Infectious diseases in horses encompass a range of illnesses caused by bacteria, viruses, fungi, or parasites. These diseases can affect various systems within the equine body, leading to symptoms that range from mild discomfort to severe systemic illness. Common infectious diseases in horses include equine influenza, strangles, equine herpesvirus, and West Nile virus. These diseases can be transmitted through direct contact with infected animals, contaminated surfaces, or vectors such as insects. Understanding the mechanisms of transmission, pathogenesis, and immune response is essential for effective prevention and control. This page compiles peer-reviewed research studies and scholarly articles that explore the epidemiology, diagnosis, treatment, and management of infectious diseases in horses.
Dossa RG, Alperin DC, Garzon D, Mealey RH, Brown WC, Jervis PJ, Besra GS, Cox LR, Hines SA.α-GalCer is a potent immunomodulatory molecule that is presented to NKT cells via the CD1 antigen-presenting system. We hypothesized that when used as an adjuvant α-GalCer would induce protective immune responses against Rhodococcus equi, an important pathogen of young horses. Here we demonstrate that the equine CD1d molecule shares most features found in CD1d from other species and has a suitable lipid-binding groove for presenting glycolipids to NKT cells. However, equine CTL stimulated with α-GalCer failed to kill cells infected with R. equi, and α-GalCer did not increase killing by C...
Hawkins E, Kock R, McKeever D, Gakuya F, Musyoki C, Chege SM, Mutinda M, Kariuki E, Davidson Z, Low B, Skilton RA, Njahira MN, Wamalwa M, Maina E.The role of equine piroplasmosis as a factor in the population decline of the Grevy's zebra is not known. We determined the prevalence of Babesia caballi and Theileria equi in cograzing Grevy's zebras (Equus grevyi) and donkeys (Equus africanus asinus) in northern Kenya and identified the associated tick vectors. Blood samples were taken from 71 donkeys and 16 Grevy's zebras from March to May 2011. A nested PCR reaction using 18s ribosomal (r)RNA primers on 87 blood spots showed 72% (51/71; 95% confidence interval [CI] 60.4-81.0%) of donkeys and 100% (16/16; 95% CI, 77.3-100%) of Grevy's zebra...
Long MT.Mosquito-borne diseases affect horses worldwide. Mosquito-borne diseases generally cause encephalomyelitis in the horse and can be difficult to diagnose antemortem. In addition to general disease, and diagnostic and treatment aspects, this review article summarizes the latest information on these diseases, covering approximately the past 5 years, with a focus on new equine disease encroachments, diagnostic and vaccination aspects, and possible therapeutics on the horizon.
Cullinane M, O'Sullivan E, Collins DM, Byrne AW, More SJ.Recently, considerable international attention has been paid to the problem of unwanted horses. In Ireland, stray horses, particularly in urban areas, are a further problem. The Control of Horses Act 1996 was enacted in response to an ongoing problem of uncontrolled horses in public places. As yet, no research work has been conducted focusing on stray horses in Ireland. This paper describes horses impounded under the Act in the Munster region of Ireland during 2005-2012 and the factors influencing decisions regarding their disposal. A logistic regression model was developed to investigate fact...
Issel CJ, Cook RF, Mealey RH, Horohov DW.In the absence of an effective vaccine, the success of the test and removal approach for the control of equine infectious anemia (EIA) cannot be overstated, at least in those areas where testing has been traditionally routine. This article addresses 4 main aspects: what has been learned about EIA virus, host control of its replication, and inapparent carriers; international status regarding the control of EIA; diagnostic and laboratory investigation; and reducing the spread of blood-borne infections by veterinarians. An attempt is made to put these issues into practical contemporary perspectiv...
Balasuriya UB.Equine arteritis virus (EAV), the causative agent of equine viral arteritis (EVA), is a respiratory and reproductive disease that occurs throughout the world. EAV infection is highly species-specific and exclusively limited to members of the family Equidae, which includes horses, donkeys, mules, and zebras. EVA is an economically important disease and outbreaks could cause significant losses to the equine industry. The primary objective of this article is to summarize current understanding of EVA, specifically the disease, pathogenesis, epidemiology, host immune response, vaccination and treat...
Stringer AP.Most working equids reside in low-income countries where they have an essential role in the livelihoods of their owners. Numerous infectious diseases negatively impact the health and productivity of these animals. There are considerable technical, social-behavioral, and institutional impediments globally to reducing the burden of infectious diseases on working equids. One the greatest remaining challenges is the lack of funding for research, resulting from the low priority assigned to working equids by funding bodies. Changing the attitudes of decision makers will require data-driven advocacy,...
Howe DK, MacKay RJ, Reed SM.Equine protozoal myeloencephalitis (EPM) can be caused by either of 2 related protozoan parasites, Sarcocystis neurona and Neospora hughesi, although S. neurona is the most frequent etiologic pathogen. Horses are commonly infected, but clinical disease occurs infrequently; the factors influencing disease occurrence are not well understood. Risk factors for the development of EPM include the presence of opossums and prior stressful health-related events. Attempts to reproduce EPM experimentally have reliably induced antibody responses in challenged horses but have not consistently produced acut...
Andersson MG, Faverjon C, Vial F, Legrand L, Leblond A.In this work we propose the adoption of a statistical framework used in the evaluation of forensic evidence as a tool for evaluating and presenting circumstantial "evidence" of a disease outbreak from syndromic surveillance. The basic idea is to exploit the predicted distributions of reported cases to calculate the ratio of the likelihood of observing n cases given an ongoing outbreak over the likelihood of observing n cases given no outbreak. The likelihood ratio defines the Value of Evidence (V). Using Bayes' rule, the prior odds for an ongoing outbreak are multiplied by V to obtain the post...
Alves Ada S, Melo AL, Amorim MV, Borges AM, Gaíva E Silva L, Martins TF, Labruna MB, Aguiar DM, Pacheco RC.The aim of the study was to evaluate exposure of equids to rickettsial agents (Rickettsia rickettsii, Rickettsia parkeri, 'Candidatus Rickettsia amblyommii', Rickettsia rhipicephali, and Rickettsia bellii) and rickettsial infection in ticks of a Pantanal region of Brazil. Sera of 547 equids (500 horses and 47 donkeys) were evaluated by indirect immunofluorescence assay. In total, 665 adults and 106 nymphal pools of Amblyomma cajennense F. sensu lato, 10 Dermacentor nitens Neumann ticks, and 88 larval pools of Amblyomma sp. were tested by polymerase chain reaction (PCR). Overall, 337 (61.6%) eq...
Zohaib A, Saqib M, Beck C, Hussain MH, Lowenski S, Lecollinet S, Sial A, Asi MN, Mansoor MK, Saqalein M, Sajid MS, Ashfaq K, Muhammad G, Cao S.This study describes the first large-scale serosurvey on West Nile virus (WNV) conducted in the equine population in Pakistan. Sera were collected from 449 equids from two provinces of Pakistan during 2012-2013. Equine serum samples were screened using a commercial ELISA kit detecting antibodies against WNV and related flaviviruses. ELISA-positive samples were further investigated using virus-specific microneutralization tests (MNTs) to identify infections with Japanese encephalitis virus (JEV), WNV and tick-borne encephalitis virus (TBEV). Anti-WNV antibodies were detected in 292 samples by E...
Nielsen MK, Vidyashankar AN, Bellaw J, Gravatte HS, Cao X, Rubinson EF, Reinemeyer CR.Strongylus vulgaris is the most pathogenic helminth parasite of horses, causing verminous endarteritis with thromboembolism and infarction. A serum enzyme-linked immunosorbent assay (ELISA) has been validated for detection of antibodies to an antigen produced by migrating larvae of this parasite. The aim was to evaluate ELISA responses to anthelmintic treatment in cohorts of naturally infected horses. Fifteen healthy horses harboring patent S. vulgaris infections were turned out for communal grazing in May 2013 (day 0). On day 55, horses were ranked according to ELISA titers and randomly alloc...
Zakari FO, Ayo JO, Rekwot PI, Kawu MU.The review examines the role of blood in homeostasis, diagnosis and treatment of disease as influenced by meteorological stress factors, age, sex and physical activity of the donkeys. Haematological parameters play a crucial role in clinical diagnosis of infectious and parasitic diseases, in assessing the responses of donkeys to treatment and in prevention of diseases. The changes in blood values are important in evaluating the responses of the animals to various physiologic conditions. In conclusion, haematological values of donkeys are largely influenced by age, sex, physical factors of the ...
Duarte CG, Bonilla C, Guimarães G, Machado de Avila RA, Mendes TM, Silva W, Tintaya B, Yarleque A, Chávez-Olórtegui C.In this work, an anti-loxoscelic serum was produced by immunizing horses with a recombinant dermonecrotic protein from Loxosceles intermedia (rLiD1). Anti-rLiD1 antibodies were able to recognize different species of Loxosceles venoms by Western Blot and ELISA. The efficacy of anti-rLiD1 serum against the toxic effects of Loxosceles laeta (Peru) venom was tested, showing that anti-rLiD1 serum can neutralize those effects. This study confirms that recombinant proteins can be good candidates to replace crude venoms for antivenom production.
Finger MA, de Barros Filho IR, Leutenegger C, Estrada M, Ullmann LS, Langoni H, Kikuti M, Dornbush PT, Deconto I, Biondo AW.Cart horses are a re-emerging population employed to carry recyclable material in cities. Methods: Sixty-two horses were sampled in an endemic area of human leptospirosis. The microscopic agglutination test (MAT) and real-time polymerase chain reaction (qPCR) were performed. Results: A seropositivity of 75.8% with serovar Icterohaemorrhagiae in 80.8% of the horses was observed. Blood and urine were qPCR negative. MAT showed positive correlations with rainfall (p = 0.02) and flooding (p = 0.03). Conclusions: Although horses may be constantly exposed to Leptospira spp. in the environment mostly ...
Gaíva e Silva L, Borges AM, Villalobos EM, Lara Mdo C, Cunha EM, de Oliveira AC, Braga IA, Aguiar DM.The prevalence of antibodies against Equine Influenza Virus (EIV) was determined in 529 equines living on ranches in the municipality of Poconé, Pantanal area of Brazil, by means of the hemagglutination inhibition test, using subtype H3N8 as antigen. The distribution and possible association among positive animal and ranches were evaluated by the chi-square test, spatial autoregressive and multiple linear regression models. The prevalence of antibodies against EIV was estimated at 45.2% (95% CI 30.2 - 61.1%) with titers ranging from 20 to 1,280 HAU. Seropositive equines were found on 92.0% of...
Tabynov K, Kydyrbayev Z, Ryskeldinova S, Assanzhanova N, Kozhamkulov Y, Inkarbekov D, Sansyzbay A.To design and evaluate the safety and immunogenicity of a modified-live vaccine to prevent equine influenza virus (EIV) infection based on the novel reassortant cold-adapted strain A/HK/Otar/6:2/2010. Methods: Surface proteins (HA, NA) from the wild-type strain A/equine/Otar/764/2007 (H3N8) and internal proteins (PB2, PB1, PA, NP, M, NS) from the attenuated cold-adapted donor strain A/Hong Kong/1/68/162/35CA (H3N2) were included in the vaccine. Horses were administered 10(9.2) EID50 /mL of the modified-live vaccine or saline solution using a nasal spray. The clinical condition of the animals w...
Hamond C, Martins G, Bremont S, Medeiros MA, Bourhy P, Lilenbaum W.The purpose of the present study was to detect the presence of DNA of pathogenic Leptospira sp. in vaginal fluids of mares regarding a possible role of the sexual transmission. A total of 134 breeding mares from four troops were studied and sampling was conducted from vaginal fluids and urine for culture and PCR; and blood for serology. From the 134 serum samples tested, 59 (44%) were seroreactive, and serovar Bratislava was the most frequent (54.2%). None positive culture was obtained, but leptospiral DNA was detected by PCR (lipL32 gene) in 45 (33.5%) urine samples and 43 (32%) vaginal fluid...
Matthews JB.Anthelmintics have been applied indiscriminately to control horse nematodes for over 40 years. Three broad-spectrum anthelmintic classes are currently registered for nematode control in horses: benzimidazoles (fenbendazole, oxibendazole), tetrahydropyrimidines (pyrantel) and macrocyclic lactones (ivermectin, moxidectin). Generally, control strategies have focused on nematode egg suppression regimens that involve the frequent application of anthelmintics to all horses at intervals based on strongyle egg reappearance periods after treatment. The widespread use of such programmes has substantial...
Andoh K, Hattori S, Mahmoud HY, Takasugi M, Shimoda H, Bannai H, Tsujimura K, Matsumura T, Kondo T, Kirisawa R, Mochizuki M, Maeda K.Equine herpesvirus type 1 (EHV-1) has haemagglutination (HA) activity toward equine red blood cells (RBCs), but the identity of its haemagglutinin is unknown. To identify the haemagglutinin of EHV-1, the major glycoproteins of EHV-1 were expressed in 293T cells, and the cells or cell lysates were mixed with equine RBCs. The results showed that only EHV-1 glycoprotein C (gC)-producing cells adsorbed equine RBCs, and that the lysate of EHV-1 gC-expressing cells agglutinated equine RBCs. EHV-1 lacking gC did not show HA activity. HA activity was inhibited by monoclonal antibodies (MAbs) specific ...
Horohov DW.The modern horse, Equus caballus has historically made important contributions to the field of immunology, dating back to Emil von Behring's description of curative antibodies in equine serum over a century ago. While the horse continues to play an important role in human serotherapy, the mouse has replaced the horse as the predominant experimental animal in immunology research. Nevertheless, continuing efforts have led to an improved understanding of the equine immune response in a variety of infectious and non-infectious diseases. Based on this information, we can begin to identify specific ...
Hans A, Gaudaire D, Manuguerra JC, Leon A, Gessain A, Laugier C, Berthet N, Zientara S.This study shows that an unbiased amplification method applied to equine arteritis virus RNA significantly improves the sensitivity of the real-time reverse transcription-quantitative PCR (RT-qPCR) recommended by the World Organization for Animal Health. Twelve viral RNAs amplified using this method were hybridized on a high-density resequencing microarray for effective viral characterization.
Na W, Song M, Yeom M, Park N, Kang B, Moon H, Jeong DG, Kim JK, Song D.H3N8 equine influenza virus (EIV) causes respiratory diseases in the horse population, and it has been demonstrated that EIV can transmit into dogs owing to its availability on receptors of canine respiratory epithelial cells. Recently, we isolated H3N8 EIV from an EIV-vaccinated horse that showed symptoms of respiratory disease, and which has a partially truncated nonstructural gene (NS). However, it is not clear that the NS-truncated EIV has an ability to cross the host species barrier from horses to dogs as well. Here, we experimentally infected the NS-truncated H3N8 EIV into dogs, and moni...
Cohen ND, Bourquin JR, Bordin AI, Kuskie KR, Brake CN, Weaver KB, Liu M, Felippe MJ, Kogut MH.Neutrophils play an important role in protecting against infection. Foals have age-dependent deficiencies in neutrophil function that may contribute to their predisposition to infection. Thus, we investigated the ability of a CpG-ODN formulated with Emulsigen to modulate functional responses of neutrophils in neonatal foals. Eighteen foals were randomly assigned to receive either a CpG-ODN with Emulsigen (N = 9) or saline intramuscularly at ages 1 and 7 days. At ages 1, 3, 9, 14, and 28, blood was collected and neutrophils were isolated from each foal. Neutrophils were assessed for basal and R...
Marenzoni ML, Sforna M, Stefanetti V, Casagrande Proietti P, Brignone L, Del Sero A, Falcioni F, Orvieto S, Tamantini C, Tiburzi A, Valentini S....In recent years, there has been increasing evidence of the potential pathogenic significance of equine gammaherpesviruses in the horse. In humans, cattle and mice, gammaherpesviruses have already been associated with uterine infection. The aim of the present study was to investigate the presence of gammaherpesviruses in uterine flushings of mares with reproductive problems and to evaluate if there was a possible statistical association with clinical and laboratory findings in these cases. A total of 80 uterine flushings were collected from 61 mares with different reproductive problems and thes...
Scopel e Silva D, de Castro CC, da Silva e Silva F, Sant'anna V, Vargas GD, de Lima M, Fischer G, Brandelli A, da Motta Ade S, Hübner Sde O.P34 is an antimicrobial peptide produced by a Bacillus sp. strain isolated from the intestinal contents of a fish in the Brazilian Amazon basin with reported antibacterial activity. The aim of this work was to evaluate the peptide P34 for its in vitro antiviral properties against canine adenovirus type 2 (CAV-2), canine coronavirus (CCoV), canine distemper virus (CDV), canine parvovirus type 2 (CPV-2), equine arteritis virus (EAV), equine influenza virus (EIV), feline calicivirus (FCV) and feline herpesvirus type 1 (FHV-1). The results showed that the peptide P34 exhibited antiviral activity a...
Conze TM, Bagó Z, Revilla-Fernández S, Schlegel J, Goehring LS, Matiasek K.A final diagnosis in a horse with clinical signs of encephalopathy can be challenging despite the use of extensive diagnostics. Clinical signs are often not pathognomonic and need to be interpreted in combination with (specific) laboratory results and epidemiological data of the geographical region of the origin of the case(s). Here we describe the diagnostic pathway of tick-borne encephalitis virus infection in two horses using established molecular diagnostic methods and a novel in situ hybridization technique to differentiate between regionally important/emerging diseases for central Europe...
Dutta SK, Myrup AC.A novel, simple method of infectious center assay was developed to detect and quantitate the intracellular existence of equine herpesvirus 1 and equine herpesvirus 2 in peripheral blood mononuclear cells infected in vivo and in vitro with the viruses by cocultivation of these cells with a permissive equine cell culture. The infectious center titers were correlated with the infectious virus titers. In vivo equine herpesvirus 1-infected mononuclear cells obtained from ponies experimentally infected with the virus and equine herpesvirus 2-infected mononuclear cells obtained from selected naturall...
Mealey RH, Stone DM, Hines MT, Alperin DC, Littke MH, Leib SR, Leach SE, Hines SA.Improving the ability of DNA-based vaccines to induce potent Type1/Th1 responses against intracellular pathogens in large outbred species is essential. Rhodoccocus equi and equine infectious anemia virus (EIAV) are two naturally occurring equine pathogens that also serve as important large animal models of neonatal immunity and lentiviral immune control. Neonates present a unique challenge for immunization due to their diminished immunologic capabilities and apparent Th2 bias. In an effort to augment R. equi- and EIAV-specific Th1 responses induced by DNA vaccination, we hypothesized that a du...
Phoutrides E, Jusino-Mendez T, Perez-Medina T, Seda-Lozada R, Garcia-Negron M, Davila-Toro F, Hunsperger E.After the isolation of West Nile virus (WNV) from humans, mosquitoes, and chickens in 2007, an analysis of animal surveillance involving multiple species (horses, monkeys, sheep, dogs, and birds) used to track WNV transmission from 2006 to 2008 was performed. During this period 13.4% of all the animal samples collected were seropositive by blocking ELISA for WNV. The most complete island-wide sampling was obtained from horses of which 22% were serologically positive and 96% were confirmed as WNV infections by plaque-reduction neutralization test. Our conclusion from this 3-year study is that a...
Benson CE, Sweeney CR.Streptococcus pneumoniae type 3 was isolated from seven tracheobronchial aspirates and one pleural tap of seven adult horses and one foal. There was no direct evidence in these horses that isolation of the pneumococcus was related to a specific disease syndrome. Presenting complaints included two horses with chronic cough, two horses with decreased exercise tolerance, one horse with exercise-induced pulmonary hemorrhage, and three horses with pneumonia. Antibiotic therapy resolved the primary clinical complaint. This is the first report of the isolation of S. pneumoniae type 3 from adult horse...
Redwan el-RM, Fahmy A, El Hanafy A, Abd El-Baky N, Sallam SM.In view of the disadvantages of human and equine rabies immunoglobulin still there is urgent needs for safe and cost-control anti-rabies immunoglobulins especially for person who have been severely exposed (categories III) to the virus. Our attempt to produce a less immunogenic and cheaper anti-rabies immunoglobulin affordable for those people living in developing countries, has been harnessed the ovine as a bioreactor instead the horse. The animals have been intramuscular immunized, and the plasma processed with 5% caprylic acid to yield IgG with purity of 95%. Moreover, antibody apparently i...
Back H, Berndtsson LT, Gröndahl G, Ståhl K, Pringle J, Zohari S.Equine Influenza Virus (EIV) is a major cause of respiratory disease in horses and the virus constantly undergoes antigenic drift. Here we characterize and describe the HA1 and the NA genes of H3N8 within samples obtained from outbreaks in Sweden during November-December 2011. Both clade 1 and clade 2 viruses of the Florida sublineage were identified. The index case of clade 2 was transported to Sweden from Spain through the Netherlands, whereas the clade 1 had its origin from a Swedish stud farm. The clade 1 virus was efficiently spread between training yards by unvaccinated young horses, but...
Sijmons S, Vissani A, Tordoya MS, Muylkens B, Thiry E, Maes P, Matthijnssens J, Barrandeguy M, Van Ranst M.Equid herpesvirus 3 (EHV-3) is a member of the subfamily Alphaherpesvirinae that causes equine coital exanthema. Here, we report the first complete genome sequence of EHV-3. The 151,601-nt genome encodes 76 distinct genes like other equine alphaherpesviruses, but genetically, EHV-3 is significantly more divergent.
Vesonder R, Haliburton J, Stubblefield R, Gilmore W, Peterson S.Corn from an Arkansas farm, where three horses died and others became sick, was investigated for causative principles. Necropsy of the three horses revealed what appeared to be severe hepatic necrosis. Histopathological examination indicated a pattern of hepatic lesions that was suggestive of aflatoxin contamination of the feed. Mycological examination of the corn by dilution plating revealed 95% of the colonies as Aspergillus flavus. Chemical analysis of the corn for mycotoxins was positive for aflatoxin B1, B2, and M1 at concentrations of 114, 10, and 6 micrograms/Kg, respectively. Cyclopiaz...
Parma AE, Sanz ME, Lucchesi PM, Mazzonelli J, Petruccelli MA.A protein epitope which is involved in an antigenic relationship between equine ocular tissues and Leptospira interrogans was detected in homogenates of the bacterium. The antigenic determinant was harboured on a peptide structure which was shown to be sensitive to the action of denaturing and reducing agents by means of Western blotting. The outer surface of the leptospires appeared to be free of this epitope as was proved by dot-blot and electron microscopic studies.
Klouth E, Zablotski Y, Petersen JL, de Bruijn M, Gröndahl G, Müller S, Goehring LS.Equid Herpesvirus Myeloencephalopathy (EHM) is a multifactorial disease following an EHV-1 infection in Equidae. We investigated a total of 589 horses on 13 premises in Europe in search of risk factors for the development of EHM. We found that fever ( < 0.001), increasing age ( = 0.032), and female sex ( = 0.042) were risk factors for EHM in a logistic mixed model. Some breeds had a decreased risk to develop EHM compared to others (Shetland and Welsh ponies; = 0.017; = 0.031), and fewer EHV-1-vaccinated horses were affected by EHM compared to unvaccinated horses ( = 0.02). Data evaluation...
Barrera R, Torres N, Freier JE, Navarro JC, García CZ, Salas R, Vasquez C, Weaver SC.The distribution of the sylvatic subtype ID Venezuelan equine encephalitis (VEE) viruses in the lowland tropical forests of western Venezuela was investigated using remote sensing and geographic information system technologies. Landsat 5 Thematic Mapper satellite imagery was used to study the reflectance patterns of VEE endemic foci and to identify other locations with similar reflectance patterns. Enzootic VEE virus variants isolated during this study are the closest genetic relatives of the epizootic viruses that emerged in western Venezuela during 1992-1993. VEE virus surveillance was condu...
Balantidium coli is a ciliated protozoan that inhabits the large intestine of swine, man, rodents, and nonhuman primates. Frequently this organism is associated with enteric diseases in man and nonhuman primates, with rare manifestations of disease in swine and other mammalian species. This report describes a case of B. coli-induced enteric disease in a 15-yr-old, mare, Finnish Horse after an acute onset of colic. Severe hemorrhagic and eosinophilic colitis with intense infiltration of intralesional B. coli-like ciliated protozoan were found histologically.
Jones RL, Adney WS, Alexander AF, Shideler RK, Traub-Dargatz JL.Severe hemorrhagic necrotizing enterocolitis was determined to be the cause of death for 4 foals. Toxigenic Clostridium difficile was isolated form the intestine of each foal, and large, gram-positive, rod-shaped bacteria lined the surface of necrotic villi. This finding of toxigenic C difficile associated with enteritis in foals adds another possible cause to the list of infectious agents that should be considered when evaluating foals with enteritis. Definitive diagnosis requires a thorough diagnostic evaluation, including procedures that will identify the organism and demonstrate its toxige...
Yuan ZQ, Bennett L, Campo MS, Nasir L.BPV-1 and less commonly BPV-2 are associated with the pathogenesis of equine skin tumours termed sarcoids. We recently documented the transcriptional changes that are induced by BPV-1 in equine fibroblasts using microarray analyses. TLR4 expression was found to be significantly down-regulated by BPV-1. In the present study, we show that TLR4 expression is significantly decreased following the exogenous expression of BPV-1 E2 and E7 in primary equine fibroblasts. The results were confirmed by the demonstration of increased TLR4 expression following siRNA suppression of BPV-1 E2 and E7 viral gen...
El-Hage CM, Bamford NJ, Gilkerson JR, Lynch SE.Ross River virus (RRV) is a mosquito-borne arbovirus of the genus Alphavirus that causes disease in humans and horses in Australia. A temporal association of RRV infection in horses with clinical signs including pyrexia, malaise, and polyarthralgia has been reported, along with reduced athletic performance, often for extended periods. Despite these reports, disease due to RRV remains somewhat controversial as experimental infection of horses has resulted in obvious viraemia yet minimal signs of clinical disease. The relatively high viraemia demonstrated by horses infected with RRV has led to s...
Dubey JP.Thirteen 6-month- to 13-year-old equids were each inoculated orally with 10,000 infective Toxoplasma gondii oocysts. The equids remained clinically normal. Equids were euthanatized on postinoculation days 33, 45, 90, 104, 120, 140, 162, 183, 197, 204, 211, 294, and 476. Their tissues were bioassayed for viable oocysts by feeding muscles to Toxoplasma-free cats and by inoculation of pepsin digests of 13 organs into mice. Using mouse inoculation, T gondii was recovered from tissues of the 9 equids euthanatized on each of postinoculation days 33, 45, 120, 140, 183, 197, 211, 294, and 476. Toxopla...
Scala A, Tamponi C, Sanna G, Predieri G, Meloni L, Knoll S, Sedda G, Dessì G, Cappai MG, Varcasia A.Equine ascariosis, caused by Parascaris spp., is a worldwide endoparasitic disease affecting young horses in particular. Despite the great number of horses reared in Italy, large-scale epidemiological surveys dealing with ascariosis prevalence in the country are not reported in the current literature. For this reason, the present survey aims to describe, for the first time, the spread and infestation of Parascaris spp. in a large population of Italian horses (6896 animals) using faecal egg counts, and further to identify risk factors associated with ascarid egg shedding. Methods: Individual re...
Preziuso S, Pinho MD, Attili AR, Melo-Cristino J, Acke E, Midwinter AC, Cuteri V, Ramirez M.Streptococcus dysgalactiae subsp. equisimilis (SDSE) can be severely pathogenic in humans and is increasingly isolated from horses with respiratory, reproductive or other diseases, although it is often considered a commensal bacterium. Here a PCR protocol is described for identifying SDSE recovered from humans. A multiplex PCR targeting the 16S rRNA and the streptokinase precursor gene has been optimized for differentiating between SDSE strains isolated from humans and those isolated from horses. Previously, the sequence of the streptokinase precursor gene of SDSE recovered from horses has bee...
Browning GF, Studdert MJ.The BamHI, EcoRI, and HindIII physical maps of the genomes of 14 isolates of equine herpesvirus 2 (EHV 2) were determined by Southern blot analysis using DNA fragments of a previously mapped EHV 2 strain 86/67. No two isolates had identical maps for all 3 enzymes, the number of differing cleavage sites between pairs of isolates varying from 3 to 21. Overall 75 cleavage sites were mapped, of which 40 were variable. Cleavage sites occurred throughout the genome, including within the terminal repeat regions. Additionally, fragment length polymorphisms, independent of cleavage site loss or gain, w...
Gutiérrez S, Thébaud G, Smith DR, Kenney JL, Weaver SC.The within-host diversity of virus populations can be drastically limited during between-host transmission, with primary infection of hosts representing a major constraint to diversity maintenance. However, there is an extreme paucity of quantitative data on the demographic changes experienced by virus populations during primary infection. Here, the multiplicity of cellular infection (MOI) and population bottlenecks were quantified during primary mosquito infection by Venezuelan equine encephalitis virus, an arbovirus causing neurological disease in humans and equids.
Epp TY, Waldner C, Berke O.The objective of this study was to develop a model using equine data from geographically limited surveillance locations to predict risk categories for West Nile virus (WNV) infection in horses in all geographic locations across the province of Saskatchewan. The province was divided geographically into low-, medium-, or high-risk categories for WNV, based on available serology information from 923 horses obtained through 4 studies of WNV infection in horse populations in Saskatchewan. Discriminant analysis was used to build models using the observed risk of WNV in horses and geographic division...
Wilkins PA, Glaser AL, McDonnell SM.Horses naturally exposed to West Nile Virus (WNV) or vaccinated against WNV develop humoral immunity thought to be protective against development of clinical disease in exposed or infected animals. No reports evaluate the efficacy of passive transfer of naturally acquired specific WNV humoral immunity from dam to foal. The purpose of this study was to investigate passive transfer of naturally acquired immunity to WNV to foals born in a herd of semi-feral ponies, not vaccinated against WNV, in an endemic area, with many dams having seroconverted because of natural exposure. Microwell serum neut...
Scacchia M, Cammà C, Di Francesco G, Di Provvido A, Giunta R, Luciani M, Marino AM, Pascucci I, Caporale V.In May 2011, dourine was reported in Italy following the declaration of a positive result observed in a stallion undergoing routine testing for stud purposes. Clinical signs, anatomo-histopathological findings and laboratory results that resulted in the confirmation of diagnosis of dourine in a clinically affected mare, which was the likely source of infection in the stallion, are described.
Barr B, Nieman NM.Sepsis is a significant cause of morbidity and mortality in neonatal foals, especially during the first 7 days of life. Diagnosing sepsis in neonatal foals can be challenging because initial clinical signs are often ambiguous and non-specific. Objective: To determine if the major acute phase protein serum amyloid A (SAA) as measured by a point-of-care SAA testing device can be used as an evidence-based biomarker of sepsis. Methods: Retrospective cohort. Methods: Clinical diagnosis of sepsis based on positive bacterial blood culture or a positive sepsis score was obtained and compared to SAA v...
Leigh JA.A protein capable of activating bovine, equine and ovine plasminogen, but not that from human or porcine plasma, was purified from culture filtrates of Streptococcus uberis (strain 0140J). Purification was achieved by ammonium sulphate precipitation followed by molecular exclusion chromatography. The elution position of the native molecule was equivalent to a molecular mass of approximately 57 kDa. However, the molecular mass, as determined by SDS-PAGE, was 29 kDa, suggesting the existence of a dimeric structure. Purified immunoglobulin from three out of five monoclonal antibodies raised to th...
