Serotypes refer to distinct variations within a species of microorganisms, classified based on the antigens present on their surface. In horses, understanding serotypes is important for identifying different strains of pathogens, such as bacteria and viruses, that can cause disease. This classification aids in the development of targeted vaccines and treatments by identifying the specific serotype responsible for an infection. Common pathogens in horses with multiple serotypes include equine influenza virus and Streptococcus equi, the causative agent of strangles. This page compiles peer-reviewed research studies and scholarly articles that explore the identification, classification, and implications of serotypes in equine health and disease management.
Ronchi GF, Ulisse S, Rossi E, Franchi P, Armillotta G, Capista S, Peccio A, Di Ventura M, Pini A.Monovalent, inactivated and adjuvanted vaccines against African horse sickness, prepared with serotypes 5 and 9, were tested on guinea-pigs to select the formulation that offered the greatest immunity. The final formulation of the vaccines took into account the immune response in the guinea-pig and the inflammatory properties of two types of adjuvant previously tested on target animals. A pilot study was subsequently conducted on horses using a vaccine prepared with serotype 9. The vaccine stimulated neutralising antibodies from the first administration and, after the booster dose, 28 days lat...
Ishihara A, Bartlett JS, Bertone AL.Intra-articular gene therapy has potential for the treatment of osteoarthritis and rheumatoid arthritis. To quantify in vitro relative gene transduction, equine chondrocytes and synovial cells were treated with adenovirus vectors (Ad), serotype 2 adeno-associated virus vectors (rAAV2), or self-complementary (sc) AAV2 vectors carrying green fluorescent protein (GFP). Using 6 horses, bilateral metacarpophalangeal joints were injected with Ad, rAAV2, or scAAV2 vectors carrying GFP genes to assess the in vivo joint inflammation and neutralizing antibody (NAb) titer in serum and joint fluid. In vit...
Ferris NP, Clavijo A, Yang M, Velazquez-Salinas L, Nordengrahn A, Hutchings GH, Kristersson T, Merza M.Two lateral flow devices (LFD) for the detection of vesicular stomatitis (VS) virus (VSV), types Indiana (VSV-IND) and New Jersey (VSV-NJ) were developed using monoclonal antibodies C1 and F25VSVNJ-45 to the respective VSV serotypes. The performance of the LFDs was evaluated in the laboratory on suspensions of vesicular epithelia and cell culture passage derived supernatants of VSV. The collection of test samples included 105 positive for VSV-IND (92 vesicular epithelial suspensions and 13 cell culture antigens; encompassing 93 samples of subtype 1 [VSV-IND-1], 9 of subtype 2 [VSV-IND-2] and 3...
Blatti S, Overesch G, Gerber V, Frey J, Hüssy D.A retrospective, cross-sectional study was conducted to determine the leptospiral seroprevalence in clinically healthy horses in Switzerland. A representative sample of 615 horse sera was examined by microscopic agglutination test for the presence of antibodies against 15 Leptospira spp. serovars. In total, 58.5 % (n = 360) of the horses were positive for one or more of the antigens analysed, with 20.3 % of them showing titres >= 400. The most prevalent serovar was Pyrogenes (22.6 %), followed by serovars Canicola (22.1 %) and Australis (19.2 %). Older horses, mares, ponies and ani...
Horsington JJ, Gilkerson JR, Hartley CA.Erbovirus is a genus of the family Picornaviridae and equine rhinitis B virus (ERBV) is the sole species. Erboviruses infect horses causing acute respiratory disease and sub-clinical and persistent infections. Despite the high seroprevalence and worldwide distribution of these viruses, the pathogenesis and antigenic structure of the three ERBV serotypes (ERBV1, 2 and 3) is poorly understood. To characterise linear epitopes on ERBV structural proteins, a set of fusion proteins were expressed in Escherichia coli. These proteins were tested in Western blot and ELISA and reactive proteins were als...
Oura CA, Ivens PA, Bachanek-Bankowska K, Bin-Tarif A, Jallow DB, Sailleau C, Maan S, Mertens PC, Batten CA.African horse sickness virus serotype 9 (AHSV-9) has been known for some time to be circulating amongst equids in West Africa without causing any clinical disease in indigenous horse populations. Whether this is due to local breeds of horses being resistant to disease or whether the AHSV-9 strains circulating are avirulent is currently unknown. This study shows that the majority (96%) of horses and donkeys sampled across The Gambia were seropositive for AHS, despite most being unvaccinated and having no previous history of showing clinical signs of AHS. Most young horses (<3 years) were seropo...
Horsington JJ, Gilkerson JR, Hartley CA.Equine rhinitis B virus (ERBV) is the single species in the genus Erbovirus, family Picornaviridae. Equine rhinitis B viruses exist in three serotypes and are associated with respiratory disease in horses. Members of the species vary in stability at acid pH. To date there has been discordance in genotype, serotype and acid stability phenotype groupings. To identify capsid regions associated with acid stability, two viruses were serially treated at pH 3.3 to isolate acid-stable mutants. An acid-stable mutant of the prototype acid-labile serotype 1 virus contained a single amino acid change in t...
Tseng CT, Miller D, Cassano J, Bailey E, Antczak DF.A system for identifying equine major histocompatibility complex (MHC) haplotypes was developed based on five polymorphic microsatellites located within the MHC region on ECA 20. Molecular signatures for 50 microsatellite haplotypes were recognized from typing 353 horses. Of these, 23 microsatellite haplotypes were associated with 12 established equine leucocyte antigen (ELA) haplotypes in Thoroughbreds and Standardbreds. Five ELA serotypes were associated with multiple microsatellite subhaplotypes, expanding the estimates of diversity in the equine MHC. The strong correlations between serolog...
Buss DG, Giuliano E, Sharma A, Mohan RR.To determine if hybrid adeno-associated virus serotype 2/5 (AAV5) vector can effectively deliver foreign genes into the equine cornea without causing adverse side effects. The aims of this study were to: (i) evaluate efficacy of AAV5 to deliver therapeutic genes into equine corneal fibroblasts (ECFs) using enhanced green fluorescent protein (EGFP) marker gene, and (ii) establish the safety of AAV5 vector for equine corneal gene therapy. Methods: Primary ECF cultures were harvested from healthy donor equine corneas. Cultures were maintained at 37°C in humidified atmosphere with 5% CO(2). Metho...
Phalen DN, Drew ML, Simpson B, Roset K, Dubose K, Mora M.Cattle Egrets have a worldwide distribution, feed in proximity to cattle and other domestic animals, and often nest in large colonies in urban woodlots. Over a 3-yr period, nestlings from five Cattle Egret colonies from Central Texas, USA, were surveyed for salmonellosis. Prevalence of infection ranged from 29% to 95%. Seventeen Salmonella enterica subsp. enterica serotypes were isolated, of which the 4,5,12:i-monophasic serotype predominated in cultures of both the digestive tract and pooled spleen and liver. Of 11 4,5,12:i-monophasic isolates phage typed, eight were determinate type 193. The...
Yan W, Faisal SM, Divers T, McDonough SP, Akey B, Chang YF.Little information is available about experimental induction of leptospirosis in horses. Objective: Determine serologic, hematologic responses of horses to Leptospira interrogans serovar Kennewicki infection. Methods: Four adult horses seronegative for leptospirosis. Methods: Experimental and observational study. Horses were challenged with an equine isolate of L. interrogans serovar Kennewicki at 2 different doses and different inoculation sites. After challenge, the horses were monitored for 60 days. Blood, urine, and aqueous humor samples were collected at intervals until euthanasia 60 days...
von Teichman BF, Dungu B, Smit TK.The polyvalent African horsesickness (AHS) attenuated live virus (AHS-ALV) vaccine produced at Onderstepoort Biological Products incorporates 7 of the 9 known serotypes circulating in southern Africa. Serological cross-reaction has been shown in vitro to Serotypes 5 and 9 by Serotypes 8 and 6 respectively, but the degree of in vivo cross-protection between these serotypes in vaccinated horses has not previously been reported. Due to the increasing incidence of AHS Serotypes 5 and 9 in the field, over the last 3-4 seasons of AHS in South Africa, and the absence of Serotypes 5 and 9 in the AHS-A...
Matsuo E, Celma CC, Roy P.African horse sickness virus (AHSV), a member of the orbivirus genus of the family Reoviridae, is an insect-vectored pathogen of horses of concern to the equine industry. Studies on AHSV replication and pathogenesis have been hampered by the lack of reverse genetics allowing targeted mutation of viral genomes. We demonstrate that AHSV single-stranded RNA synthesized in vitro (core transcripts) is infectious and that there are distinct primary and secondary stages of the replication cycle. Transfection with a mixture of core transcripts from two different serotypes or a mixture of core transcri...
Clift SJ, Penrith ML.Tissues from 196 experimental and confirmed natural cases of African horse sickness (all 9 serotypes) were examined with a standardized and validated immunohistochemical assay for detection of the causative virus. The study confirmed that heart and lung are the main target tissues for African horse sickness virus (across all serotypes), followed closely by spleen. It also indicated that microvascular endothelial cells and monocyte-macrophages are the main target cells for virus replication. The importance of monocytes as target cells was emphasized, with relatively few tissue macrophages conta...
Echeverría MG, Díaz S, Metz GE, Serena MS, Panei CJ, Nosetto E.Equine viral arteritis (EVA) is a contagious viral disease that frequently causes mild or subclinical infections in adult horses. Only one EAV serotype has been described. However, there are differences in antigenicity, pathogenicity and neutralization characteristics of virus field strains. The interaction of two viral proteins, GP5 and M, is critical for infectivity and amino acid changes in the GP5 sequences have an effect on the neutralizing phenotype, regardless the effects of other viral proteins. The objective of the present study was to evaluate the neutralization phenotypes of the 5 u...
Nemoto M, Hata H, Higuchi T, Imagawa H, Yamanaka T, Niwa H, Bannai H, Tsujimura K, Kondo T, Matsumura T.We evaluated antigen detection kits for human rotavirus with regard to their usefulness for diagnosing equine rotavirus infection. Limiting dilution analyses showed that of the seven kits investigated the Dipstick `Eiken' Rota (Dipstick) had the highest sensitivity to two serotypes of equine rotavirus. The Dipstick did not cross-react with several equine intestinal pathogens. An investigation using 249 fecal samples indicated that the sensitivity of the Dipstick was 81.9% and 47.3%, and its specificity was 98.2% and 99.0%, and its concordance rate was 92.8% and 68.3%, compared with values obta...
Quan M, Lourens CW, MacLachlan NJ, Gardner IA, Guthrie AJ.Nucleotide sequences of 52 South African isolates of African horse sickness virus (AHSV) collected during 2004-2005 and including viruses of all nine AHSV serotypes, were used to design and develop a duplex real-time reverse transcription quantitative PCR (RT-PCR) assay targeting the VP7 (S8) and NS2 (S9) genes of AHSV. The assay was optimized for detection of AHSV in fresh and frozen blood of naturally infected horses. Assay performance was enhanced using random hexamers rather than gene-specific primers for RT, and with denaturation of double-stranded RNA in the presence of random hexamers. ...
Giles C, Cavanagh HM, Noble G, Vanniasinkam T.There are currently two known serotypes of equine adenovirus (EAdV), equine adenovirus type 1 (EAdV1) and equine adenovirus type 2 (EAdV2); EAdV1 is predominantly associated with upper respiratory tract infections while EAdV2 appears to have a higher association with gastrointestinal infection, however, very little is known about the prevalence of these viruses in horse populations in Australia. In this study we tested 122 serum samples obtained from horses in New South Wales, Australia, using a standard serum neutralization (SN) assay and ELISA. Ninety-seven of the 122 sera displayed had mode...
Attoui H, Mendez-Lopez MR, Rao S, Hurtado-Alendes A, Lizaraso-Caparo F, Mohd Jaafar F, Samuel AR, Belhouchet M, Pritchard LI, Melville L, Weir RP....During 1997, two new viruses were isolated from outbreaks of disease that occurred in horses, donkeys, cattle and sheep in Peru. Genome characterization showed that the virus isolated from horses (with neurological disorders, 78% fatality) belongs to a new species the Peruvian horse sickness virus (PHSV), within the genus Orbivirus, family Reoviridae. This represents the first isolation of PHSV, which was subsequently also isolated during 1999, from diseased horses in the Northern Territory of Australia (Elsey virus, ELSV). Serological and molecular studies showed that PHSV and ELSV are very s...
Goodrich LR, Choi VW, Carbone BA, McIlwraith CW, Samulski RJ.Cell transplantation for the treatment of joint disease is an important clinical tool. Genetic modification of cells before transplantation has shown enhanced healing. Ex vivo genetic modification of joint tissue cells with various adeno-associated virus (AAV) serotypes has not been investigated. The transduction efficiencies of self-complementary AAV serotypes (1-6 and 8) were determined in joint tissue containing chondrocytes and synoviocytes isolated from equine models. When comparing scAAV serotypes for efficient transduction ex vivo, in chondrocytes versus synoviocytes, serotypes 6 and 2,...
Stahl C, Unger L, Mazuet C, Popoff M, Straub R, Frey J.Botulinum neurotoxins, predominantly serotypes C and D, cause equine botulism through forage poisoning. The C-terminal part of the heavy chain of botulinum neurotoxin types C and D (HcBoNT/C and D) was expressed in Escherichia coli and evaluated as a recombinant mono- and bivalent vaccine in twelve horses in comparison to a commercially available toxoid vaccine. A three-dose subcutaneous immunization of adult horses elicited robust serum antibody response in an ELISA using the immunogen as a capture antigen. Immune sera showed dose-dependent high potency in neutralizing specifically the active...
Lee HS, Heo EJ, Jeoung HY, Ko HR, Kweon CH, Youn HJ, Ko YJ.In this study, an enzyme-linked immunosorbent assay (ELISA) using glycoprotein and a monoclonal antibody (MAb) was developed for the detection of antibodies to vesicular stomatitis virus (VSV) serotype New Jersey (NJ). The glycoprotein to be used as a diagnostic antigen was extracted from partially purified VSV-NJ, and a neutralizing MAb specific to VSV-NJ was incorporated to compete with antibodies in a blocking ELISA using glycoprotein (GP ELISA). The cutoff of the GP ELISA was set at 40% inhibition, which corresponded to a virus neutralization test (VNT) titer of 32. With this threshold, th...
Aradaib IE.A nested reverse transcriptase (RT) polymerase chain reaction (RT-PCR), for rapid detection of African horse sickness virus (AHSV) double-stranded ribonucleic acid (dsRNA) in cell culture and tissue samples, was developed and evaluated. Using an outer pair of primers (P1 and P2), selected from genome segment three of AHSV serotype 6 (AHSV-6), the RT-PCR-based assay resulted in amplification of a 890 base pair (bp) primary PCR product. RNAs from the nine vaccine strains of AHSV, and a number of AHSV field isolates including the Central African isolates of AHSV-9 and AHSV-6, propagated in cell c...
Makrai L, Dénes B, Hajtós I, Fodor L, Varga J.Two hundred and twelve Rhodococcus equi strains were isolated from soil, nasal and rectal swabs of horses and immunocompromised human patients in Hungary and serotyped using Prescott's serotyping system. One hundred and forty-seven strains (69.3%) belonged to serotype 1, 22 strains (10.4%) to serotype 2, 6 strains (2.8%) to serotype 3 and 1 strain (0.5%) to serotype 4. Serotypes 5, 6 and 7 were not found and 36 strains (17%) could not be typed. Serotype 1 (72%) was the type most commonly isolated from clinical samples of foals or from the soil of horse facilities. Six out of 8 R. equi strains ...
Howell PG, Nurton JP, Nel D, Lourens CW, Guthrie AJ.Cohorts of yearlings were sampled over a period of 6 years in a retrospective serological survey to establish the annual prevalence of serotype specific antibody to equine encephalosis virus on Thoroughbred stud farms distributed within defined geographical regions of South Africa. Seasonal seroprevalence varied between 3.6% and 34.7%, revealing both single and multiple serotype infections in an individual yearling. During the course of this study serotypes 1 and 6 were most frequently and extensively identified while the remaining serotypes 2, 3, 4, 5 and 7 were all identified as sporadic and...
Fernández-Pinero J, Fernández-Pacheco P, Rodríguez B, Sotelo E, Robles A, Arias M, Sánchez-Vizcaíno JM.A highly sensitive and specific TaqMan-MGB real-time RT-PCR assay has been developed and standardised for the detection of African horse sickness virus (AHSV). Primers and MGB probe specific for AHSV were selected within a highly conserved region of genome segment 7. The robustness and general application of the diagnostic method were verified by the detection of 12 AHSV isolates from all of the nine serotypes. The analytical sensitivity ranged from 0.001 to 0.15 TCID(50) per reaction, depending on the viral serotype. Real-time PCR performance was preliminarily assessed by analysing a panel of...
Vinogradov E, MacLean LL, Brooks BW, Lutze-Wallace C, Perry MB.Taylorella asinigenitalis sp. nov is a nonpathogenic gram-negative bacterium recently isolated from the genital tract of male donkeys. The bacterium is phenotypically indistinguishable from Taylorella equigenitalis, a pathogen that is the cause of contagious equine metritis, a highly communicable venereal disease of horses. The structural analysis of the lipopolysaccharide produced by T. asinigenitalis sp. nov (ATCC 700933) demonstrated that its O-polysaccharide (O-PS) component is a linear unbranched polymer of repeating disaccharide units composed of 1,3-linked pyranosyl residues of 2,4-diac...
Turton JF, Baklan H, Siu LK, Kaufmann ME, Pitt TL.A multiplex PCR using targets within the serotype-specific region of the capsular polysaccharide synthesis gene cluster of serotypes K1, K2 and K5 was evaluated using the 77 reference serotype strains of Klebsiella, and a panel of clinical isolates subjected previously to conventional serotyping. The PCR was highly specific for these serotypes, which are those most associated with virulence in humans and horses. PCR confirmed that isolates of the K5 serotype had cross-reacted with antiserum for other serotypes, particularly for K7. K5 isolates received by our laboratory were almost exclusively...
Agüero M, Gómez-Tejedor C, Angeles Cubillo M, Rubio C, Romero E, Jiménez-Clavero A.African horse sickness is an arthropod-borne disease of the equine included in the World Organization for Animal Health (OIE) list with important economic consequences for horse trade. The disease is caused by African horse sickness virus (AHSV; family Reoviridae, genus Orbivirus), which is transmitted by Culicoides midges. It is endemic in sub-Saharan Africa, spreading occasionally outside this area where the occurrence of Culicoides vectors allows virus transmission. Currently, only conventional (gel-based) reverse transcription polymerase chain reaction (RT-PCR) protocols are available for ...
Quan M, van Vuuren M, Howell PG, Groenewald D, Guthrie AJ.Between 2004 and 2006, 145 African horse sickness viruses (AHSV) were isolated from blood and organ samples submitted from South Africa to the Faculty of Veterinary Science, University of Pretoria. All nine serotypes were represented, with a range of 3-60 isolates per serotype. The RNA small segment 10 (S10) nucleotide sequences of these isolates were determined and the phylogeny investigated. AHSV, bluetongue virus (BTV) and equine encephalosis virus (EEV) all formed monophyletic groups and BTV was genetically closer to AHSV than EEV. This study confirmed the presence of three distinct S10 ph...
Kriegshäuser G, Deutz A, Kuechler E, Skern T, Lussy H, Nowotny N.Equine rhinitis viruses (ERVs) are the causative agents of mild to severe upper respiratory infections in horses worldwide. Immunologically, four serotypes of ERVs have been identified. Equine rhinitis A virus (ERAV) and Equine rhinitis B virus 1 (ERBV1) are the most frequent serotypes in Europe. Both viruses have a broad host range in cultured cells with ERAV being able to infect humans. Since there is neither information on the seroprevalence of ERAV and ERBV1 in Austria nor on the zoonotic potential of ERBV1, we investigated 200 horse and 137 veterinary sera for the presence of neutralizing...
Yasunaga S, Maeda K, Matsumura T, Kai K, Iwata H, Inoue T.Recently, a type-specific ELISA using equine herpesvirus type 1 (EHV-1) and type 4 (EHV-4) glycoprotein Gs (gGs) was developed by Crabb and Studdert [1993]. To investigate the dissemination of EHV-1 and -4 among horses in Japan, we applied their ELISA as suitable for discriminating between EHV-1 and -4 infections serologically. Type-specificity of the ELISA was confirmed by using paired sera of infected horses with either EHV-1 or -4. Application of the ELISA to sera collected before and after the winter season of 1995-1996 from 80 racehorses revealed that 30 horses showed significant antibody...
Paweska JT, Venter GJ.Field-collected Culicoides species (Diptera: Ceratopogonidae) were fed on horse blood-virus mixtures containing one of the six serotypes of equine encephalosis virus (EEV1 to EEV6). The virus mean titres in the bloodmeals varied between 6.1 and 7.0 log10TCID50/mL. Of 19 Culicoides species assayed after 10 days extrinsic incubation at 23.5 degrees C, five yielded the challenge virus, namely Culicoides (Avaritia) imicola Kieffer (EEV1-6), C. (A.) bolitinos Meiswinkel (EEV1, 2, 4, 6), C. (Meijerehelea) leucostictus Kiefer (EEV1, 2), C. (Culicoides) magnus Colaço (EEV1) and C. (Hoffmania) zuluens...
Malalana F, Blundell RJ, Pinchbeck GL, Mcgowan CM.Equine recurrent uveitis (ERU) is a common cause of ocular pain and blindness in horses. Leptospira spp. have been commonly implicated in the pathophysiology of ERU in mainland Europe and the USA. No recent studies have been carried out in the UK, but Leptospira is reported not to be a major factor in the aetiology of ERU in the UK. Objective: To establish the prevalence of Leptospira-associated ERU in the UK and to identify the serovars involved in these cases; to compare serum vs. aqueous humour antibody levels in cases and controls in order to confirm the diagnosis of Leptospira-associated ...
Donahue JM, Smith BJ, Poonacha KB, Donahoe JK, Rigsby CL.In this study, the prevalence of leptospira-induced abortions/stillbirths for the past 3 foaling seasons (1991-1993) was determined, and fetal tissues and/or the mare's urine from positive cases were cultured in an attempt to isolate and identify the leptospira serovars responsible for the abortions. The sensitivity and specificity of the primary diagnostic tests, the fluorescent antibody test (FAT) and the microscopic agglutination test (MAT), used for the diagnosis of leptospirosis were also determined. For the 3 years, 74 (3.3%) of 2,264 abortion/stillborn submissions were diagnosed as lept...
Alexander AJ, Bailey E, Woodward JG.Fourteen Standardbred horses homozygous for one of six equine lymphocyte antigen (ELA) specificities (A1, A3, A4, A5, A6, or A10) were analyzed by Southern blot hybridization using DNA probes derived from the mouse major histocompatibility complex (MHC). Total genomic DNA from peripheral lymphocytes was digested with the restriction enzymes Hind III, Pvu II, or Eco RI. Twenty-three to thirty-three bands were generated for individual horses with the class I cDNA probe. The resulting band patterns revealed 12-14 nonpolymorphic fragments, which is consistent with the highly conserved Qa/Tla genes...
Li D, Mattoo P, Keller JE.Hyperimmune monovalent antitoxins to botulinum neurotoxin serotypes A and B have been produced by immunizing horses with newly developed formalin toxoids. After primary immunization, horses developed acceptable prophylactic antibody titers (1-5 IU/mL). Three horses received additional toxoid booster injections to induce hyperimmune antibody titers with antitoxin-A and antitoxin-B titers reaching peaks of approximately 2000 IU/mL and 150-625 IU/mL, respectively. Titers were quantified throughout the process by antigen-capture ELISA and by in-vivo neutralization. ELISA titers and neutralization ...
Hainisch EK, Abel-Reichwald H, Shafti-Keramat S, Pratscher B, Corteggio A, Borzacchiello G, Wetzig M, Jindra C, Tichy A, Kirnbauer R, Brandt S.We have previously shown that immunization of horses with bovine papillomavirus type 1 (BPV1) L1 virus-like particles (VLPs) is safe and highly immunogenic and that BPV1 and bovine papillomavirus type 2 (BPV2) are closely related serotypes. Here we evaluated the protective potential of a BPV1 L1 VLP vaccine against experimental BPV1 and BPV2 challenge and studied the safety and immunogenicity of a bivalent equine papillomavirus type 2 (EcPV2)/BPV1 L1 VLP vaccine. Fourteen healthy horses were immunized with BPV1 L1 VLPs (100 µg per injection) plus adjuvant on days 0 and 28, while seven remai...
Howell PG, Nurton JP, Nel D, Lourens CW, Guthrie AJ.Cohorts of yearlings were sampled over a period of 6 years in a retrospective serological survey to establish the annual prevalence of serotype specific antibody to equine encephalosis virus on Thoroughbred stud farms distributed within defined geographical regions of South Africa. Seasonal seroprevalence varied between 3.6% and 34.7%, revealing both single and multiple serotype infections in an individual yearling. During the course of this study serotypes 1 and 6 were most frequently and extensively identified while the remaining serotypes 2, 3, 4, 5 and 7 were all identified as sporadic and...
Weyer CT, Joone C, Lourens CW, Monyai MS, Koekemoer O, Grewar JD, van Schalkwyk A, Majiwa PO, MacLachlan NJ, Guthrie AJ.Blood samples collected as part of routine diagnostic investigations from South African horses with clinical signs suggestive of African horse sickness (AHS) were subjected to analysis with an AHS virus (AHSV) group specific reverse transcription quantitative polymerase chain reaction (AHSV RT-qPCR) assay and virus isolation (VI) with subsequent serotyping by plaque inhibition (PI) assays using AHSV serotype-specific antisera. Blood samples that tested positive by AHSV RT-qPCR were then selected for analysis using AHSV type specific RT-qPCR (AHSV TS RT-qPCR) assays. The TS RT-qPCR assays were ...
Burrage TG, Laegreid WW.African horsesickness (AHS) is a serious, non-contagious disease of horses and other solipeds caused by an arthropod-borne orbivirus of the family Reoviridae. In horses, AHS causes three distinct clinicopathologic syndromes, the pulmonary, cardiac and fever forms of the disease. Recent work has shown that the primary determinant of the form of disease expressed by naive horses is the virulence of the virus inoculum. Horses which recover from AHS exhibit solid humoral immunity against homologous challenge. Protective antibodies appear to be directed towards neutralizing epitopes on AHS virus VP...
Fagre AC, Mayo CE, Pabilonia KL, Landolt GA.Detection of is difficult as a result of intermittent leptospiruria and brief leptospiremia. Hence, diagnosis relies heavily on serologic testing, the reference method of which is the microscopic agglutination test (MAT). In horses, clinical leptospirosis has been associated with abortion, recurrent uveitis, and sporadic cases of hepatic and renal disease. Little information exists on the seroprevalence of antibodies to in equids in the United States; past nationwide studies suggest that the seroprevalence in some areas is as high as 77% (reciprocal titer ≥ 100). We tested sera from 124 ...
Smith AW, Vedros NA, Akers TG, Gilmartin WG.In a 5-year study (1972-1977) of microbial agents isolated from both clinically normal and diseased marine mammals, it was shown that certain disease agents are widespread in a diversity of ocean populations and that some are also transmissible to a number of terrestrial mammal species. Leptospira interrogans serovar pomona has been isolated repeatedly from 2 species of pinnipeds (Zalophus californianus califonianus and Callorhinus ursinus). Some of the more important bacterial pathogens for land mammals that were isolated from wild marine mammals are Pseudomonas mallei, Clostridium chauvoei, ...
Phalen DN, Drew ML, Simpson B, Roset K, Dubose K, Mora M.Cattle Egrets have a worldwide distribution, feed in proximity to cattle and other domestic animals, and often nest in large colonies in urban woodlots. Over a 3-yr period, nestlings from five Cattle Egret colonies from Central Texas, USA, were surveyed for salmonellosis. Prevalence of infection ranged from 29% to 95%. Seventeen Salmonella enterica subsp. enterica serotypes were isolated, of which the 4,5,12:i-monophasic serotype predominated in cultures of both the digestive tract and pooled spleen and liver. Of 11 4,5,12:i-monophasic isolates phage typed, eight were determinate type 193. The...
Crafford JE, Lourens CW, Smit TK, Gardner IA, MacLachlan NJ, Guthrie AJ.African horse sickness (AHS) is typically a highly fatal disease in susceptible horses and vaccination is currently used to prevent the occurrence of disease in endemic areas. Similarly, vaccination has been central to the control of incursions of African horse sickness virus (AHSV) into previously unaffected areas and will likely play a significant role in any future incursions. Horses in the AHSV-infected area in South Africa are vaccinated annually with a live-attenuated (modified-live virus [MLV]) vaccine, which includes a cocktail of serotypes 1, 3, 4 (bottle 1) and 2, 6-8 (bottle 2) deli...
Lelli R, Molini U, Ronchi GF, Rossi E, Franchi P, Ulisse S, Armillotta G, Capista S, Khaiseb S, Di Ventura M, Pini A.African horse sickness (AHS) is a non-contagious viral disease of solipeds transmitted by Culicoides. The disease is endemic in most African countries. Past experience has shown that Italy is a country exposed to emerging infectious diseases endemic to Africa; an incursion of AHS virus together with the widespread presence of Culicoides vectors could be the cause of a serious epidemic emergency. A live attenuated vaccine containing seven of the nine viral serotypes, serotype 5 and 9 are excluded, is commercially available from Onderstepoort Biological Products. However, the use of live vaccine...
Holland RE, Schmidt A, Sriranganathan N, Grimes SD, Wilson RA, Brown CM, Walker RD.Serotype, biotype, antibiogram, hemolysin production, fimbrial hemagglutinins, select toxin genes (STb, STaP, LT, slt1 and slt2) and the attaching effacing (eae) gene were determined for 99 foal strains of E. coli. E. coli from diarrheic and normal foals could not be distinguished by serotype, biotype, or antibiogram. Differences (P < or = 0.05) were observed in hemolysin production (11.5% vs 0%) and the expression of mannose-resistant hemagglutinins (23% vs 13%) among E. coli from diarrheic and healthy foals, respectively. Three of the E. coli strains from diarrheic foals were positive wit...
Mead DG, Ramberg FB, Maré CJ.In previous experiments we have demonstrated that colonized and wild black flies are competent laboratory vectors of different Mexican and Western USA isolates of vesicular stomatitis virus, serotype New Jersey (VSV-NJ). We have recently demonstrated biological VSV-NJ transmission by black flies using animal models. In the study described here, we tested the vector competence of colonized and wild black flies for the vesicular stomatitis virus, serotype Indiana (VSV-IN). A 1998 equine isolate was used. After a 10 day incubation period, saliva from experimentally infected Simulium vittatum and ...
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 ...
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...
Arent Z, Gilmore C, Brem S, Ellis WA.Strains of Leptospira interrogans belonging to two very closely related serovars – Bratislava and Muenchen – are known to cause widespread infection of the horse population in many parts of the world. Conventional serological typing of isolates has been unable to differentiate between wildlife, pig, dog and possibly horse maintained isolates and therefore has been unable to provide further insight into their diversity and the relationship between them. Twenty-one such European isolates of serovar Bratislava and Muenchen were examined by restriction endonuclease analysis and multiple-locus ...
Martínez-Torrecuadrada JL, Langeveld JP, Venteo A, Sanz A, Dalsgaard K, Hamilton WD, Meloen RH, Casal JI.African horse sickness virus (AHSV) causes a fatal disease in horses. The virus capsid is composed of a double protein layer, the outermost of which is formed by two proteins: VP2 and VP5. VP2 is known to determine the serotype of the virus and to contain the neutralizing epitopes. The biological function of VP5, the other component of the capsid, is unknown. In this report, AHSV VP5, expressed in insect cells alone or together with VP2, was able to induce AHSV-specific neutralizing antibodies. Moreover, two VP5-specific monoclonal antibodies (MAbs) that were able to neutralize the virus in a ...
Laviada MD, Babín M, Dominguez J, Sánchez-Vizcaíno JM.A sandwich enzyme-linked immunsorbent assay (ELISA) for rapid detection of African horsesickness virus (AHSV) in infected spleens or cell culture supernatant was developed. This method uses two monoclonal antibodies (MAbs) which recognize two non-overlapping epitopes of the major core protein (VP7) to coat the solid phase, and one labeled with biotin as second antibody. This ELISA was evaluated for its ability to detect AHSV in infected spleens resulting in a sensitivity of 97.4% and a specificity of 100% compared with virus isolation in cell culture, and can be used for the detection of the n...
Ohta C, Hoshi A, Goto H, Tsunoda N, Tagami M, Akita H.Epizootiological and virological studies were conducted on foal diarrhea occurring in 3 foal-raising locations in a light horse farm from March to July, 1987. At the first location, although 27 (75%) of 36 foals had developed diarrhea, the isolation rate of rotavirus (RV) was low (5/14 feces, 36%). Many of the foals had the disease as early as 23 days after birth. At the second and third locations, 21 (27%) of 78 foals and 41 (76%) of 54 foals were affected with diarrhea. Isolation rates of RV were 90% (20/22 feces) and 100% (26/26 feces), respectively. The diseased cases were observed through...
Paweska JT, Prinsloo S, Venter GJ.The oral susceptibility of livestock-associated South African Culicoides midges (Diptera: Ceratopogonidae) to infection with the tissue culture-attenuated vaccine strains of African horse sickness virus (AHSV) currently in use is reported. Field-collected Culicoides were fed on horse blood-virus mixtures each containing one of the seven serotype-specific vaccine strains of AHSV, namely serotypes 1, 2, 3, 4, 6, 7 and 8. The mean titres of virus in the bloodmeals for the seven vaccine strains were between 6.8 and 7.6 log10TCID50/mL. All females (n = 3262) that survived 10 days extrinsic incubati...
Melnick JL, Schmidt NJ, Hampil B, Ho HH.This paper describes the preparation of seven combination pools of equine antisera, designated J though P, for identification of 19 coxsackievirus A immunotypes. Each pool is composed of 4 to 6 antisera; the serotypes included are A1-6, 8, 10-15, and 17-22. These pools, unlike the previously prepared A-H enterovirus pools, were lyophilized from volumes of 0.5 ml dispensed into 5-ml vials, and when rehydrated with 5 ml of diluent provide 50-antibody-unit material ready for use in identification tests without further dilution. Procedures for using the antiserum pools are given, and guidance is p...
Zientara S, Sailleau C, Moulay S, Cruciere C.A single tube reverse transcription-polymerase chain reaction (RT-PCR) method for detection of African horse sickness virus (AHSV) in splenic tissues from infected horses is described. Double stranded RNA was extracted from infected organs of horses and used to produce complementary DNA (cDNA) with the two primers selected for the PCR. The 1179 bp amplified product (the segment 7 which encodes for VP 7), detected by electrophoresis on agarose gel and ethidium bromide staining, was hydrolysed with eight restriction endonucleases for characterization of the AHSV. The sensitivity of this method i...
Hamond C, Martins G, Bremont S, Medeiros MA, Bourhy P, Lilenbaum W.A strain of Leptospira kirschneri (serogroup Grippotyphosa) was cultured from urine of a mare post-abortion in Brazil and characterized by serogrouping, multiple-locus variable-number tandem repeat analysis, PGFE, and sequencing of genes rrs and secY. Strains of L. kirschneri have apparently never been recovered from horses in tropical area, only in Europe and USA. Knowledge of local epidemiology is important to interpret genetic profiles of leptospires circulating in an area.
Morse EV, Duncan MA, Page EA, Fessler JF.Salmonellosis in Equidae is a serious global problem. The prevalence may range from 0.36% to 27%. Probably 5% to 10% of the equine population in the U.S. is or has been infected. Over 40 serotypes of Salmonella have been cultured from Equidae. S. typhimurium (66.31%), S. enteritidis (9.6%), S. newport (5.16%) and S. heidelberg (4.89%) have been the most common equine isolates. The clinical and bacteriological studies of 23 naturally occurring infections in a large veterinary hospital were studied. Nine patients were infected with S. typhimurium, 8 with S. anatum, 1 with S. newport, 4 with dual...
