Epidemiology in horses involves the study of the distribution and determinants of health-related states and events in equine populations. It encompasses the investigation of patterns, causes, and effects of diseases and health conditions within horse populations. This field of study aims to identify risk factors for disease and targets for preventive healthcare. Key components of equine epidemiology include disease surveillance, outbreak investigation, and the study of disease dynamics within herds or regions. Research in this area often focuses on infectious diseases, zoonotic diseases, and the impact of environmental factors on equine health. This page compiles peer-reviewed research studies and scholarly articles that explore various aspects of epidemiology in horses, including disease prevalence, transmission pathways, and strategies for disease prevention and control.
Schuler LA, Khaitsa ML, Dyer NW, Stoltenow CL.To characterize an outbreak of West Nile virus (WNV) infection in horses in North Dakota in 2002, evaluate vaccine effectiveness, and determine horse characteristics and clinical signs associated with infection. Methods: Retrospective study. Methods: 569 horses. Methods: Data were obtained from veterinary laboratory records, and a questionnaire was mailed to veterinarians of affected horses. Results: Affected horses were defined as horses with typical clinical signs and seroconversion or positive results of virus isolation; affected horses were detected in 52 of the 53 counties and concentrate...
Gross DK, Morley PS, Hinchcliff KW, Reichle JK, Slemons RD.The purpose of this investigation was to determine if naturally occurring acute infectious upper respiratory disease (IRD) caused by equine influenza virus is associated with ultrasonographically detectable pleural and pulmonary abnormalities in horses. Standardbred racehorses were evaluated for signs of IRD, defined as acute coughing or mucopurulent nasal discharge. For every horse with IRD (n = 16), 1 or 2 horses with no signs of IRD and the same owner or trainer (n = 30) were included. Thoracic ultrasonography was performed within 5-10 days of the onset of clinical disease in horses with IR...
Balasuriya UB, MacLachlan NJ.The members of the family Arteriviridae, genus Arterivirus, include equine arteritis virus (EAV), porcine reproductive and respiratory syndrome virus (PRRSV), lactate dehydrogenase-elevating virus (LDV) of mice, and simian hemorrhagic fever virus (SHFV). PRRSV is the newest member of the family (first isolated in North America and Europe in the early 1990s), whereas the other three viruses were recognized earlier (EAV in 1953, LDV in 1960, and SHFV in 1964). Although arterivirus infections are strictly species-specific, the causative agents share many biological and molecular properties, inclu...
Koekemoer JJ, Dijk AA.Since protection against African horsesickness (AHS) is serotype-specific, rapid serotyping of AHSV is crucial to identify the correct vaccine serotype for efficient control of the spread of AHS outbreaks, especially when they occur in non-endemic regions. This paper describes the first one-day serotyping procedure that requires only a single RT-PCR and hybridization and which can identify multiple serotypes in mixed infections in one assay. The same region of genome segment 2 of all nine AHSV serotypes is amplified in a single RT-PCR. A universal primer set, designed to amplify the 5'-termina...
Herrera HM, Dávila AM, Norek A, Abreu UG, Souza SS, D'Andrea PS, Jansen AM.In order to better understand the enzootiology of trypanosomiasis caused by Trypanosoma evansi in the Brazilian Pantanal we examined domestic and wild mammals by microhematocrit centrifuge technique (MHCT), immunofluorescence antibody test (IFAT) and polymerase chain reaction (PCR). T. evansi infection was detected in all species sampled with exception of the sheep and the feral pig. High parasitemias were observed in capybaras (5/24), coatis (18/115), horses (31/321) and dogs (3/112). Among these species, only the capybaras did not develop anemia. Low parasitemias, only detected by PCR, were ...
Kaplan RM, Klei TR, Lyons ET, Lester G, Courtney CH, French DD, Tolliver SC, Vidyashankar AN, Zhao Y.To determine prevalence of anthelmintic resistance in cyathostome nematodes of horses in the southern United States. Methods: Cross-sectional study. Methods: 786 horses on 44 farms and stables in Georgia, South Carolina, Florida, Kentucky, and Louisiana. Methods: Fecal egg count (FEC) reduction tests were performed on 44 large farms and stables. Horses on each farm were treated with an oral paste formulation of fenbendazole, oxibendazole, pyrantel pamoate, or ivermectin at recommended label dosages. A mixed linear model was fitted to the percentage reduction in FEC, accounting for differences ...
Linde HJ, Kobuch R, Jayasinghe S, Reischl U, Lehn N, Kaulfuss S, Beutin L.We report the first case of a postoperative wound infection caused by Vibrio metschnikovii on the lower right leg of a patient after saphenectomy. Compared to the healing of an uninfected site, that of the right leg was delayed, and a cure was achieved by intensified wound care. Several swabs taken from the infected site grew a gram-negative rod in pure culture that was identified as V. metschnikovii by the VITEK 2 system. The source of the infection was not detected; however, the absence of putative risk factors (exposure to water or shellfish or an episode of diarrhea), the profession of the...
Parkin TD, Clegg PD, French NP, Proudman CJ, Riggs CM, Singer ER, Webbon PM, Morgan KL.Considerable variation in the rates of equine fatality at different racecourses draws attention to probable risk factors at the level of course or race that might be partly responsible. Distal limb fractures are the most common cause of equine fatality on UK racecourses and identification of risk factors for such injuries and subsequent implementation of intervention strategies could significantly reduce the total number of racecourse fatalities. Objective: To identify race- and course-level risk factors for fatal distal limb fracture in Thoroughbreds on UK racecourses. Methods: A case-control...
Parkin TD, Clegg PD, French NP, Proudman CJ, Riggs CM, Singer ER, Webbon PM, Morgan KL.Fractures below the level of the radius or tibia (distal limb fractures) are the most common cause of equine fatality on UK racecourses; however, little is known about their epidemiology or aetiology. Identification of risk factors could enable intervention strategies to be designed to reduce the number of fatalities. Objective: To identify horse-level risk factors for fatal distal limb fracture in Thoroughbreds on UK racecourses. Methods: A case-control study design was used. Fractures in case horses were confirmed by post mortem examination and 3 matched uninjured controls were selected from...
Bernard WV, LeBlanc MM, Webb BA, Stromberg AJ.To determine whether gavage of pregnant mares (housed without access to pasture) with starved eastern tent caterpillars (ETCs) or their excreta is associated with early fetal loss (EFL), panophthalmitis, or pericarditis. Methods: Randomized clinical trial. Methods: 15 mares. Methods: 15 mares with fetuses from 40 to 80 days of gestation (dGa) were randomly assigned to 1 of 3 groups and received 2.5 g of ETC excreta, 50 g of starved ETCs, or 500 mL of water, respectively, once daily for 10 days. Mares were housed in box stalls, walked twice daily, and not allowed access to pasture for 12 days b...
Berthoud H, Frey J, Sternberg S, Straub R, Kuhnert P.Actinobacillus equuli is found in the normal oral flora of horses, but has been associated with several diseases, and particularly with the usually fatal septicaemia in neonatal foals which is thought to be associated with a failure of the passive transfer of immunoglobulins via the colostrum. The Aqx protein of A equuli, belonging to the RTX family of pore-forming toxins, is also cytotoxic to horse lymphocytes. The presence of antibodies to Aqx was investigated in sera from individual horses from different regions; the sera from adult horses and foals 24 hours after birth reacted with Aqx, an...
Döpfer D, Kerssens CM, Meijer YG, Boersema JH, Eysker M.Faeces of 484 horses were sampled twice with an interval of 6 weeks while anthelmintic therapy was halted. Faecal eggs counts revealed that 267 (55.2%) horses had consistently low numbers of eggs per gram faeces (EPG) (EPG 100). Horses with consistently high EPGs were more often mares with access to pasture, aged less than 6 or more than 23 years, that were dewormed at intervals longer than 6 months, and were treated for the last time more than 3 months before the start of the study. Horses with consistently low EPGs were more often male horses with no or limited access to pasture, that were ...
Singh BK, Ahuja S, Gulati BR.A single-dilution, sensitive and specific monoclonal antibody-based blocking enzyme-linked immunosorbent assay (B-ELISA) was developed as an alternative to the cumbersome virus neutralization test (VNT) for detection of equine herpesvirus-1 (EHV-1) antibodies. Neutralizing monoclonal antibodies (1H6 and 9C6) raised against EHV-1 (Hisar-90-7 strain) and sera from 70 horses (30 known negative and 40 known positive for EHV-1 antibodies by VNT) were used for standardization of the B-ELISA. Using a single serum dilution of 1:250 in B-ELISA, 100% specificity was obtained with both monoclonal antibod...
Ocholi RA, Kwaga JK, Ajogi I, Bale JO.Isolation of brucellae from aborted fetuses, hygroma fluids, milk and vaginal swabs obtained from aborting cattle, sheep, goats, pigs, and horses in Nigeria was carried out. A total of 25 isolates, obtained mainly from cattle, sheep and horses, were biotyped. All strains belonged to one species, Brucella abortus biovar 1. The epidemiological significance of this finding is discussed. Some preliminary observations on the zoonotic and public health implications of Brucella infection in Nigerian livestock are presented. A control programme involving improved management, animal movement restrictio...
Cupp EW, Zhang D, Yue X, Cupp MS, Guyer C, Sprenger TR, Unnasch TR.Uranotaenia sapphirina, Culex erraticus, and Cx. peccator were collected in an enzootic eastern equine encephalomyelitis (EEE) virus focus in central Alabama (Tuskegee National Forest) from 2001 to 2003 and analyzed for virus as well as host selection. EEE virus was detected in each species every year except 2003, when pools of Cx. peccator were negative. Most (97%) of the 130 Cx. peccator blood meals identified were from ectothermic hosts; 3% were from birds. Among blood meals from reptiles (approximately 75% of the total), 81% were from Agkistrodon piscivorus (cottonmouth); all amphibian blo...
Shirato K, Kimura T, Mizutani T, Kariwa H, Takashima I.West Nile (WN) virus is a mosquito-borne flavivirus that can cause lethal encephalitis in humans and horses. The WN virus endemic in New York City (NY) in 1999 caused large-scale mortality of wild birds that was not evident in endemic areas in other parts of the world, and the pathogenesis of the WN virus strain isolated in NY (NY strain) appears to differ from that of previously isolated strains. However, the pathogenesis of NY strain infection remains unclear. This study examined CC (RANTES/CCL5, MIP-1 alpha/CCL3, MIP-1 beta/CCL4) and CXC (IP-10/CXCL10, B lymphocyte chemoattractant (BLC/CXCL...
Kaplan RM.Reports of drug resistance have been made in every livestock host and to every anthelmintic class. In some regions of world, the extremely high prevalence of multi-drug resistance (MDR) in nematodes of sheep and goats threatens the viability of small-ruminant industries. Resistance in nematodes of horses and cattle has not yet reached the levels seen in small ruminants, but evidence suggests that the problems of resistance, including MDR worms, are also increasing in these hosts. There is an urgent need to develop both novel non-chemical approaches for parasite control and molecular assays cap...
Daly JM, Yates PJ, Newton JR, Park A, Henley W, Wood JL, Davis-Poynter N, Mumford JA.Two lineages of antigenically distinct equine influenza A H3N8 subtype viruses, American and European, co-circulate. Experiments were conducted in ponies to investigate the protection induced by vaccines containing virus from one lineage against challenge infection with homologous or heterologous virus. Regression analysis showed that vaccinated ponies with average pre-challenge single radial haemolysis (SRH) antibody levels (i.e. 45-190mm2) had a higher probability of becoming infected if they were vaccinated with virus heterologous to the challenge strain than if they were vaccinated with ho...
Newton JR, Geraghty RJ, Castillo-Olivares J, Cardwell JM, Mumford JA.Several laboratories worldwide have recently experienced problems related to serum cytotoxicity with the equine arteritis virus (EAV) neutralisation test (VN) when using Office International des Epizooties (OIE) reference laboratory prescribed rabbit kidney (RK-13) indicator cells. Cytotoxicity can be mistaken for viral cytopathic effect and has led to increasing difficulties in test interpretation, consequently causing disruption to both equine breeding and disease surveillance. Results from experimental and field-derived data suggest that this serum cytotoxicity is associated with use of a t...
Hancock K, Zajac AM, Elvinger F, Lindsay DS.Equine protozoal myeloencephalitis is the most important protozoan disease of horses in North America and is usually caused by Sarcocystis neurona. Natural and experimentally induced cases of encephalitis caused by S. neurona have been reported in raccoons (Procyon lotor) and raccoons are an intermediate host for this parasite. A 3-yr-long serological survey was conducted to determine the prevalence of agglutinating antibodies to S. neurona in raccoons collected from Fairfax County, Virginia, a suburban-urban area outside Washington, D.C. Samples from 469 raccoons were examined, and agglutinat...
Landman MA, de Blaauw JA, van Weeren PR, Hofland LJ.A population of 805 horses (70 per cent dressage, 20 per cent show jumpers and 10 per cent trotters) with orthopaedic problems was examined for signs of lameness and back problems, irrespective of their original complaints. In the horses with a back problem the prevalence of lameness was 74 per cent, and back problems were diagnosed in 32 per cent of the lame horses. These percentages were significantly higher than those recorded in a control population of 399 horses, of which 20 per cent were lame and 12 per cent had back problems. In the group of horses with orthopaedic problems there was a ...
Elsheikha HM, Mansfield LS.Sarcocystis neurona has become recognized as the major causative agent of equine protozoal myeloencephalitis (EPM) in the Americas. At least 3 pathogenic species of Sarcocystis, including S. neurona, can be isolated from opossums. Methods are needed to ascertain whether these isolates are viable and capable of causing infections. In this study, the nuclear stain propidium iodide (PI) was used to differentiate between live (viable) and heat-killed (nonviable) S. neurona sporocysts. PI was excluded by live sporocysts but penetrated compromised sporocyst membrane and stained sporozoite nuclei of ...
Drogemuller M, Schnieder T, von Samson-Himmelstjerna G.The molecular mechanism of benzimidazole (BZ) resistance in cyathostomins of horses is still unclear. Previous studies revealed that the TTC or TAC polymorphism in codon 200 of the beta-tubulin isotype 1 gene is not as strictly correlated with BZ resistance as in trichostrongyles in sheep. To identify further sites of polymorphism within the beta-tubulin gene related to BZ resistance, complete complementary DNAs (cDNAs) encoding beta-tubulin of adult worms of Cylicocyclus nassatus, Cyathostomum pateratum, Cyathostomum coronatum, Cyathostomum catinatum, Cylicostephanus longibursatus, and Cylico...
Duarte PC, Conrad PA, Wilson WD, Ferraro GL, Packham AE, Bowers-Lepore J, Carpenter TE, Gardner IA.To estimate risk of exposure and age at first exposure to Sarcocystis neurona and Neospora hughesi and time to maternal antibody decay in foals. Methods: 484 Thoroughbred and Warmblood foals from 4 farms in California. Methods: Serum was collected before and after colostrum ingestion and at 3-month intervals thereafter. Samples were tested by use of the indirect fluorescent antibody test; cutoff titers were > or = 40 and > or = 160 for S neurona and N hughesi, respectively. Results: Risk of exposure to S neurona and N hughesi during the study were 8.2% and 3.1%, respectively. Annual rate...
Salazar P, Traub-Dargatz JL, Morley PS, Wilmot DD, Steffen DJ, Cunningham WE, Salman MD.To determine outcome of equids in the western United States with clinical signs of West Nile virus (WNV) infection and identify factors associated with risk of death in infected equids. Methods: Cross-sectional study. Methods: 484 equids in Nebraska and Colorado. Methods: Owners of 484 equids with laboratory-confirmed West Nile virus infection in Nebraska and Colorado were contacted by telephone, and a questionnaire was used to obtain information on signalment, management, clinical signs, date of disease onset, duration of disease, WNV vaccination status, and health status at the time of the i...
Blitvich BJ, Fernández-Salas I, Contreras-Cordero JF, Loroño-Pino MA, Marlenee NL, Díaz FJ, González-Rojas JI, Obregón-Martínez N....West Nile virus RNA was detected in brain tissue from a horse that died in June 2003 in Nuevo Leon State, Mexico. Nucleotide sequencing and phylogenetic analysis of the premembrane and envelope genes showed that the virus was most closely related to West Nile virus isolates collected in Texas in 2002.
Murrell KD, Djordjevic M, Cuperlovic K, Sofronic Lj, Savic M, Djordjevic M, Damjanovic S.A discovery in 2002 of a Trichinella spiralis-infected horse in Serbia offered an opportunity to conduct needed epidemiological studies on how horses, considered herbivores, acquire a meat-borne parasite. This enigma has persisted since the first human outbreaks from infected horse meat occurred in then 1970s. The trace back of the infected horse to a farm owner was carried out. Interviews and investigations on the farm led to the conclusion that the owner had fed the horse food waste in order to condition the horse prior to sale. Further investigations were then carried out to determine the f...
Szeredi L, Hornyák A, Pálfi V, Molnár T, Glávits R, Dénes B.The occurrence of equine arteritis virus (EAV) induced equine abortions was studied with different laboratory methods during a 3-year period. Tissue samples from 96 aborted equine foetuses or newborn foals were collected from 57 farms located in different parts of Hungary. Virus isolation, polymerase chain reaction (PCR), immunohistochemistry and serology were used for the detection of EAV infection. The overall seroprevalence of EAV infection in mares was 65%. EAV induced abortion was diagnosed in eight (8.3%) cases from six (10.5%) herds. Abortion was sporadic in all herds except for one, wh...
Butler AJ, Greenbank H, Parrish R, Nielsen MK, Stoughton WB.Cyathostomins are the most common parasites of adult horses worldwide. Currently, the three classes of anthelmintics used to treat cyathostomin infections includes benzimidazoles, pyrimidines and macrocyclic lactones. However, due to widespread overuse, cyathostomins have developed varying degrees of resistance to all classes of anthelmintics. Fecal egg count reduction tests (FECRT) are currently used to determine the presence of anthelmintic resistance (AR), while egg reappearance periods (ERP) are used to investigate early macrocyclic lactone resistance. The objective of this study was to in...
Cohen D, Bosler EM, Bernard W, Meirs D, Eisner R, Schulze TL.A serologic survey of horses in the New Jersey-Pennsylvania area demonstrated that about 10% (6.2-14.2%) have significant levels of serum antibody to Borrelia burgdorferi. However, in a highly endemic area of central New Jersey, up to 60% of the mares and yearlings samples on one farm were seropositive. In 1983, sera from this same farm exhibited only 12% positives in mares and 35% positives in yearlings. Longitudinal studies of paired sera obtained from individual yearlings over a 6-month period in 1985 showed that 34% of them declined during the period. A new clinical syndrome associated wit...
Santos EM, Cardoso R, Souza GR, Goulart LR, Heinemann MB, Leite RC, Reis JK.Equine infectious anemia caused by equine infectious anemia virus is an important disease due to its high severity and incidence in animals. We used a phage display library to isolate peptides that can be considered potential markers for equine infectious anemia diagnosis. We selected peptides using IgG purified from a pool comprised of 20 sera from animals naturally infected with equine infectious anemia virus. The diagnostic potential of these peptides was investigated by ELISA, Western blot and dot blot with purified IgG and serum samples. Based on the results, we chose a peptide mimetic fo...
Söderroos D, Ignell R, Haubro Andersen P, Bergvall K, Riihimäki M.Insect bite hypersensitivity (IBH) associated with biting midges is a common allergic skin disease in horses, reducing the welfare of affected horses. This study investigated the effect of IBH on animal welfare and behaviour and assessed a new prophylactic insect repellent. In total, 30 horses were recruited for a prospective cross-over and case-control study. Clinical signs of IBH, inflammatory markers in skin biopsies and behavioural data (direct observations, motion index) were scored longitudinally during two consecutive summers. No differences were observed in the total number of itching...
Norris JW, Pratt SM, Hunter JF, Gardner IA, Tablin F.To measure the frequency and magnitude of reduced fibrinogen binding in a population of horses from a Thoroughbred breeding farm. Methods: 444 Thoroughbred horses, 1 to 27 years old, including 316 females, 72 geldings, and 56 sexually intact males. Methods: Blood was collected from horses into tubes containingacid citrate dextrose adenine, and washed platelets were examined by use of flow cytometry for their ability to bind fibrinogen. Results: Data regarding fibrinogen binding to activated platelets were normally distributed, with nearly identical amounts of variation regardless of sex. In 3 ...
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...
Hopper BJ, Steel C, Richardson JL, Alexander GR, Robertson ID.Sclerosis of the third carpal bone is a common radiographic finding in both lame and sound racehorses, but there are no guidelines correlating degree of sclerosis and incidence of lameness. Objective: To develop a protocol for describing subchondral bone sclerosis in C3 on dorsoproximal-dorsodistal oblique (DPr-DDiO) radiographs of the carpus and to correlate these changes with exercise history and carpal lameness. Methods: One hundred and six Standardbreds entering their first year of training (exercise group) and 7 age-matched Standardbreds at pasture (controls) were examined at approximatel...
Studdert MJ, Fitzpatrick DR, Horner GW, Westbury HA, Gleeson LJ.Representative strains of EHV isolated from an aborted foetus and from a horse with rhinopneumonitis in New Zealand had restriction endonuclease DNA fingerprints typical of those usually associated with these syndromes elsewhere and now designated EHV1 and 4 respectively. EHV1 was isolated from the brain and spinal cord of a 4-year-old gelding that died of myeloencephalitis. A mare on the same farm, at about the same time as the gelding developed myeloencephalitis, aborted and EHV1 was isolated from the tissues of the aborted foetus. Restriction endonuclease DNA fingerprints of the viruses iso...
Yin X, Lu G, Guo W, Qi T, Ma J, Zhu C, Zhao S, Pan J, Xiang W.An outbreak of equine influenza was observed in the Asian wild horse population in Xinjiang Province, China, in 2007. Nasal swabs were collected from wild horses and inoculated into 9-10-day SPF embryonated eggs. The complete genome of the isolate was sequenced. A comparison of the amino acid sequence revealed that the isolate was an equine influenza virus strain, which we named A/equine/Xinjiang/4/2007. Each gene of the virus was found to have greater than 99 % homology to equine influenza virus strains of the Florida-2 sublineage, which were circulating simultaneously in China, and a lesser ...
El-Hage CM, Bannai H, Wiethoelter AK, Firestone SM, Heislers CM, Allen JL, Waller AS, Gilkerson JR.To determine the nature of serological responses in Australian horses using a commercial duplex indirect ELISA (iELISA) following vaccination against strangles. Methods: A group (n = 19) of client-owned horses from five properties were recruited to receive a primary course of a Streptococcus equi subsp. equi (S. equi) extract vaccine. Serological responses were determined by duplex iELISA incorporating S. equi-specific fragments of two cell wall proteins, SEQ2190 and SeM (antigens (Ag) A and C, respectively). Methods: The horses were administered a primary strangles vaccination course. Blood w...
Noordwijk KJ, Chen L, Ruspi BD, Schurer S, Papa B, Fasanello DC, McDonough SP, Palmer SE, Porter IR, Basran PS, Donnelly E, Reesink HL.Proximal sesamoid bone (PSB) fracture is the leading cause of fatal musculoskeletal injury in Thoroughbred racehorses in Hong Kong and the US. Efforts are underway to investigate diagnostic modalities that could help identify racehorses at increased risk of fracture; however, features associated with PSB fracture risk are still poorly understood. The objectives of this study were to (1) investigate third metacarpal (MC3) and PSB density and mineral content using dual-energy X-ray absorptiometry (DXA), computed tomography (CT), Raman spectroscopy, and ash fraction measurements, and (2) investig...
Shen DT, Crawford TB, Gorham JR, McGuire TC.Twelve chemicals and commercial disinfectants were tested for inactivation of equine infectious anemia virus. In the presence of 10% bovine serum, all chemicals inactivated 4 log10 (based on 0.1 ml) of the virus within 5 minutes at 23 C. A reduction of at least 4 log10 was observed when the virus was exposed for 1 minute to substituted phenolic disinfectants (3 commercial preparations and sodium orthophenylphenate), halogen derivatives (iodophor and sodium hypochlorite), chlorhexidine, and 70% ethanol. Sodium hydroxide (5%), 2% formalin, and 2% glutaraldehyde were slower to inactivate the viru...
Hassanien RT, Hussein HA, Abdelmegeed HK, Abdelwahed DA, Khattab OM, Ali MH, Habashi AR, Ibraheem EM, Shahein MA, Abohatab EM.Due to climatic changes, arthropod-borne viruses have become a global health concern. In Egypt, West Nile virus (WNV) was initially detected in humans in 1950 and then in 1951, 1954, 1968, and 1989. Although WNV infection has been recorded in numerous Middle Eastern countries, its prevalence among the equine population in Egypt is unknown. This study aimed to investigate the current situation of vector-borne WNV in Egypt, estimate its seroprevalence, and assess the associated risk factors. Unassigned: We screened 1100 sera samples and nasal swabs from the same equids, 156 mosquito pools, and 3...
Randleff-Rasmussen PK, Leblond A, Cappelle J, Bontemps J, Belluco S, Popoff MR, Marcillaud-Pitel C, Tapprest J, Tritz P, Desjardins I.Equine grass sickness (EGS) (equine dysautonomia) is a neurodegenerative condition of grazing equines. Pre-mortem diagnosis of EGS is a challenge for practitioners as definitive diagnosis requires ileal/myenteric lymph node biopsies. This study aimed to develop a clinical score that could be used by practitioners to improve the detection of acute or subacute EGS cases in the field. Suspected EGS cases were declared by veterinary practitioners. A case was classified as confirmed positive if ileal or rectal biopsy samples showed neuronal degeneration typical of EGS. A semi-quantitative scoring s...
Seahorn TL, Groves MG, Harrington KS, Beadle RE.To evaluate chronic obstructive pulmonary disease of horses in Louisiana by assessing the signalment, history, environmental factors, clinical signs, and treatment of such horses. Methods: Epidemiologic mail survey. Methods: 83 of 240 veterinarians contacted by mail agreed to take part in the survey. Veterinarians contacted were listed as mixed-animal or equine practitioners in the 1991/1992 directory of the Louisiana Veterinary Medical Association or had submitted a specimen from a horse to the Louisiana Veterinary Medical Diagnostic Laboratory within the past 2 years. Methods: The survey con...
McFadden AM, Pearce PV, Orr D, Nicoll K, Rawdon TG, Pharo H, Stone M.To summarise investigation and laboratory data collected between 2001 and 2011 to provide evidence that equine arteritis virus is not present in the horse population of New Zealand. Methods: Analysis was carried out on results from laboratory tests carried out at the Ministry for Primary Industries Animal Health Laboratory (AHL) for equine arteritis virus from horses tested prior to being imported or exported, testing of stallions as part of the New Zealand equine viral arteritis (EVA) control scheme and testing as part of transboundary animal disease (TAD) investigations for exclusion of EVA....
Sturgill TL, Giguère S, Franklin RP, Cohen ND, Hagen J, Kalyuzhny AE.The objectives of the present study were to determine if administration of inactivated parapoxvirus ovis (IPPVO) can decrease the cumulative incidence of pneumonia and increase the number of IFN-γ- and IL-4-secreting cells among foals. Fifty-nine foals were randomly assigned to 2 treatment groups (IPPVO or placebo) prior to birth. At 24-48 h of age, foals received 2 ml of either IPPVO or a placebo by intramuscular injection. Injections were repeated 24h and 8 days later. The number of IFN-γ- and IL-4-secreting cells was measured using a validated ELISPOT assay on blood mononuclear cells coll...
Fikri F, Hendrawan D, Wicaksono AP, Purnomo A, Khairani S, Chhetri S, Maslamama ST, Purnama MTE.Colic is among the common health issues in equine health management. Gastrointestinal (GI) disorders are the most frequent causes of colic, but dysfunction of other organs and systems inside the abdominal cavity may also contribute. Therefore, it is crucial to identify risk factors for colic of specific etiologies. This study aimed to examine the incidence, risk factors, and best therapeutic management practices for horses with colic. Unassigned: A cohort of 256 horses living in Lamongan, East Java, Indonesia, was randomly recruited based on reports of colic symptoms by owners. Diagnosis and t...
Slusarewicz P, Slusarewicz JH, Nielsen MK.An automated equine fecal egg count test, known as the Parasight System, was modified for use with small ruminants. Modifications included the introduction of a short centrifugation step in a floatation medium, an adjustment in pre-test sample filtering, and training of an image analysis-based egg counting algorithm to recognize and enumerate trichostrongylid eggs. In preliminary assessments, the modified method produced trichostrongylid egg counts comparable to manual McMaster analyses of the same samples from both ovine and caprine sources. The coefficient of determination (R) for the linear...
Dale B, Brown R, Miller J, White RT, Air GM, Cordell B.Equine influenza is caused by two serotypes of type A influenza virus, EIV-A1 and EIV-A2. The complete nucleotide sequence of the neuraminidase (NA) genes of both the A1 (N7 subtype) and A2 (N8 subtype) serotype has been determined following cloning of full-length viral NA cDNAs into pBR322. Analysis of the deduced amino acid sequences reveals that the N7 and N8 genes share expected extensive homologies with the previously sequenced N1, N2, and N9 NA subtypes. These homologies include conservation of basic NA gene and protein structure, cysteine residues, potential glycosylation sites, and res...
Rush BR, Sanderson MW, Elmore RG.The purpose of this study was to assess pre-matriculation academic and demographic data to identify risk factors for academic difficulty and failure to graduate among veterinary students. Admissions data were compiled for 1,098 students admitted to veterinary college between 1989 and 2000 inclusive. Students were classified by (a) academic success, consisting of students who completed veterinary school within four years in the top 90% of the class or (b) academic difficulty, including students dismissed for academic reasons, students who experienced academic delay, and students who graduated w...
Demyda-Peyrás S, Laseca N, Anaya G, Kij-Mitka B, Molina A, Karlau A, Valera M.Chromosomal abnormalities are largely associated with fertility impairments in the domestic horse. To date, over 600 cases of individuals carrying abnormal chromosome complements have been reported, making the domestic horse the species with the highest prevalence. However, studies analyzing the prevalence of chromosomal diseases in whole populations are scarce. We, therefore, employed a two-step molecular tool to screen and diagnose chromosomal abnormalities in a large population of 25,237 Pura Raza Español horses. Individuals were first screened using short tandem repeats parentage testing ...
Madrigal-Valencia TL, Saavedra-Montañez M, Pérez-Torres A, Hernández J, Segalés J, Hernández YD, Candanosa-Aranda IE, Pérez-Guiot A....Ovine gammaherpesvirus 2 (OvHV-2), a member of the genus Macavirus, causes sheep-associated malignant catarrhal fever (SA-MCF), a fatal lymphoproliferative disease affecting a wide variety of ungulates in addition to horses. This study described an outbreak of SA-MCF in Mexico and the identification of the OvHV-2 virus in primary rabbit testis cultures through the generation of intranuclear inclusion bodies, syncytia, immunofluorescence (IF), immunocytochemistry (ICC), immunohistochemistry (IHC), endpoint polymerase chain reaction (PCR), and partial sequencing of the ORF75 gene. The animals in...
Traversa D, Otranto D, Iorio R, Giangaspero A.Equine thelaziosis caused by the eyeworm Thelazia lacrymalis is a parasitic disease transmitted by muscid flies. Although equine thelaziosis is known to have worldwide distribution, information on the epidemiology and presence of the intermediate hosts of T. lacrymalis is lacking. In the present work, a PCR-RFLP based assay on the first and/or second internal transcribed spacer (ITS1 and ITS2) of ribosomal DNA was developed for the detection of T. lacrymalis DNA in its putative vector(s). The sensitivity of the technique was also assessed. The restriction patterns obtained readily differentiat...
Keane DP, Little PB, Wilkie BN, Artsob H, Thorsen J.A survey was conducted by testing 115 paired equine serum and cerebrospinal fluid samples by hemagglutination-inhibition for antibodies to Powassan and snowshoe hare viruses, and by virus neutralization for antibodies to equine herpesvirus type 1. Twenty-five samples were from horses with spontaneous neurological disease and the remainder from horses euthanized because of various nonneurological disorders. All sera and cerebrospinal fluids were negative for antibodies to Powassan virus. Fifty-one sera (44.3%) and 15 cerebrospinal fluids (13.0%) had antibodies to snowshoe hare virus. Ninety-eig...
Nunes JDSDSS, Casseb LMN, Guimarães RJPS, Reis WDM, de Barros BCV, Ferreira MS, Chiang JO, Pinheiro HHC, Vasconcelos PFDC, Cruz ACR.Serum samples from 89 equids were analyzed (75 horses, 9 donkeys, and 5 mules) from the municipality of Viseu, Pará state, Brazil. Samples were collected in November 2014 and August 2015. The antibody prevalence against the following alphaviruses was estimated: Eastern equine encephalitis virus, Western equine encephalitis virus, Mucambo virus, and Mayaro virus. Seroprevalence was determined by the hemagglutination inhibition (HI) technique. Sera that exhibited HI antibodies with heterotypic reactions for the analyzed viruses were subjected to the 90% plaque reduction neutralization test (PRN...
Thompson JA, Brown SE, Riddle WT, Seahorn JC, Cohen ND.To estimate spatial risks associated with mare reproductive loss syndrome (MRLS) during 2001 among horses in a specific study population and partition the herd effects into those attributable to herd location and those that were spatially random and likely attributable to herd management. Animals-Pregnant broodmares from 62 farms in 7 counties in central Kentucky. Methods: Veterinarians provided the 2001 abortion incidence proportions for each farm included in the study. Farms were georeferenced and data were analyzed by use of a fully Bayesian risk-mapping technique. Results: Large farm-to-fa...
Lönnell C, Roepstorff L, Egenvall A.Lameness is the most commonly diagnosed condition in equine veterinary practice. To examine whether variations in management and husbandry strategies in riding schools could influence wastage due to orthopaedic injury schools with high (HUIO) or low (LUIO) insurance claims for orthopaedic injuries (as an indirect measure of wastage) were compared epidemiologically using an extensive questionnaire and field study visits. Schools differed in management strategies and these influence injury rate and longevity. For horses in the LUIO schools a significantly longer time period had elapsed since acq...
Mayo C, Venter E, Steyn J, Coetzee P, van Vuuren M, Crafford J, Schütte C, Venter G.The seasonal abundance of Culicoides midges, the vector of Bluetongue and African horse sickness viruses (BTV/AHSV) and the presence of viruses in midges were determined in 3 geographic areas in South Africa. In the Onderstepoort area, more than 500,000 Culicoides midges belonging to 27 species were collected. Eighteen midge species were collected throughout Winter and the presence of AHSV and BTV RNA in midges was detected using real time reverse transcription quantitative polymerase chain reaction. The nucleic acid of AHSV was found in 12 pools out of total pools of 35 Culicoides. Twenty‑f...
