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.
Muller S, Grzybowski M, Sager H, Bornand V, Brehm W.This report describes a case of nodular posthitis caused by Halicephalobus gingivalis in a 24-year-old warmblood horse. Macroscopic examination revealed a multinodular, partially ulcerated mass on the external lamina of the prepuce. Nematode migration from unfixed biopsy material in phosphate-buffered saline revealed adult nematodes with the typical morphological features of H. gingivalis: distinctive rhabditiform oesophagus with corpus, isthmus and bulb and the dorsoflexed ovary. The main histopathological features consisted of submucosal confluent granulomatous foci containing cross- and tan...
Traversa D, Fichi G, Campigli M, Rondolotti A, Iorio R, Proudman CJ, Pellegrini D, Perrucci S.Anoplocephala perfoliata (Cestoda, Cyclophyllidea), the commonest intestinal tapeworm of horses, can cause colic, intussusceptions, ileal impactions and intestinal perforations. Common diagnostic techniques for A. perfoliata infection, i.e. coprology and serology, show inherent limitations in terms of sensitivity and specificity and new approaches are thus required. Hence, the present study compared the reliability of coprological, serological (i.e. ELISA) and molecular (i.e. nested PCR) methods in detecting A. perfoliata infection in naturally infected horses and in horses treated with a comb...
Milinovich GJ, Burrell PC, Pollitt CC, Bouvet A, Trott DJ.Four Gram-positive, catalase-negative, coccoid-shaped isolates were obtained from the caecum and rectum of horses with oligofructose-induced equine laminitis. Phenotypic and phylogenetic studies were performed on these isolates. Initial biochemical profiling assigned two of the isolates to Streptococcus bovis. The other two isolates, however, could not be assigned conclusively on the basis of their biochemical profiles. Gene sequence analysis demonstrated that the four new isolates were related most closely to Streptococcus suis based on the 16S rRNA gene and to Streptococcus orisratti based o...
Varcasia A, Garippa G, Pipia AP, Scala A, Brianti E, Giannetto S, Battelli G, Poglayen G, Micagni G.Between March 2003 and February 2007, the livers and the lungs of 2,231 horses from various Italian regions were examined for cystic echinococcosis presence at the time of slaughter. Hydatid cysts were found in six horses, namely four from Sardinia, one from Sicily, and one from Tuscany. The location, number, morphology, and fertility of the cysts found were determined. DNA was extracted from the germinal layers and protoscoleces of the fertile cysts and polymerase chain reactions (PCR) were performed in order to strain type DNA isolates for reduced nicotinamide adenine dinucleotide dehydrogen...
Scotty NC, Brooks DE, Schuman Rose CD.To evaluate the in vitro efficacy of an ophthalmic drug combination against common corneal pathogens of horses. Methods: Representative isolates of 3 bacterial and 2 fungal corneal pathogens of horses. Methods: Pathogens were subjected to minimum inhibitory concentration (MIC) testing of a drug combination that consisted of equal volumes of natamycin 3.33%, tobramycin 0.3%, cefazolin 5.5%, and equine serum. Proteinase inhibitory activity of the drug combination was assessed by use of a fluorescence microplate assay with gelatin and collagen I as substrates. The MICs of the drug combination wer...
Bell SA, Pusterla N, Balasuriya UB, Mapes SM, Nyberg NL, MacLachlan NJ.Equids are commonly infected by herpesviruses, but isolation of herpesviruses from mules has apparently not been previously reported. Furthermore, the genomic relationships among the various equid herpesviruses are poorly characterized. We describe the isolation and preliminary characterization of a mule gammaherpesvirus tentatively identified as asinine herpesvirus-2 (AHV-2; also designated equid herpesvirus-7 (EHV-7)) from the nasal secretions (NS) of a healthy mule in northern California. The virus was initially identified by transmission electron microscopic examination of lysates of cell ...
Elitsur E, Marsh AE, Reed SM, Dubey JP, Oglesbee MJ, Murphy JE, Saville WJ.Sarcocystis neurona is the most important cause of equine protozoal myeloencephalitis (EPM), a neurologic disease of the horse. In the present work, the kinetics of S. neurona invasion is determined in the equine model. Six ponies were orally inoculated with 250 x 10(6) S. neurona sporocysts via nasogastric intubation and killed on days 1, 2, 3, 5, 7, and 9 postinoculation (PI). At necropsy, tissue samples were examined for S. neurona infection. The parasite was isolated from the mesenteric lymph nodes at 1, 2, and 7 days PI; the liver at 2, 5, and 7 days PI; and the lungs at 5, 7, and 9 days ...
Mansfield LS, Mehler S, Nelson K, Elsheikha HM, Murphy AJ, Knust B, Tanhauser SM, Gearhart PM, Rossano MG, Bowman DD, Schott HC, Patterson JS.We tested the hypothesis that brown-headed cowbirds (Molothrus ater) harbor Sarcocystis neurona, the agent of equine protozoal myeloencephalitis (EPM), and act as intermediate hosts for this parasite. In summer 1999, wild caught brown-headed cowbirds were collected and necropsied to determine infection rate with Sarcocystis spp. by macroscopic inspection. Seven of 381 (1.8%) birds had grossly visible sarcocysts in leg muscles with none in breast muscles. Histopathology revealed two classes of sarcocysts in leg muscles, thin-walled and thick-walled suggesting two species. Electron microscopy sh...
Venter GJ, Paweska JT.Previously reported virus recovery rates from Culicoides (Avaritia) imicola Kieffer and Culicoides (Avaritia) bolitinos Meiswinkel (Diptera, Ceratopogonidae) orally infected with vaccine strain of African horse sickness virus serotype 7 (AHSV-7) were compared with results obtained from concurrently conducted oral infections with five recent AHSV-7 isolates from naturally infected horses from various localities in South Africa. Culicoides were fed sheep bloods spiked with 10(7.6) TCID(50)/mL of a live-attenuated vaccine strain AHSV-7, and with five field isolates in which virus titre in the blo...
Horta MC, Labruna MB, Pinter A, Linardi PM, Schumaker TT.This study investigated rickettsial infection in animals, humans, ticks, and fleas collected in five areas of the state of São Paulo. Eight flea species (Adoratopsylla antiquorum antiquorum, Ctenocephalides felis felis, Polygenis atopus, Polygenis rimatus, Polygenis roberti roberti, Polygenis tripus, Rhopalopsyllus lugubris, and Rhopalopsyllus lutzi lutzi), and five tick species (Amblyomma aureolatum, Amblyomma cajennense, Amblyomma dubitatum, Ixodes loricatus, and Rhipicephalus sanguineus) were collected from dogs, cats, and opossums. Rickettsia felis was the only rickettsia found infecting ...
Allen GP, Bolin DC, Bryant U, Carter CN, Giles RC, Harrison LR, Hong CB, Jackson CB, Poonacha K, Wharton R, Williams NM.An emerging problem of equine herpesvirus-1 (EHV-1) infection in horses in the USA is a high-mortality myeloencephalopathy that commonly occurs where large numbers of horses are stabled. EHV-1 isolates recovered from recent neurological outbreaks represent a mutant virus strain that possesses enhanced neuropathogenicity. A central question of EHV-1 myeloencephalopathy is the latency carriage rate for these mutants of EHV-1 in USA horse populations. Objective: To estimate the prevalence of neuropathogenic strains of EHV-1 as latent infections in the Thoroughbred broodmare population of central ...
Divers TJ, Irby NL, Mohammed HO, Schwark WS.Information on antibiotic concentrations in the equine eye following systemic therapy is limited. Reports that Leptospira spp. are frequently present in the eyes of horses with recurrent uveitis, emphasises a need for studies on ocular concentrations of specific antibiotics. Objective: 1) Enrofloxacin, administered i.v. at 7.5 mg/kg bwt q. 24 h, results in aqueous humour concentrations greater than the reported minimum inhibitory concentration (MIC) for Leptospira pomona. 2) Aqueous humour paracentesis sufficiently disrupts the blood-aqueous humour barrier (BAB) to cause an increase in aqueous...
Ashrafi GH, Piuko K, Burden F, Yuan Z, Gault EA, Müller M, Trawford A, Reid SWJ, Nasir L, Campo MS.Equine sarcoids are fibroblastic skin tumours affecting equids worldwide. While the pathogenesis is not entirely understood, infection with bovine papillomavirus (BPV) type 1 (and less commonly type 2) has been implicated as a major factor in the disease process. Sarcoids very seldom regress and in fact often recrudesce following therapy. Nothing is known about the immune response of the equine host to BPV. Given that the viral genes are expressed in sarcoids, it is reasonable to assume that vaccination of animals against the expressed viral proteins would lead to the induction of an immune re...
Scorpio DG, Leutenegger C, Berger J, Barat N, Madigan JE, Dumler JS.Anaplasma phagocytophilum causes human granulocytic anaplasmosis by inducing immunopathologic responses. Its immunodominant Msp2 protein is encoded by a family of >100 paralogs. Msp2 (msp2) expression modulates in the absence of immune pressure, and prolonged in vitro passage modulates in vivo virulence. Because programmed MSP2 expression occurs in Anaplasma marginale, we hypothesized a similar event in A. phagocytophilum in vivo, with specific Msp2 expression triggering immunopathologic injury or clinical manifestations of disease. We examined msp2 transcripts in 11 B6 mice and 6 horses inocu...
Hornok S, Genchi C, Bazzocchi C, Fok E, Farkas R.Peripheral blood samples were collected randomly from 195 horses in various parts of Hungary, and the presence of microfilariae was evaluated by the Knott technique. On the basis of morphological identification 18 of the horses (9.2 per cent) were infected with Setaria equina, and the infection was confirmed in 10 animals by pcr and sequencing. The level of microfilaraemia was between 1 and 1138 larvae in 2 ml of blood. There was no correlation between the time of sampling or the sex of the animals (stallions versus mares) and the prevalence of infection, but the prevalence decreased with age....
Rashid HB, Chaudhry M, Rashid H, Pervez K, Khan MA, Mahmood AK.The present work was conducted to study the comparative efficacy of two anti-protozoan (babesicidal) drugs on the recovery and health of horses. A total of 80 horses, showing typical clinical symptoms of the disease, were selected for this study; the presence of babesiosis was confirmed through blood smear examination. These animals were divided into two groups i.e. A and B. Horses of Group A, were treated with diminazene diaceturate, while horses of Group B were treated with diminazene aceturate. Efficacy of the drugs was determined by the reversal of clinical signs and a negative blood smear...
Valentine BA, Löhr CV.Three horses with colic, clinical evidence of endotoxaemia and high serum activities of creatine kinase and aspartate aminotransferase were examined postmortem. The horses were diagnosed with severe ulcerative colitis, pyloric ulceration and stenosis with colonic sand impaction, and colonic obstruction due to faecaliths. There was no gross or histological evidence of muscle trauma. Their semimembranosus muscles had scattered acute to subacute segmental necrosis of the myofibres, suggestive of endotoxin-induced muscle injury.
Kjaer LN, Lungholt MM, Nielsen MK, Olsen SN, Maddox-Hyttel C.Increased knowledge is needed to assist in the interpretation of presently available diagnostic techniques for infection by the tapeworm Anoplocephala perfoliata in horses. Objective: The suggested cut-off level of an A. perfoliata specific ELISA may not adequately reflect the actual infection level. Hence, faecal egg counts may be a more useful diagnostic test for individual horses than previously reported. Methods: Eighty-four horses admitted for slaughter at a Danish abattoir were examined for the presence of A. perfoliata. The number of tapeworms, their stage of development and gross patho...
Williamson A, Rogers CW, Firth EC.To identify feeding and management variables associated with variation in faecal pH within a population of intensively managed Thoroughbred racehorses in New Zealand. Methods: A cross-sectional survey was conducted of 16 racehorse trainers in the North Island of New Zealand. Interviews were conducted at the trainers' stables to obtain information on feeding and management of horses, and faecal samples were collected and faecal pH measured. Results: Ninety-seven percent of the horses surveyed were confined in an area or=12 h/day. Trainer's age, number of years they had trained horses, age and g...
Akagami M, Shibahara T, Yoshiga T, Tanaka N, Yaguchi Y, Onuki T, Kondo T, Yamanaka T, Kubo M.A ten-year-old Shetland pony gelding showed low appetite, ataxia, peculiar swaying, clouding of consciousness, and ultimately died. At necropsy, multiple coalescing granulomatous foci were detected in the kidneys, and small necrotic lesions were found in the cerebellum. Histologic examination of the renal tissue sections revealed extensive granuloma, and Halicephalobus gingivalis-like nematodes were seen. Similar nematodes were found in the granulomatous or necrotic lesions of the renal lymph nodes and cerebellum, and were also frequently detected in cerebrospinal meningovascular lesions. Morp...
Niwa H, Anzai T, Hobo S.Contagious equine metritis (CEM) is a highly contagious bacterial venereal disease of horses caused by Taylorella equigenitalis. CEM-PCR is a semi-nested PCR method for detecting this bacterium. Although this technique is regarded as a sensitive diagnostic method for CEM, there are risks of it generating false positive and false negative results. In this study, we constructed a recombinant plasmid (CEM-POS) as reaction control to assure adequate PCR reaction and prevent false positive results caused by contamination of the reaction control in routine CEM-PCR examinations. CEM-POS was construct...
Adam EN, Southwood LL.To determine historical, physical, and microbiologic findings in horses with limb cellulitis and identify factors associated with short- and long-term outcome. Methods: Retrospective case series. Methods: 44 horses with limb cellulitis. Methods: Information obtained from medical records included use, history, affected limb, diagnostic procedures, treatment, and short-term outcome. Long-term follow-up information was obtained by means of a telephone survey. Results: Twenty-four horses had primary cellulitis, and 18 of the 24 (75%) had a hind limb affected. Results of microbiologic culture were ...
Suzuki K, Matsui Y, Miura Y, Sentsui H.Equine coronavirus (ECoV) was first isolated from a diarrheic foal and was found genetically similar to group II coronaviruses. However, its pathological characteristics were not adequately investigated. In our preliminary in vitro investigation, ECoV-induced cell death was observed in bovine kidney-derived MDBK cells. Based on this finding, we investigated whether the ECoV-induced CPE was apoptosis. Following ECoV infection, MDBK cells showed morphological changes such as cell rounding and detachment from the culture surface. Moreover, syncytium formation was observed as the other type of cyt...
Brindley MA, Maury W.Entry of wild-type lentivirus equine infectious anemia virus (EIAV) into cells requires a low-pH step. This low-pH constraint implicates endocytosis in EIAV entry. To identify the endocytic pathway involved in EIAV entry, we examined the entry requirements for EIAV into two different cells: equine dermal (ED) cells and primary equine endothelial cells. We investigated the entry mechanism of several strains of EIAV and found that both macrophage-tropic and tissue culture-adapted strains utilize clathrin-coated pits for entry. In contrast, a superinfecting strain of EIAV, EIAV(vMA-1c), utilizes ...
Wagner B, Glaser A, Hillegas JM, Erb H, Gold C, Freer H.West Nile virus (WNV) is a zoonotic pathogen of global importance. In horses with neurological signs, detection of WNV-specific immunoglobulin M (IgM) in serum is widely used to identify clinical cases of WNV encephalitis. Here, we describe the development of two monoclonal antibodies (mAbs) to equine IgM which were used in a WNV IgM-specific enzyme-linked immunosorbent assay (ELISA). Their performance was compared to an established assay based on polyclonal anti-IgM. Check test serum samples from the National Veterinary Service Laboratory (NVSL) were used to evaluate the performance of the th...
Buckley T, McManamon E, Stanbridge S.This study sought to determine whether an increase in resistance of Rhodococcus equi to the antibiotics rifampin and erythromycin occurred over a 10-year period. This was carried out by the use of E test strips for rifampin and erythromycin to determine the MIC (minimum inhibitory concentration) values of Rhodococcus equi to this combination of antibiotics.The findings of this study indicated that there was an increase in resistance of Rhodococcus equi to rifampin and erythromycin over the 10-year period. The MIC for rifampin increased from 0.081 μg/ml in 1996 to 0.187 μg/ml in 2006 and from...
Morita H, Shiratori C, Murakami M, Takami H, Kato Y, Endo A, Nakajima F, Takagi M, Akita H, Okada S, Masaoka T.Two strains, KBL13(T) and GBL13, were isolated as one of intestinal lactobacilli from the faecal specimens from different thoroughbreds of the same farm where they were born in Hokkaido, Japan. They were Gram-positive, facultatively anaerobic, catalase-negative, non-spore-forming and non-motile rods. KBL13(T) and GBL13 homofermentatively metabolize glucose, and produce lactate as the sole final product from glucose. The 16S rRNA gene sequence, DNA-DNA hybridization, DNA G+C content and biochemical characterization indicated that these two strains, KBL13(T) and GBL13, belong to the same species...
Liu L, Castillo-Olivares J, Davis-Poynter NJ, Baule C, Xia H, Belák S.Samples from horses experimentally infected with the "large plaque variant (LP3A+)" of equine arteritis virus were analysed. These included 182 nasal swabs collected from day 1 to 14 post-infection (p.i.), and 21 virus isolates obtained from white blood cells of animals that showed a prolonged viraemia between days 30 to 72 p.i. In order to determine the genetic stability of the virus and particularly to characterise the genetic variants found during the prolonged viraemia, partial sequences of open reading frame 5 (ORF5) encoding glycoprotein 5 (GP5) were generated. Viruses with amino acid su...
Dini P, Norris J, Ali HE, Loux SC, Carossino M, Esteller-Vico A, Bailey E, Kalbfleisch T, Daels P, Ball BA.Increasing evidence suggests that overlapping genes are much more common in eukaryotic genomes than previously thought. These different-strand overlapping genes are potential sense-antisense (SAS) pairs, which might have regulatory effects on each other. In the present study, we identified the SAS loci in the equine genome using previously generated stranded, paired-end RNA sequencing data from the equine chorioallantois. We identified a total of 1261 overlapping loci. The ratio of the number of overlapping regions to chromosomal length was numerically higher on chromosome 11 followed by chrom...
Cutler TJ, MacKay RJ, Ginn PE, Greiner EC, Porter R, Yowell CA, Dame JB.Equine protozoal myeloencephalitis (EPM) is a debilitating neurologic disease of the horse. The causative agent. Sarcocystis neurona, has been suggested to be synonymous with Sarcocystis falcatula, implying a role for birds as intermediate hosts. To test this hypothesis, opossums (Didelphis virginiana) were fed muscles containing S. falcatula sarcocysts from naturally infected brown-headed cowbirds (Molothrus ater). Ten horses were tested extensively to ensure no previous exposure to S. neurona and were quarantined for 14 days, and then 5 of the horses were each administered 10(6) S. falcatula...
Heuzenroeder MW, Barton MD, Vanniasinkam T, Phumoonna T.The aim of this chapter is to provide a strategy for mapping linear antibody epitopes of protein antigens in order to discover candidates for vaccines or diagnostic tests. A set of overlapping peptides was designed and synthesised based upon a known amino acid sequence of the target protein, virulence-associated protein A (VapA) of the bacterium Rhodococcus equi, an important pulmonary pathogen in foals.The peptides were biotinylated and used in an ELISA to screen immune sera from foals. These biotinylated peptides were coated directly onto micro titre plates that had been pre-coated with Neut...
Rushton JO, Kolodziejek J, Nell B, Weissenböck H, Nowotny N.The role of equid γ-herpesviruses on ocular surface diseases has been disputed, because the diagnosis is usually based on clinical symptoms and detection of viral DNA from samples obtained from live animals. Objective: To describe the clinical course, results of polymerase chain reaction (PCR) analysis, in situ hybridisation, cell culture and pathohistological findings of select cases in a presumed outbreak of herpesvirus infection in a group of 15 Icelandic horses. Methods: Case series. Methods: Pooled ocular and nasal swabs and peripheral blood mononuclear cells of horses diagnosed clinica...
Bade D, Portis E, Keane C, Hallberg J, Bryson L, Sweeney M, Boner P.In vitro activity of ceftiofur and six other antimicrobial agents was evaluated against 79 Streptococcus equi subsp zooepidemicus isolates collected from horses with respiratory disease in Europe during 2007 and 2008. In addition, the in vitro activity of ceftiofur and other antimicrobial drugs was assessed against 59 S. equi subsp zooepidemicus and 49 S. equi subsp equi isolates collected by veterinary diagnostic laboratories in Europe from 2002 to 2006. The lowest concentration of ceftiofur that inhibited the growth of 90% of the isolates (MIC90) was 0.12 microg/ml, with the Clinical Laborat...
Feary DJ, Abraham S, Woolford L, Trott DJ.A 6-year-old Arabian mare had a 4-week history of a subcutaneous mass (15 × 15 cm) at the base of the neck, cranial and distal to the prescapular lymph node on the right side. The mass was solid and painful on deep palpation. Ultrasonographic examination showed a soft-tissue abscess. Purulent aspirate was submitted for bacterial culture, which showed a moderate growth of an Actinomyces species. 16S rRNA gene sequencing was performed for definitive identification. Gene sequencing demonstrated close nucleotide homology with A. denticolens. Prolonged therapeutic management resulted in resolu...
The Journal of protozoologyAugust 1, 1980
Volume 27, Issue 3 288-292 doi: 10.1111/j.1550-7408.1980.tb04259.x
Simpson CF, Mayhew IG.Equine protozoal myeloencephalitis (EPM) was diagnosed in 10 horses. By electron microscopy, schizonts were found in intact host cells of the spinal cords or, more frequently, free in the extracellular spaces. Developmental stages of schizonts differed morphologically, and the late stage of schizogony was characterized by endopolygeny. These findings permitted tentative identification of the protozoon as a Sarcocystis sp. Free merozoites were present in the extracellular spaces or in cells of the spinal cord. Pericytes of capillaries were most frequently parasitized by merozoites were present ...
Baraúna RA, Ramos RTJ, Veras AAO, de Sá PHCG, Guimarães LC, das Graças DA, Carneiro AR, Edman JM, Spier SJ, Azevedo V, Silva A.The genomes of four strains (MB11, MB14, MB30, and MB66) of the species Corynebacterium pseudotuberculosis biovar equi were sequenced on the Ion Torrent PGM platform, completely assembled, and their gene content and structure were analyzed. The strains were isolated from horses with distinct signs of infection, including ulcerative lymphangitis, external abscesses on the chest, or internal abscesses on the liver, kidneys, and lungs. The average size of the genomes was 2.3 Mbp, with 2169 (Strain MB11) to 2235 (Strain MB14) predicted coding sequences (CDSs). An optical map of the MB11 strain gen...
Mula P, Pilo C, Solinas C, Pipia AP, Varcasia A, Francisco I, Arias MS, Paz Silva A, Sánchez-Andrade R, Morrondo P, Díez-Baños P, Scala A.From January to December 2008, 265 horses slaughtered in Sardinia (Italy) were examined for the presence of Rhinoestrus spp. (Diptera: Oestridae) through the examination of the nasal cavities and pharynges. Larvae were detected in 49% of the horses, with a mean intensity of infestation of 16.09 and abundance of 7.95. A total of 2108 larvae were collected, 66% of which were classified in first instar (L1), 22% in second instar (L2) and 12% in third instar (L3). The most frequent localization of larvae was the ethmoid, while the less one the larynx. According to the dynamics of Rhinoestrus larva...
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...
Pikalo J, Sattler T, Eichinger M, Loitsch A, Sun H, Schmoll F, Schusser GF.Aim of the study was to detect antibodies and potential risk factors for an infec- tion with Leptospira in horses in Middle Germany. Serum samples of 314 horses were examined retrospectively by microscopic agglutination test for the presence of antibodies against eight Leptospira serovars. In total, 17.2% (n = 54) of the horses were positive for one or more of the serovars analyzed. The most prevalent serovar was lcterohaemorrhagiae (11.1%), followed by serovar Bratislava (9.6 %) and Grippotyphosa (1.9%). Mares showed a significantly higher occurrence of antibodies (p < 0.05) than geldings ...
Samoilowa S, Giessler KS, Torres CEM, Hussey GS, Allum A, Fux R, Jerke C, Kiupel M, Matiasek K, Sledge DG, Goehring LS.Equid herpesvirus-1 (EHV-1) causes respiratory disease, abortion and myeloencephalopathy in horses worldwide. As member of the , latency is key to EHV-1 epidemiology. EHV-1 latent infection has been detected in the trigeminal ganglion (TG), respiratory associated lymphoid tissue (RALT) and peripheral blood mononuclear cells (PBMC) but additional locations are likely. The aim of this study was to investigate the distribution of viral DNA throughout the equine body. Twenty-five horses divided into three groups were experimentally infected via intranasal instillation with one of three EHV-1 virus...
Horin P, Sabakova K, Futas J, Vychodilova L, Necesankova M.In previous work, we found significant associations of horse polymorphic microsatellite and immunity-related (IR) gene markers with Rhodococcus equi infection of foals. Here, a statistically significant association between a single nucleotide polymorphism (SNP) within the interleukin 7 receptor-encoding gene (IL7R) with high R. equi burden in transtracheal aspirates was found (Fisher's F = 0.043, odds ratio: 8.00, 95% confidence interval: 1.127-56.795). Further positional and/or functional candidate genes investigated TLR2, IL13, IL17A, IL28R, TACE/ADAM 17 and GBP1, were not associated with in...
Egbe-Nwiyi TN, Paul BT, Cornelius AC.This study aimed to investigate the prevalence and intensity of nematode infection among slaughtered donkeys in Kaltungo, Nigeria. Methods: A total of 72 fecal samples were examined by salt flotation and the modified McMaster fecal egg count technique to morphologically identify nematodes eggs and determine their egg per gram (EPG) outputs. Results: Out of a total of 72 (100%) donkeys sampled, 36 (50%) tested positive, but the prevalence of nematodes was independent of the age, sex, and breed of donkeys (p>0.05). Among the four species of nematodes identified in single and mixed infections,...
Clark EG, Turner AS, Boysen BG, Rouse BT.A 1-month-old Arabian foal with signs of central nervous system disease was found to have combined (B- and T-lymphocyte) immunodeficiency. The foal died in spite of intensive antibiotic therapy. At necropsy, generalized lymphoid hypoplasia and acute necrotizing and granulomatous inflammation of the brain, heart, and adrenal glands were found. In addition, there were spinal meningitis and focal hepatic necrosis. Listeria monocytogenes was isolated on primary culture from the brain.
López-Álvarez MR, Salze M, Cenier A, Robinson C, Paillot R, Waller AS.Streptococcus equi subsp. equi (S. equi) is the causative agent of strangles, one of the most frequently diagnosed infectious diseases of horses worldwide. Phospholipase A toxins (PLA) cleave phospholipid molecules at position sn-2 contributing to the production of leukotrienes that are important inflammatory mediators. Two homologous phospholipases, SlaA and SlaB are encoded by the S. equi genome suggesting that PLA toxins may contribute to its pathogenicity. Here we report the immunogenicity and role of PLA toxins during natural and experimental infection of horses with S. equi. The levels o...
Hoane JS, Morrow JK, Saville WJ, Dubey JP, Granstrom DE, Howe DK.Sarcocystis neurona is the primary causative agent of equine protozoal myeloencephalitis (EPM), a common neurologic disease of horses in the Americas. We have developed a set of enzyme-linked immunosorbent assays (ELISAs) based on the four major surface antigens of S. neurona (SnSAGs) to analyze the equine antibody response to S. neurona. The SnSAG ELISAs were optimized and standardized with a sample set of 36 equine sera that had been characterized by Western blotting against total S. neurona parasite antigen, the current gold standard for S. neurona serology. The recombinant SnSAG2 (rSnSAG2)...
Mendoza L, Alfaro AA, Villalobos J.A 5-year-old, female saddle horse developed a tumoral mass anterolaterally on the metacarpal region of its right front leg. Histopathological study showed hyaline, aseptate, broad hyphae in the sequestered coral-like necrotic masses. Radiographs revealed an extensive osteomyelitis with disorganized bone proliferation of the metacarpal bones, as well as exostosis of the distal radius and the proximal and distal row of carpal bones. The etiologic agent was detected histologically, isolated in culture and identified as Pythium insidiosum. Serological tests were positive. Immunotherapy was applied...
Lu Z, Sarkar S, Zhang J, Balasuriya UB.Equine arteritis virus (EAV), the causative agent of equine viral arteritis, has relatively broad cell tropism in vitro. In horses, EAV primarily replicates in macrophages and endothelial cells of small blood vessels. Until now, neither the cellular receptor(s) nor the mechanism(s) of virus attachment and entry have been determined for this virus. In this study, we investigated the effect of heparin on EAV infection in equine endothelial cells (EECs). Heparin, but not other glycosaminoglycans, could reduce EAV infection up to 93 %. Sequence analysis of the EAV E minor envelope protein reveale...
Murase H, Sakai S, Kusano K, Hobo S, Nambo Y.Zinc is one of the essential microelements involved in the regulation of enzyme activity, as well as metabolism of nucleic acid and proteins. There have been few reports on equine serum zinc concentrations during the training period, and little is known about the relationship between zinc levels and diseases in horses. In this study, we measured serum zinc levels in healthy Thoroughbred racehorses, as well as in other horses, under general disease or training conditions. The reference value for serum zinc levels in Thoroughbred horses was 41-79 μg/dl. There were no differences in serum zinc l...
Pusterla N, Sanchez-Migallon Guzman D, Vannucci FA, Mapes S, White A, DiFrancesco M, Gebhart C.The aim of this study was to investigate whether feces from rabbits experimentally infected with Lawsonia intracellularis were infectious to foals. Two rabbits were infected with L. intracellularis, while two rabbits served as controls. Eight foals received daily feces from either the infected or the control rabbits. All rabbits and foals were monitored daily for clinical signs for the entire study period (21days for rabbits, 42days for foals). Feces and blood were collected for the PCR detection of L. intracellularis and serologic analysis, respectively. None of the infected rabbits or foals ...
Cappelli K, Ciucis CG, Mecocci S, Nervo T, Crescio MI, Pepe M, Gialletti R, Pietrucci D, Migone LF, Turco S, Mechelli L, Passamonti F, Drago C....Equine Papillomavirus 2 (EcPV2) is responsible for squamous cell carcinomas (eSCCs) of external genitalia of both male and female horses. However, few studies report the EcPV2 prevalence among healthy horses. Currently, the lack of these data does not permit identifying at-risk populations and, thus, developing screening protocols aimed at the early detection of the infection, as for humans. The aim of our study was to estimate the genoprevalence of EcPV2 in clinically healthy horses in Italy and to evaluate their innate immune response. For this purpose, penile and vulvar swabs of 234 healthy...
Afonso AC, Sousa M, Pinto AR, Cotovio M, Simões M, Saavedra MJ.As in human medicine, in veterinary medicine, chronic wounds are often related to polymicrobial infections and the presence of a biofilm, which compromises the effectiveness of therapeutic approaches. In this study, a Lusitano mare presented a 21-day-old chronic wound that was only being treated with an antiseptic. A swab sample was collected, and three isolates of Staphylococcus aureus and one of Pseudomonas aeruginosa were isolated. S. aureus did not show resistance to a panel of antibiotics. However, the P. aeruginosa isolate showed a resistance profile to carbapenems and fluoroquinolones, ...
Tazumi A, Maeda Y, Buckley T, Millar B, Goldsmith C, Dooley J, Elborn J, Matsuda M, Moore J.Clinical isolates (n = 63) of Pseudomonas aeruginosa obtained from various sites in 63 horses were compared using ERIC2 RAPD PCR to determine their genetic relatedness. Resulting banding patterns (n = 24 genotypes) showed a high degree of genetic heterogeneity amongst all isolates examined, indicating a relative non-clonal relationship between isolates from these patients, employing this genotyping technique. This study characterised 63 clinical isolates into 24 distinct genotypes, with the largest cluster (genotype E) accounting for 10/63 (15.9%) of the isolates. ERIC2 RAPD PCR proved to be a...
Fjordbakk CT, Arroyo LG, Hewson J.A retrospective study of 63 horses diagnosed with limb cellulitis between 1994 and 2005 was conducted. They all had an acute onset of painful, generalised limb swelling, and a clinical diagnosis of limb cellulitis was made by the attending clinician. None of the horses had more than one limb affected. Hindlimbs were significantly more often affected than the forelimbs (P<0.05). Thoroughbreds were significantly over-represented compared with the general distribution of breeds examined at the hospital. Blunt limb trauma, limb surgery and limb injections were associated with the cellulitis in mos...
Kirisawa R, Toishi Y, Hashimoto H, Tsunoda N.An equine foamy virus (EFV) was isolated for the first time in Japan from peripheral blood mononuclear cells of a broodmare that showed wobbler syndrome after surgery for intestinal volvulus and the isolate was designated as EFVeca_LM. Complete nucleotide sequences of EFVeca_LM were determined. Nucleotide sequence analysis of the long terminal repeat (LTR) region, and genes revealed that EFVeca_LM and the EFV reference strain had 97.2% to 99.1% identities. For a sero-epidemiological survey, indirect immunofluorescent antibody tests were carried out using EFVeca_LM-infected cells as an antige...
Firth EC, Klein WR, Nouws JF, Wensing T.Single doses of sodium ampicillin (10 mg/kg) and kanamycin sulfate (5 mg/kg) were administered intramuscularly (i.m.) separately, and then together, to five pony mares. The plasma antibiotic concentration-time curves were constructed. The pharmacokinetic parameters of the antibiotics given separately were not altered by concurrent administration. Four of the five pony mares were then given the i.m. kanamycin/ampicillin combination 4 h after acute synovitis and fever had been induced by injection of lipopolysaccharide into the left intercarpal joint. The plasma concentration-time curves and the...
Shields E, Seiden-Long I, Massie S, Passante S, Leguillette R.Cardiac troponin-I assays have been validated in horses.'High-sensitivity' cardiac troponin assays are now the standard in human cardiology. Objective: Appropriately validate the'high-sensitivity' cardiac Troponin-T (hscTnT) assay for clinical use in horses, establish reference intervals, determine the biological variation, and demonstrate assay utility in selected clinical cases. Methods: Analytical validation of the Roche hscTnT assay included within- and between-run precision, linear dose response, limit of quantitation (LoQ), stability, and comparison with cTn-I (iSTAT). Reference interval...
Rodríguez-Bertos A, Corchero J, Castaño M, Peña L, Luzón M, Gómez-Bautista M, Meana A.The pathological alterations caused by Anoplocephala perfoliata in the ileocaecal junction of 28 equids slaughtered in an abattoir in Madrid (Central Spain) are described. The lesions were scored in grades based on the intensity of the damage and were related to the tapeworm number observed. The first grade (grade I) of alterations consisted of a slight enteritis associated with focal erosions observed in 43% of parasitized animals with low parasitic burden (1-26 tapeworms). The second grade (grade II) was a focal pseudomembranous enteritis, present in the ileocaecal junctions of 36% infected ...
Kumar S, Kumar Y, Malhotra DV, Dhar S, Nichani AK.Serial dilution and single dilution enzyme linked immunosorbent assays (ELISA) were standardised and their sensitivity and specificity were compared for serodiagnosis of Babesia equi infection. The antibody titres of 24 donkey sera of known identity were determined separately by serial dilution ELISA using three different B. equi antigens namely whole merozoite (WM), cell membrane (CM) and high speed supernatant (HSS). The ratios of the optical density (OD) of known positive and known negative sera at different serum dilutions were calculated and termed as the positive/negative (P/N) ratio. Th...
