercise; dehydration; weakness; stiffne...
Kinde H, Mathews M, Ash L, St Leger J.Two horses, a 16-year-old male Holsteiner and a 5-year-old male miniature horse, were diagnosed with halicephalobiasis at the California Veterinary Diagnostic Laboratory System, San Bernardino Branch, in April and June of 1998. Over a period of 4 weeks, the Holsteiner horse developed renal dysfunction, blepharospasm, and blindness in the right eye. A 15-cm-diameter mass was detected on ultrasound examination in the right kidney. Terminally, the animal developed seizures and was euthanized. The miniature horse had a 6-week-long illness characterized by testicular enlargement and uveitis. This a...
Bourély C, Cazeau G, Jarrige N, Haenni M, Gay E, Leblond A.Horses are one of the potential reservoirs of antimicrobial resistance (AMR) determinants that could be transferred to human subjects. Objective: To describe the AMR patterns of major bacteria isolated from diseased horses in France. Methods: Retrospective observational study. Methods: Data collected between 2012 and 2016 by RESAPATH, the French national surveillance network for AMR, were analysed. Only antimicrobials relevant in veterinary and human medicine for the isolated bacteria were considered. Mono- and multidrug resistance were calculated. The resistance proportions of major equine di...
Reef VB, Vaala WE, Worth LT, Sertich PL, Spencer PA.Mares with complicated pregnancies (illness, problems at parturition or delivery of an abnormal foal, n = 30) were scanned transabdominally from 298 days gestation to term in order to measure fetal size, evaluate fetal well-being and characterise the intrauterine environment. The results of the last scan obtained prior to parturition were compared to normal data obtained from fetuses of comparable gestational age to develop a biophysical profile specific for the equine fetus. Twelve mares produced a normal foal (positive outcome) and 18 mares delivered 19 abnormal foals (negative outcome). Bot...
Den Boon JA, Spaan WJ, Snijder EJ.The expression of the genetic information of equine arteritis virus (EAV), an arterivirus, involves the synthesis of six subgenomic (sg) mRNAs. These are 5' and 3' coterminal since they are composed of a leader and a body sequence, which are identical to the 5' and 3' ends of the genome, respectively. Previously, it has been suggested that cis-splicing of a genome-length precursor RNA is involved in their synthesis. This was reevaluated in a comparative analysis of the sg RNA synthesis of EAV, the coronavirus mouse hepatitis virus (MHV), and the alphavirus Sindbis virus. UV transcription mappi...
Liepman RS, Swink JM, Habing GG, Boyaka PN, Caddey B, Costa M, Gomez DE, Toribio RE.Alterations in the gastrointestinal microbiota after antimicrobial therapy in horses can result in loss of colonization resistance and changes in bacterial metabolic function. It is hypothesized that these changes facilitate gastrointestinal inflammation, pathogen expansion and the development of diarrhea. The objectives of this study were to determine the effect of intravenous administration of antimicrobial drugs (ceftiofur, enrofloxacin, oxytetracycline) on equine fecal bacterial communities over time, to investigate whether those changes are detectable after 5 days of treatment and whether...
Diaz-San Segundo F, Dias CC, Moraes MP, Weiss M, Perez-Martin E, Owens G, Custer M, Kamrud K, de los Santos T, Grubman MJ.We have previously shown that delivery of the porcine type I interferon gene (poIFN-α/β) with a replication-defective human adenovirus vector (adenovirus 5 [Ad5]) can sterilely protect swine challenged with foot-and-mouth disease virus (FMDV) 1 day later. However, the need of relatively high doses of Ad5 limits the applicability of such a control strategy in the livestock industry. Venezuelan equine encephalitis virus (VEE) empty replicon particles (VRPs) can induce rapid protection of mice against either homologous or, in some cases, heterologous virus challenge. As an alternative approach ...
Robertson AT, Caughman GB, Gray WL, Baumann RP, Staczek J, O'Callaghan DJ.Equine herpesvirus type 1 (EHV-1) gene expression is coordinately regulated in an alpha, beta, gamma fashion. Viral alpha gene products include a 6.0-kb immediate early (IE) mRNA species (W. L. Gray et al., 1987, Virology 158, 79-87) and at least four closely related IE polypeptides (IEPs) (G.B. Caughman et al., 1985, Virology 145, 49-61). In this report, we describe results obtained from a series of in vitro translation experiments which were performed in an effort to characterize the IEPs and identify the mechanism by which individual IE protein species are generated. Our data indicate that ...
Gibson CA, Daniels RS, Oxford JS, McCauley JW.The nucleotide sequences of ten haemagglutinin genes of representative H7N7 equine influenza viruses isolated between 1956 and 1977 have been determined by primer extension sequencing. Their nucleotide and deduced amino acid sequences demonstrate a high degree of homology. These equine viruses can be divided into two distinct subgroups, the prototype-like, and a group comprising the early American isolates and the remaining equine viruses. The equine H7 haemagglutinins form a quite distinct group compared to H7 haemagglutinins isolated from other species. Each of these equine H7 haemagglutinin...
Montagnier L.Recent data indicate that the lymphadenopathy-associated virus (LAV) is morphologically similar to animal lentiviruses, such as equine infectious anemia and visna viruses. This finding, together with the cross-reactivity of the core proteins of LAV with those of the equine infectious anemia virus and a similarity in genome structure and biological properties, allows LAV to be placed in the retroviral subfamily of Lentivirinae. Molecular data indicate a high degree of genetic variation of the virus, especially in the envelope gene, which have important implications for the origin of the virus (...
Morley PS, Hanson LK, Bogdan JR, Townsend HG, Appleton JA, Haines DM.Antibodies specific for equine influenza viruses are usually quantified using single radial hemolysis (SRH), hemagglutination inhibition (HI) or virus neutralization (VN). Neutralizing antibodies are thought to provide optimum protection to challenged animals. The purpose of this study was to determine the extent to which SRH and HI assays detect antibodies which neutralize equine influenza viruses. Acute and convalescent sera from 41 horses were analyzed using VN, SRH, and HI assays. These horses were present in a population of Thoroughbred racehorses during an epidemic of upper respiratory t...
