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.
Aida H, Foreman JH, Ochi A, Takizawa Y, Yamanaka T.Equine piroplasmosis is an infectious disease caused by Babesia caballi and Theileria equi. A competition horse that had been imported to the Equestrian Park for the Tokyo 2020 Olympic Games and had a fever over 40°C and severe anemia was diagnosed with equine piroplasmosis by blood smear and direct polymerase chain reaction (PCR) tests for Theileria equi. Treatment with protozoan anthelmintics and whole blood transfusion diminished the fever, improved the anemia, and allowed the horse to return home safely. Preparation for routine cases of this infection should include the development of a s...
subsp. is a rare etiologic agent of bacterial meningitis in humans. The disease is a zoonotic infection and is transmitted through close contact with domestic animals, mainly horses. Only 37 cases of meningitis have been reported in the literature until July 2023. The aim of this study is to present a rare clinical case of -related meningitis in a human immunodeficiency virus (HIV)-positive patient and analyze the literature. We present a 23-year-old horse breeder patient with advanced immunosuppression due to acquired immunodeficiency syndrome (AIDS) and meningitis, admitted at the Clinic...
Rivolta AA, Bujold AR, Wilmarth PA, Phinney BS, Navelski JP, Horohov DW, Sanz MG.Neonates have different cellular composition in their bronchoalveolar lavage fluid (BALF) when compared to foals and adult horses; however, little is known about the non-cellular components of BALF. The objective of this study was to determine the proteomic composition of BALF in neonatal horses and to compare it to that of foals and adult horses. Bronchoalveolar lavage fluid samples of seven neonates (< 1 week age), four 5 to 7-week-old foals, and six adult horses were collected. Quantitative proteomics of the fluid was performed using tandem mass tag labeling followed by high resolution l...
Jin Y, Li W, Ba X, Li Y, Wang Y, Zhang H, Li Z, Zhou J.Zoonotic diseases pose a significant threat to public health. Chlamydia, as an intracellular pathogen, can colonize the intestinal tract of humans and animals, changing the gut microbiota. However, only a few studies have evaluated alterations in the gut microbiota of horses infected with Chlamydia. Therefore, this study aimed to investigate gut microbiota and serum biochemical indicators in horses with Chlamydial infection (IG) and healthy horses (HG). Fecal and blood samples were collected from 16 horses (IG: 10; HG: 6) before morning feeding for the determination of gut microbiota and serum...
Trápaga MR, Poester VR, Mousquer MA, de Souza RP, Rafael LA, Bonel J, Melo AM, Reis AG, de Faria RO, Stevens DA, Nogueira CEW, Xavier MO.Aspergillosis is an uncommon disease in horses, but it can be fatal. We report two cases of systemic aspergillosis in foals that occurred in a short period in the same region of southern Brazil. In addition, a literature review of similar cases was also performed. Risk factors were attributed to an immunodepression by primary enterocolitis and corticosteroid treatment, the damage in the epithelium, and multiple antibacterial treatments, which allowed local fungal proliferation, tissue invasion and spread of infection, leading to death. Since the antemortem diagnosis of aspergillosis in foals i...
Bustos CP, Retamar G, Leiva R, Frosth S, Ivanissevich A, Demarchi ME, Walsh S, Frykberg L, Guss B, Mesplet M, Waller A.Streptococcus dysgalactiae subsp. equisimilis (Sde) is a commensal bacterium of horses that causes opportunistic infections. The aim of the work was to study genotypic and phenotypic properties of the Sde strain related to equine neonatal mastitis. Sde was isolated from an 8 day-old filly and sequenced for genome analysis, antibiotic susceptibility tests and virulence factor (VF) assays. The Sde strain presented the novel emm-subtype stC839.12 and the novel multilocus-sequence type ST-670, which belonged to a specific equine genotype group. Although no specific genotypic mechanisms related to ...
Alshammari A, Gattan HS, Marzok M, Salem M, Al-Jabr OA, Selim A.Fasciola hepatica is a trematode parasite that affects wide range of mammalian hosts including horses. There are no epidemiological data on fasciolosis in Egyptian horses. Hence, the present study aimed to evaluate the seroprevalence of F. hepatica in horses using ELISA as well as assess the associated risk factors for fasciolosis infection. A total of 400 sera samples of horses from three Egyptian governorates were examined. The overall seroprevalence rate in horses was 13% and the disease was more prevalent in Qalubia (14.17%) and Gharbia (16.67%) which are located at Nile Delta. The likelih...
Thomas BA, Saylor RK, Taylor ZP, Rhodes DVL.Strangles is a highly contagious upper respiratory infection of equids that is globally distributed. The causative agent of strangles, subspecies , can be spread through indirect contact with infected fomites, and studies have shown this microbe to live well in varying environmental conditions. The purpose of this study was to analyze strangles case numbers across the United States of America from 2018 to 2022 to investigate potential temporal or weather patterns associated with outbreaks. Diagnosed case records were obtained from the Equine Disease Communication Center, university databases,...
Maggi R, De Paolis L, De Santis D, Vellone VG, De Ciucis CG, Fruscione F, Mazzocco K, Ghelardi A, Marruchella G, Razzuoli E.Papillomas are benign epithelial lesions protruding on the epithelial surfaces as finger-like or warty projections. These lesions are often caused by papillomavirus (PV) infection. Congenital papillomas have been reported in foals. However, to date, no evidence of PV infection has been provided. In the present paper, we describe the main clinical-pathological features of a congenital papilloma observed in a foal. In addition, biomolecular tests demonstrated BPV1 infection in the case under study. Such data stimulate further investigations, even on archived samples, aiming to clarifying the eti...
Tallon RE, Whitt B, Bladon BM.Monitoring antibiotic usage is an important part of tackling antimicrobial resistance. The use of computerised records for monitoring has been previously described in the equine sector but there is currently no consensus on metrics used to report usage. Objective: To document antibiotic use in equine practices in the United Kingdom over a 10-year period using commercially available practice management software. Methods: Retrospective survey. Methods: A custom antibiotic usage report was created using Eclipse® practice management software. Participating practices were given instructions on how...
Torres LEC, Florez CO, Oliveira JG, Vieira GD, Ribeiro IS, Keller KM, Leme FOP, Fantini P, Maranhão RPA.In equine ophthalmology, ulcerative keratitis is among the most common conditions and, in general, arises as a consequence of some trauma suffered. Secondarily, subsequent contamination by pathogenic or resident bacteria of the horse's ocular microbiota may have undesirable consequences. Under physiological conditions, the normal microbiota coexists with the immune status of the host, serving as a barrier, ensuring the health of the ocular surface, and inhibiting the proliferation of pathogens. However, in the imbalance of immune barriers, the normal microbiota can become pathogenic and lead t...
Cui C, Li L, Wu L, Wang X, Zheng Y, Wang F, Wei H, Peng J.A healthy intestine plays an important role in the growth and development of farm animals. In small intestine, Paneth cells are well known for their regulation of intestinal microbiota and intestinal stem cells (ISCs). Although there has been a lot of studies and reviews on human and murine Paneth cells under intestinal homeostasis or disorders, little is known about Paneth cells in farm animals. Most farm animals possess Paneth cells in their small intestine, as identified by various staining methods, and Paneth cells of various livestock species exhibit noticeable differences in cell shape, ...
Stummer M, Frisch V, Glitz F, Hinney B, Spergser J, Krücken J, Diekmann I, Dimmel K, Riedel C, Cavalleri JV, Rümenapf T, Joachim A, Lyrakis M....Acute abdominal pain (colic) is one of the major equine health threats worldwide and often necessitates intensive veterinary medical care and surgical intervention. Equine coronavirus (ECoV) infections can cause colic in horses but are rarely considered as a differential diagnosis. To determine the frequency of otherwise undetected ECoV infections in horses with acute colic, fresh fecal samples of 105 horses with acute colic and 36 healthy control horses were screened for viruses belonging to the species by RT-PCR as well as for gastrointestinal helminths and bacteria commonly associated with...
Alm YH, Osterman-Lind E, Martin F, Lindfors R, Roepstorff N, Hedenström U, Fredriksson I, Halvarsson P, Tydén E.Cyathostominae are ubiquitous to grazing horses and regarded the most prevalent internal parasite in the horse. Unfortunately, decades of indiscriminate use of anthelmintic drugs have resulted in the development of resistance in cyathostomins to all currently available drug groups, the most recent being a documented lack of efficacy to the macrocyclic lactones (ML). In vivo determination of anthelmintic resistance in horses most often utilises the faecal egg count reduction test (FECRT). Further, a shortened egg reappearance period (ERP) can indicate a change in response to the applied treatme...
Nohejl T, Palkovicova J, Nesporova K, Valcek A, Lausova J, Dolejska M.The operon encoding short-chain fructooligosaccharide (scFOS) utilization enables bacteria of the family to grow and be sustained in environments where they would struggle to survive. Despite several cases of the detection of the operon in isolates of avian and equine origins, its global distribution in bacterial genomes remains unknown. The presence of the plasmid-harbored operon among resistant bacteria may promote the spread of antibiotic resistance. A collection of 11,538 antimicrobial-resistant isolates from various sources was screened for the gene encoding the scFOS transporter. O...
Uchida-Fujii E, Niwa H, Senoh M, Kato H, Kinoshita Y, Mita H, Ueno T.We encountered 34 Clostridioides difficile (C. difficile) infection (CDI) cases among Thoroughbred horses in Japan from 2010 to 2021. Among them, 79.4% (27/34) either died or were euthanised. The risk factors associated with CDI and mortality among Japanese Thoroughbred horses remain unclear. We used genetic methods to examine C. difficile strains and their relationships with prognosis. Twenty-two (64.7%) cases were hospitalised at the onset of colitis. Outcomes were balanced for hospitalisation rates at the onset of colitis. The mortality rates of cases treated with metronidazole (65.0%) were...
Spoormakers TJ, Heim C, Vermunt L, Fürst A, Rovel T.To describe clinical and imaging features and surgical treatment of equine mandibular aneurysmal bone cysts (ABCs) with β-tricalcium phosphate (TCP). Methods: 3 horses (cases 1, 2, and 3) and 1 pony (case 4) with histologically confirmed ABC. Methods: All cases had mandibular swelling with intact adjacent skin. Cases 1 to 3 had a body condition score of 3/5 and case 4 had 2/5 and showed quidding during mastication and, at oral examination, large interdental spaces and loose elements adjacent to the swelling. Radiography or CT was performed in all cases. In cases 1, 3, and 4, an expansile sept...
Semik-Gurgul E, Gurgul A, Szmatoła T.Recent publications confirmed that long non-coding RNAs (lncRNAs) perform an essential function in gene-specific transcription regulation. Nevertheless, despite its important role, lncRNA has not yet been described in equine sarcoids, the skin neoplasia of horses. Therefore, the aim of this study is to deepen the knowledge about lncRNA expression in the pathogenesis of equine sarcoids and provide new insight into the regulatory function of lncRNA in the bovine papillomavirus-dependent neoplasia of horse dermal tissues. RNA sequencing (RNA-seq) data from 12 equine sarcoid samples and the corres...
Enriquez CK, Morrow JK, Graves A, Johnson A.Equine protozoal myeloencephalitis (EPM) caused by Sarcocystis neurona remains an antemortem diagnostic challenge in some horses. Recent work suggested the use of real-time PCR (rtPCR) on cerebrospinal fluid (CSF) as a promising diagnostic tool. Objective: To evaluate the sensitivity and specificity of S. neurona rtPCR on CSF for EPM diagnosis using horses with EPM and S. neurona-seropositive horses with other neurologic conditions. Methods: Ninety-nine horses with neurologic disease that underwent complete neurologic examination, CSF collection, and, if euthanized, necropsy including the cent...
Cantatore F, Pagliara E, Marcatili M, Bertuglia A.Obtaining a healthy wound environment that is conductive to healing in horses can be challenging. Negative-pressure wound therapy (NPWT) has been employed in humans to enhance wound healing for decades. The existing evidence for the effectiveness of NPWT remains uncertain in equine medicine. The aim of this review is to investigate NPWT applications and benefits in horses. A scoping review was performed according to the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines for scoping reviews on three databases (PubMed, Web of Science-Thompson Reuters, and Wiley...
Faghihzadeh Gorji F, Sadr S, Sharifiyazdi H, Borji H.Parasitic infections pose significant threats to humans' and animals' well-being worldwide. Among these parasites, Halicephalobus spp., a genus of nematodes, has gained attention due to its ability to cause severe infections in various animal species, including horses. Objective: This study aimed to determine the prevalence of Halicephalobus spp., specifically focusing on Halicephalobus gingivalis in horses. Methods: In July 2022, a cross-sectional study was conducted in northern Iran to determine the prevalence of Halicephalobus spp. Using standard coprological techniques, 141 fecal samples f...
Bohlman T, Waddell H, Schumaker B.The occurrence of zoonotic infections following an animal exposure continues to be an important consideration for all patients, especially those within agricultural communities. Streptococcus equi subspecies equi (S. equi subsp. equi) is a bacteria known to cause a common infection called 'Strangles' in horses. This article highlights a new case of pneumonia and bacteremia in a patient caused by S. equi subsp. equi following strangles exposure in a horse. Rarely has there been reported horse to human transmission of subsp. equi. Methods: A 70-year-old woman attended a rural emergency departmen...
Lightbody KL, Austin A, Lambert PA, von Samson-Himmelstjerna G, Jürgenschellert L, Krücken J, Nielsen MK, Sallé G, Reigner F, Donnelly CG....Cyathostomins are ubiquitous equine nematodes. Infection can result in larval cyathostominosis due to mass larval emergence. Although faecal egg count (FEC) tests provide estimates of egg shedding, these correlate poorly with burden and provide no information on mucosal/luminal larvae. Previous studies describe a serum IgG(T)-based ELISA (CT3) that exhibits utility for detection of mucosal/luminal cyathostomins. Here, this ELISA is optimised/validated for commercial application using sera from horses for which burden data were available. Optimisation included addition of total IgG-based calibr...
Jondeau C, Guyonnet A, Losada A, Laloy E, Reyes-Gomez E, Le Dudal M, Chahory S.To describe a case of lipogranulomatous conjunctivitis in a horse. Methods: A client-owned 12-year-old Standardbred gelding presenting with chronic conjunctivitis and palpebral masses. Methods: Complete ophthalmic examination, surgical excision, histopathology, and bacterial culture of biopsy samples were performed. Results: Upper and lower eyelids of both eyes were affected, with multiple yellow-to-white nodules on the palpebral conjunctiva, adjacent to the eyelid margin. Nodule removal was achieved via partial tarsal plate excision. Histopathological examination revealed granulomatous inflam...
Amory H, Cesarini C, De Maré L, Loublier C, Moula N, Detilleux J, Saulmont M, Garigliany MM, Lecoq L.The objective of this retrospective study was to evaluate the clinical significance of fecal quantitative real-time polymerase chain reaction (qPCR) results when taking the cycle threshold values (Ct) into account. The study included 120 qPCR-positive fecal samples obtained from 88 hospitalized horses over a 2-year period. The mean Ct of the qPCR test was evaluated in regard to (1) clinical outcome and (2) systemic inflammatory response syndrome (SIRS) status (no SIRS, moderate SIRS, or severe SIRS) of the sampled horses. An ROC analysis was performed to establish the optimal cut-off Ct valu...
Rule EK, Boyle AG, Stefanovski D, Anis E, Linton J, Lorello O.Equine granulocytic anaplasmosis (EGA) is a common disease in adult horses, but clinical disease in foals is rarely reported. The relationship between equine maternal and neonatal antibodies to Anaplasma phagocytophilum is unclear. Objective: That mares in an endemic region would be seropositive for A. phagocytophilum and that mare and foal serum IgG concentrations for A. phagocytophilum would correlate. Additionally, we hypothesized that foal IgG concentrations for A. phagocytophilum acquired by passive immunity would decline by 6 months of age. Methods: Twenty-two healthy mare-foal pairs. ...
Amairia S, Jbeli M, Mrabet S, Jebabli LM, Gharbi M.Sarcocystis spp. and Toxoplasma gondii are two apicomplexan protozoa that infect a broad range of vertebrates, however, little is known about the infection of equids with these parasites. A total of 184 slaughtered equids from slaughterhouses of Bizerte and Tunis located in Northern Tunisia, were examined for meat infections with Sarcocystis spp. and T. gondii by PCR. The prevalence of infections with Sarcocystis spp. and T. gondii were 38% (95% CI: 31-45) and 39.7% (95% CI: 32.6-46.7), respectively. The highest prevalence of infection with Sarcocystis spp. was observed in donkeys (48.6%; 95%C...
Carossino M, Balasuriya UBR, Thieulent CJ, Barrandeguy ME, Vissani MA, Parreño V.Equine rotavirus A (ERVA) is the leading cause of diarrhea in foals, with G3P[12] and G14P[12] genotypes being the most prevalent. Recently, equine G3-like RVA was recognized as an emerging infection in children, and a group B equine rotavirus (ERVB) was identified as an emergent cause of foal diarrhea in the US. Thus, there is a need to adapt molecular diagnostic tools for improved detection and surveillance to identify emerging strains, understand their molecular epidemiology, and inform future vaccine development. We developed a quadruplex TaqMan RT-qPCR assay for differentiation of ERVA an...
Matas Riera M, Cardenas Nadal M, Martínez-Sogues L, Ferrer L.Dermatological clinical signs have been seldom reported in the literature secondary to equine leishmaniasis. This case depicts the clinical signs, treatment, and outcome of a young horse with a pink, elevated lesion on the ventromedial quadrant of the cornea. A corneal cytology was performed and revealed the presence of leishmania amastigotes reaching the diagnosis of keratitis secondary to leishmania. Surgical resection was recommended but the owner declined the procedure, and the lesion was treated with a topical antimonial for 6 weeks. The lesion reduced remarkably during the first weeks ...
Ferris RA, McCue PM, Borlee GI, Glapa KE, Martin KH, Mangalea MR, Hennet ML, Wolfe LM, Broeckling CD, Borlee BR.Bacteria in a biofilm community have increased tolerance to antimicrobial therapy. To characterize the role of biofilms in equine endometritis, six mares were inoculated with -engineered strains isolated from equine uterine infections. Following establishment of infection, the horses were euthanized and the endometrial surfaces were imaged for luminescence to localize adherent -labeled bacteria. Samples from the endometrium were collected for cytology, histopathology, carbohydrate analysis, and expression of inflammatory cytokine genes. Tissue-adherent bacteria were present in focal areas bet...
Fritz D.Positive PCR results for piroplasms were obtained on EDTA blood samples from 166 dogs and 111 horses between March 2006 and March 2008. The organisms were initially identified using common primers, followed by restriction enzyme profiles to determine the species and types of Babesia/Theileria. In 27 dogs and eight horses with positive results, the size of the specimen was insufficient to separate species/types. We identified Babesia canis canis in 105 of the 166 dogs (63%) and Theileria equi in 89 of the 111 horses (80%). Babesia caballi was also present, but rare, in only two Babesia/Theileri...
Beisel CE, Edwards JF, Dunn LL, Rice NR.Transcription of pathogenic equine infectious anemia virus (EIAV) in an acutely infected horse was examined by using the polymerase chain reaction and nucleotide sequencing. Four spliced transcripts were identified in liver tissue, in contrast to the multiplicity of alternatively spliced messages reported for in vitro-propagated human immunodeficiency virus, simian immunodeficiency virus, and, to a lesser extent, EIAV. Nucleotide sequence analysis demonstrated that three of these mRNAs encode known viral proteins: the envelope precursor, the product of the S2 open reading frame, and the regula...
Traversa D, Castagna G, von Samson-Himmelstjerna G, Meloni S, Bartolini R, Geurden T, Pearce MC, Woringer E, Besognet B, Milillo P, D'Espois M.This paper reports a survey conducted in France during 2011 to evaluate the efficacy of commonly used anthelmintics against horse cyathostomins. A total of 40 farms and 1089 horses were screened for the presence of cyathostomins. All farms but one were positive, with an overall animal infection rate of 53.7%, ranging from 9% to 83% on individual farms. On 445 horses from 30 of these farms, a faecal egg count reduction test (FECRT) was performed to evaluate the efficacy of oral formulations of fenbendazole (FBZ), pyrantel embonate (PYR), ivermectin (IVM) and moxidectin (MOX). Calculation of the...
Irvine KL, Hopkins LJ, Gangloff M, Bryant CE.TLR2 recognises bacterial lipopeptides and lipoteichoic acid, and forms heterodimers with TLR1 or TLR6. TLR2 is relatively well characterised in mice and humans, with published crystal structures of human TLR2/1/Pam3CSK4 and murine TLR2/6/Pam2CSK4. Equine TLR4 is activated by a different panel of ligands to human and murine TLR4, but less is known about species differences at TLR2. We therefore cloned equine TLR2, TLR1 and TLR6, which showed over 80% sequence identity with these receptors from other mammals, and performed a structure-function analysis. TLR2/1 and TLR2/6 from both horses and hu...
Vázquez-Morón S, Avellón A, Echevarría JE.The Lyssavirus genus includes seven species or genotypes named 1-7. Rabies genotypes correlate with geographical distribution and specific hosts. Co-circulation of different lyssaviruses, imported cases, and the presence of unknown viruses, such as Aravan, Khujand, Irkut and West Caucasian Bat Virus, make it necessary to use generic methods able to detect all lyssaviruses. Primer sequences were chosen from conserved regions in all genotypes in order to optimise a generic RT-PCR. Serial dilutions of 12 RNA extracts from all seven Lyssavirus genotypes were examined to compare the sensitivity of ...
Song SD, Barker SC, Shao R.The genus Haematopinus contains 21 species of blood-sucking lice, parasitizing both even-toed ungulates (pigs, cattle, buffalo, antelopes, camels and deer) and odd-toed ungulates (horses, donkeys and zebras). The mitochondrial genomes of the domestic pig louse, Haematopinus suis, and the wild pig louse, Haematopinus apri, have been sequenced recently; both lice have fragmented mitochondrial genomes with 37 genes on nine minichromosomes. To understand whether the composition of mitochondrial minichromosomes and the gene content and gene arrangement of each minichromosome are stable within the g...
Donadeu FX, Schauer SN.Relatively little is known about the physiological roles of microRNAs (miRNAs) during follicular development. Previous evidence from in vitro studies suggests specific roles for a subset of miRNAs, including miR-21, miR-23a, miR-145, miR-503, miR-224, miR-383, miR-378, miR-132, and miR-212, in regulating ovarian follicle development. The objective of this study was to gain insight on the involvement of these miRNAs during follicle maturation. Follicular fluid was aspirated from dominant follicles (>32 mm) during the ovulatory season (July to October) and the anovulatory season (January to M...
Leblond A, Pradier S, Pitel PH, Fortier G, Boireau P, Chadoeuf J, Sabatier P.Anaplasmosis is caused by the bacterium Anaplasma phagocytophilum and transmitted by Ixodes spp. ticks. According to some reports the disease can be introduced into disease-free zones by migrating birds. The purpose of this study was to evaluate the seroprevalence of A. phagocytophilum in horses in the Camargue. Data concerning 424 horses were gathered and the sera were tested for A. phagocytophilum and for piroplasmoses using an enzyme-linked immunosorbent assay and a complement fixation test, respectively. The seroprevalence rates were 11.3 % for A. phagocytophilum, 64.4 % for Theileria equi...
Paillot R, Kydd JH, Sindle T, Hannant D, Edlund Toulemonde C, Audonnet JC, Minke JM, Daly JM.In horses, equine influenza virus (EIV) is a leading cause of respiratory disease. Conventional inactivated vaccines induce a short-lived immune response. By comparison, natural infection confers a long-term immunity to re-infection. An aim of new equine influenza vaccines is to more closely mimic natural infection in order to achieve a better quality of immunity. A new live recombinant vaccine derived from the canarypox virus vector and expressing haemagglutinin genes of EIV (subtype H3N8) has been developed. Stimulation of the immune system was studied after immunisation with this canarypox-...
Abdelgawad A, Hermes R, Damiani A, Lamglait B, Czirják GÁ, East M, Aschenborn O, Wenker C, Kasem S, Osterrieder N, Greenwood AD.Equine herpesvirus type 1 (EHV-1) causes respiratory disorders and abortion in equids while EHV-1 regularly causes equine herpesvirus myeloencephalopathy (EHM), a stroke-like syndrome following endothelial cell infection in horses. Both EHV-1 and EHV-9 infections of non-definitive hosts often result in neuronal infection and high case fatality rates. Hence, EHV-1 and EHV-9 are somewhat unusual herpesviruses and lack strict host specificity, and the true extent of their host ranges have remained unclear. In order to determine the seroprevalence of EHV-1 and EHV-9, a sensitive and specific pepti...
Raabe ML, Issel CJ, Cook SJ, Cook RF, Woodson B, Montelaro RC.We have previously reported that immunization of ponies with a baculovirus-expressed recombinant surface unit envelope protein (rgp90) for equine infectious anemia virus (EIAV) resulted in enhancement of disease symptoms and virus replication in 4 of 4 vaccine recipients subjected to a heterologous virus challenge (rpg90 I vaccine trial) (Wang et al., 1994). To extend these studies of EIAV vaccine enhancement, two additional and independent rgp90 vaccine trials (rgp90 II and rgp90 III) were performed. Combined, a total of 13 ponies were immunized with the rgp90 immunogen using our standard vac...
Haussler KK.The clinical assessment of pain is subjective; therefore, variations exist between practitioners in their ability to identify and localize pain. Due to differing interpretations of the signs or severity of pain equine practitioners may assign varying levels of clinical significance and treatment options. There is a critical need to develop better tools to qualify and quantify pain in horses. Palpation is the most common method to detect local tenderness or sensitivity. To quantify this applied pressure, pressure algometry has been used to gradually apply pressure over specified landmarks until...
Lyons ET, Tolliver SC, Collins SS.Critical tests were carried out in 2008 in four yearling horses (H-2, H-4, H-10, and H-11) born and raised together on a farm (MC) in Central Kentucky. These horses were treated intraorally with ivermectin paste at the dose rate of 200 microg/kg. The main interest was to try and determine more precisely, from posttreatment (PT) worm count data, the current activity of ivermectin against small strongyles in a horse herd. These horses had been treated repeatedly with this compound and counts of small strongyle eggs per gram of feces (EPGs) of these parasites have been returning sooner than previ...
Reif JS, Webb PA, Monath TP, Emerson JK, Poland JD, Kemp GE, Cholas G.In 1982-1983, an epizootic of vesicular stomatitis occurred in the western United States. Veterinarians, research workers, and regulatory personnel who were exposed to vesicular stomatitis virus were examined for patterns of human infection and prevalence of vesicular stomatitis New Jersey serotype neutralizing antibody. Insight into the mechanism of transmission was sought by comparing activities of antibody-positive and antibody-negative persons. A statistically significant risk factor was a history of infected animals sneezing in the face of serosurvey participants. Elevated odds ratios wer...
Hagos A, Goddeeris BM, Yilkal K, Alemu T, Fikru R, Yacob HT, Feseha G, Claes F.Trypanocidal sensitivity studies were conducted to assess the efficacy of Diminazene diaceturate (Diminasan) and Bis (aminoethylthio) 4-melaminophenylarsine dihydrochloride (Cymelarsan) against Trypanosoma equiperdum (isolated from two mares with chronic cases of dourine) 713/943 and 834/940 Dodola strains in experimentally infected mice and horses. Diminasan at doses from 3.5 mg/kg to 28 mg/kg and Cymelarsan at doses of 0.25 mg/kg and 0.5 mg/kg body weight failed to cure any of the mice, indicating a clear dose dependent relationship in the mean time of relapse observed in mice. Indeed, mice ...
Hasebe R, Sasaki M, Sawa H, Wada R, Umemura T, Kimura T.We investigated the mechanism by which equine herpesvirus-1 (EHV-1) enters primary cultured equine brain microvascular endothelial cells (EBMECs) and equine dermis (E. Derm) cells. EHV-1 colocalized with caveolin in EBMECs and the infection was greatly reduced by the expression of a dominant negative form of equine caveolin-1 (ecavY14F), suggesting that EHV-1 enters EBMECs via caveolar endocytosis. EHV-1 entry into E. Derm cells was significantly reduced by ATP depletion and treatments with lysosomotropic agents. Enveloped virions were detected from E. Derm cells by infectious virus recovery a...
Elton D, Bryant N.Despite the availability of vaccines, equine influenza virus (EIV) continues to pose a threat to the racing industry. The virus spreads rapidly in unprotected populations and large scale outbreaks, such as those in South Africa in 2003 and Australia in 2007, can cost billions of pounds. Like other influenza viruses, EIV undergoes antigenic variation, enabling it to evade antibodies generated against previous infection or vaccination. The UK has an active surveillance programme to monitor antigenic drift and participates in an international collaboration with other countries in Europe, Japan an...
Holden VR, Harty RN, Yalamanchili RR, O'Callaghan DJ.The complete nucleotide sequence of the inverted repeat component (IR; 12,776 bp each) of the genome of equine herpesvirus type 1 (EHV-1) has been determined. Transcription analyses have revealed that the EHV-1 IR sequence encodes at least 6 genes. In this report, we present the DNA sequence and transcriptional characterization of a gene (IR3) that maps entirely within the IR sequences. The IR3 open reading frame (ORF) is located between nucleotides (nt) 6123-6411 of the IR sequence and possesses an ORF of 95 amino acids. Interestingly, this ORF does not show homology to any known herpesvirus ...
Smith AD, Panickar KS, Urban JF, Dawson HD.Vitamins and minerals (micronutrients) play an important role in regulating and shaping an immune response. Deficiencies generally result in inadequate or dysregulated cellular activity and cytokine expression, thereby affecting the immune response. Decreased levels of natural killer, granulocyte, and phagocytic cell activity and T and B cell proliferation and trafficking are associated with inadequate levels of micronutrients, as well as increased susceptibility to various adverse health conditions, including inflammatory disorders, infection, and altered vaccine efficacy. In addition, most s...
Guerrero-Carvajal F, Bravo-Barriga D, Martín-Cuervo M, Aguilera-Sepúlveda P, Ferraguti M, Jiménez-Clavero MÁ, Llorente F, Alonso JM, Frontera E.West Nile virus (WNV) is a mosquito-borne emerging virus in Europe with capacity to cause neurological complications such as encephalitis or meningoencephalitis in humans, birds or equids. In Spain, WNV is actively circulating in mosquitoes, birds and horses in different regions, but never has been deeply studied in Extremadura. Therefore, the aim of this study was to evaluate the seroprevalence of WNV in equids of those areas and to analyse the risk factors associated with exposure to the virus. A total of 199 out of 725 equids presented antibodies against WNV by competition ELISA (27.45%), w...
Henderson BE, Chappell WA, Johnston JG, Sudia WD.Henderson, B. E., W. A. Chappell, J. G. Johnston, Jr. and W. D. Sudia (CDC, Atlanta, Ga. 30333). Experimental Infection of horses with three strains of Venezuelan equine encephalomyelitis virus. I. Clinical and virological studies. Amer J Epidem 93: 194–205, 1971.—Clinical effect, viremias and antibody responses were compared in horses inoculated with the following strains of Venezuelan equine encephalomyelitis (VEE) virus: Fe3-7C, isolated from Culex (Melano-conion) spp. mosquitoes collected In 1963 in the Florida Everglades; TC-83, the Fort Detrick live, attenuated vaccine strain; and GJ...
Garton NJ, Gilleron M, Brando T, Dan HH, Giguère S, Puzo G, Prescott JF, Sutcliffe IC.Rhodococcus equi is a major cause of foal morbidity and mortality. We have investigated the presence of lipoglycan in this organism as closely related bacteria, notably Mycobacterium tuberculosis, produce lipoarabinomannans (LAM) that may play multiple roles as virulence determinants. The lipoglycan was structurally characterized by gas chromatography-mass spectrometry following permethylation, capillary electrophoresis after chemical degradation, and (1)H and (31)P and two-dimensional heteronuclear nuclear magnetic resonance studies. Key structural features of the lipoglycan are a linear alph...
Wagnerová P, Sak B, McEvoy J, Rost M, Matysiak AP, Ježková J, Kváč M.Faecal samples were collected from 352 horses on 23 farms operating under six different management systems in the Czech Republic and Poland during 2011 and 2012. Farms were selected without previous knowledge of parasitological status. All faecal samples were screened for Cryptosporidium spp. presence using microscopy, following aniline-carbol-methyl violet staining and PCR analysis of the small-subunit (SSU) rRNA and the 60-kDa glycoprotein (gp60) genes. Cryptosporidium muris-positive samples were additionally genotyped at four minisatellite markers: MS1 (encoding a hypothetical protein), MS2...
Aurich C, Spergser J.This study investigated effects of bacteria from the genital tract of horses and the effect of gentamicin in semen extender on spermatozoal function in cooled-stored stallion semen. Semen was collected from healthy stallions and processed with a milk-based extender with or without gentamicin (1g/l). Pseudomonas (Ps.) aeruginosa, Staphylococcus (St.) aureus, Streptococcus (Sc.) equi subsp. equi (Sc. equi), Sc. equi subsp. zooepidemicus (Sc. zooepidemicus), Sc. dysgalactiae subsp. equisimilis (Sc. equisimilis) or culture medium alone (control) were added. Immediately after addition of bacteria a...
Long A, Nolen-Walston R.Serum amyloid A (SAA) is a marker of inflammation and infection in the horse that can be assessed in the field, with rapid and marked changes seen following initiation of an inflammatory stimulus. This quality of SAA also makes its clinical use challenging, because even small inflammatory conditions can cause large changes in SAA levels. Review of the current literature provides guidelines for responses of SAA to various conditions, which can be applied to specific clinical cases. The practitioner is encouraged to use SAA in conjunction with physical examination and other diagnostic modalities...
Halbert ND, Reitzel RA, Martens RJ, Cohen ND.To evaluate sensitivity and specificity of a multiplex polymerase chain reaction (PCR) assay for simultaneous detection of Rhodococcus equi and differentiation of strains that contain the virulence-associated gene (vapA) from strains that do not. Methods: 187 isolates of R equi from equine and nonequine tissue and environmental specimens and 27 isolates of bacterial species genetically or morphologically similar to R equi. Methods: The multiplex PCR assay included 3 gene targets: a universal 311-bp bacterial 16S ribosomal RNA amplicon (positive internal control), a 959-bp R equi-specific targe...
