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.
Ward MP, Ramsay BH, Gallo K.Data from an outbreak (August to October, 2002) of West Nile virus (WNV) encephalomyelitis in a population of horses located in northern Indiana was scanned for clusters in time and space. One significant (p = 0.04) cluster of case premises was detected, occurring between September 4 and 10 in the south-west part of the study area (85.70 degrees N, 45.50 degrees W). It included 10 case premises (3.67 case premises expected) within a radius of 2264 m. Image data were acquired by the Advanced Very High Resolution Radiometer (AVHRR) sensor onboard a National Oceanic and Atmospheric Administration...
Kirisawa R, Hosoi Y, Yamaya R, Taniyama H, Okamoto M, Tsunoda N, Hagiwara K, Iwai H.We isolated a variant equine herpesvirus-1 (EHV-1), strain 5089, from the lung of a dead neonatal foal in Japan and characterized the biological nature of the virus. The virus spread in cultured cells mainly by cell-to-cell infection, unlike wild-type EHV-1, which spreads efficiently as a cell-free virus. The virus titer in cultured supernatant and the intracellular virus titer were low compared to those of wild-type EHV-1. Heparin treatment of the virus had no effect on viral infectivity in cell culture. Glycoprotein C (gC) was not detected by Western blotting and fluorescent antibody tests i...
Perkins NR, Reid SW, Morris RS.To investigate risk factors for injury to musculoskeletal structures of the lower fore- and hind-limbs of Thoroughbred horses training and racing in New Zealand. Methods: A case-control study analysed by logistic regression was used to compare explanatory variables for musculoskeletal injuries (MSI) in racehorses. The first dataset, termed the Training dataset, involved 459 first-occurrence cases of lower-limb MSI in horses in training, and the second, the Starting dataset, comprised a subset of those horses that had started in at least one trial or race in the training preparation that ended ...
Perkins NR, Reid SW, Morris RS.To investigate risk factors for injury to the superficial digital flexor tendon (SDFT) and suspensory apparatus (SA) of the forelimbs in Thoroughbred racehorses in New Zealand. Methods: Poisson and negative binomial regression, with exposure time represented by cumulative training days for each horse, were used to relate explanatory variables to the incidence rate (IR) of cases of inflammation of the SDFT (n=51), and injuries involving the SA (n=48) in a population of 1,571 commercially- trained racehorses over 554,745 study days. Only the first occurrence of an injury for any one horse was el...
Krcmar S, Hribar LJ, Kopi M.The attraction of female tabanids to Malaise traps and canopy traps baited with aged horse urine, 1-octen-3-ol, or a combination of aged horse urine and acetone was studied in the Kopacki rit Nature Park in Eastern Croatia. Malaise traps captured very few tabanids relative to canopy traps. The number of females of Tabanus tergestinus and Haematopotapluvialis collected from 1-octen-3-ol baited canopy traps differed significantly from traps baited with aged horse urine. However, the number of females of Tabanus bromius, Atylotus loewianus, and Tabanus maculicornis collected from canopy traps bai...
Wood JL, Kelly L, Cardwell JM, Park AW.The transmission of contagious equine metritis (CEM) on stud farms in Britain, Ireland and other European countries is prevented by following the recommendations in the Horserace Betting Levy Board's Code of Practice on CEM. A quantitative risk assessment was undertaken to estimate the likely impact of removing the recommendation, from the 2002 code, to culture endometrial or cervical swabs microaerophilically for the presence of Taylorella equigenitalis, the causative organism. The scientific literature was reviewed for evidence about the anatomical distribution of T. equigenitalis at differe...
Fukai K, Saito T, Fukuda O, Hagiwara A, Inoue K, Sato M.In this study, equine group A rotavirus (RV-A), Nasuno, isolated from foal diarrhoea in Tochigi Prefecture, Japan was characterised genetically by sequence analysis of the genome segments encoding VP4 and VP7. The nucleotide and deduced amino acid sequences revealed high homology with P[12] RV-As (94.0-99.3% and 94.9-99.4%) and G3 RV-As (86.9-99.5% and 91.1-99.4%). Nasuno was also classified into P[12] and G3 in the phylogenetic analysis of the nucleotide sequences of the genome segments encoding VP4 and VP7.
Takai S, Sengee S, Madarame H, Hatori F, Yasuoka K, Ochirel E, Sasaki Y, Kakuda T, Tsubaki S, Bandi N, Sodnomdarjaa R.In native Mongolian horses, the incidence and distribution of Rhodococcus equi are poorly understood. One hundred and fourteen equine fecal samples and 71 soil samples were collected from the camp sites of 26 nomadic families located in three areas less than 100 km from Ulaanbaatar, Mongolia. Five fecal samples were also collected from foals of Przewalski's Horses introduced into the Hustai National Park, Mongolia. No R. equi was isolated from the Mongolian horses or the soil samples. However, three colonies of R. equi were isolated from two fecal samples collected from foals of Przewalski's H...
Maeda K, Kai K, Matsumura T.Infection with equine herpesvirus-4 (EHV-4) is a major cause of respiratory tract disease, equine rhinopneumonitis, in horses. Although the full sequence of EHV-4 has been reported, genomic differences among EHV-4 field isolates have not yet been characterized. In this study, the genomic diversity between 23 Japanese EHV-4 isolates was analyzed by digestion with restriction endonucleases (BamHI, BgIII, EcoRI, SacI, and SalI) and polymerase chain reaction (PCR). The restriction endonuclease digestion patterns of the EHV-4 field isolates showed distinct differences which included mobility shifts...
Patel JR, Heldens J.This review concentrates on the epidemiology, latency and pathogenesis of, and the approaches taken to control infection of horses by equine herpesvirus types 1 (EHV-1) and 4 (EHV-4). Although both viruses may cause febrile rhinopneumonitis, EHV-1 is the main cause of abortions, paresis and neonatal foal deaths. The lesion central to these three conditions is necrotising vasculitis and thrombosis resulting from lytic infection of endothelial cells lining blood capillaries. The initiation of infection in these lesions is likely to be by reactivated EHV-1 from latently infected leukocytes. Howev...
Sabeta CT, Randles JL.In July 2003 a 2-year-old Thoroughbred colt was imported from Harare, Zimbabwe to the Ashburton Training Centre, Pietermaritzburg, South Africa. Five months after importation, the colt presented with clinical signs suggestive of rabies: it was uncoordinated, showed muscle tremors and was biting at itself. Brain tissue was submitted for analysis and the clinical diagnosis was confirmed by the fluorescent antibody test and reverse-transcription polymerase chain reaction (RT-PCR). Phylogenetic analysis of the nucleotide sequence of the cytoplasmic domain of the glycoprotein and the G-L intergenic...
Rolão N, Martins MJ, João A, Campino L.The present report describes the first case of equine leishmaniasis in Portugal. Leishmania infection was detected in one animal, which presented an ulcerated skin lesion. Diagnosis was based on serology by CIE, and parasite DNA detection by real-time PCR using a probe specific for L. infantum. This finding requests further leishmaniasis equine surveys in order to clarify the role of the horse as reservoir host in european endemic areas.
O'Brien E, Stevens KB, Pfeiffer DU, Hall J, Marr CM.The aims of this study were to estimate the wastage of horses registered for eventing in Britain, to investigate the reasons for this wastage and to evaluate factors affecting the horses' achievement of grade I status (at least 61 points) while registered. An analysis of the database of the British Eventing register found that 33.7 per cent of horses registered for the first time in 1999 were not re-registered for eventing in subsequent years. By using multivariable logistic regression analysis, it was shown that horses that were kept at an event yard were more likely to be re-registered than ...
Sofronic-Milosavljevic Lj, Ilic N, Djordjevic M, Savic M, Gruden-Movsesijan A, Cuperlovic K, Murrell KD.In the Balkan countries, where trichinellosis is a re-emerging zoonosis, it is of great importance to determine Trichinella infection prevalence among the major hosts, including horses. One method for monitoring prevalence is serological surveillance; however, the validity of serological methods in horses is not well understood. The dynamics of anti-Trichinella IgG production and circulating excretory/secretory (ES) antigens were investigated in three horses experimentally-infected with Trichinella spiralis. Horses were slaughtered at 32 week post infection (p.i.). Low worm burdens were found ...
Greene IP, Paessler S, Austgen L, Anishchenko M, Brault AC, Bowen RA, Weaver SC.Epidemics of Venezuelan equine encephalitis (VEE) result from high-titer equine viremia of IAB and IC subtype viruses that mediate increased mosquito transmission and spillover to humans. Previous genetic studies suggest that mutations in the E2 envelope glycoprotein allow relatively viremia-incompetent, enzootic subtype ID strains to adapt for equine replication, leading to VEE emergence. To test this hypothesis directly, chimeric VEEV strains containing the genetic backbone of enzootic subtype ID strains and the partial envelope glycoprotein genes of epizootic subtype IC and IAB strains, as ...
Hirsbrunner G, Reist M, Couto SS, Steiner A, Snyder J, Vanleeuwen E, Liu I.Uterine smooth muscle specimens were collected from euthanatized mares in estrus and diestrus. Longitudinal and circular specimens were mounted in organ baths and the signals transcribed to a Grass polygraph. After equilibration time and 2 g preload, their physiologic isometric contractility was recorded for a continuous 2.0 h. Area under the curve, frequency and time occupied by contractions were studied. Differences between cycle phases, between muscle layers, and over the recorded time periods were statistically evaluated using linear mixed-effect models. In the mare, physiologic contractil...
Hoane JS, Yeargan MR, Stamper S, Saville WJ, Morrow JK, Lindsay DS, Howe DK.Neospora hughesi is a recently identified cause of equine protozoal myeloencephalitis. However, the significance of this parasite is poorly understood. An enzyme-linked immunosorbent assay (ELISA) with a recombinant form of the N. hughesi 29-kDa surface antigen (rNhSAG1) was developed for serodiagnosis of equine N. hughesi infections. Parallel ELISA analysis showed that animals immunized or infected with N. hughesi exhibited greater antibody reactivity with rNhSAG1 than with the Neospora caninum homolog, rNcSAG1. The rNhSAG1 ELISA showed 94.4% sensitivity and 95.0% specificity when compared wi...
McGuire TC, Fraser DG, Mealey RH.Cytotoxic T lymphocytes (CTL) are associated with virus control in horses infected with equine infectious anemia virus (EIAV). Early in infection, control of the initial viremia coincides with the appearance of CTL and occurs before the appearance of neutralizing antibody. In carrier horses, treatment with immunosuppressive drugs results in viremia before a change in serum neutralizing antibody occurs. Clearance of initial viremia caused by other lentiviruses, including human immunodeficiency virus-1 and simian immunodeficiency virus, is also associated with CTL and not neutralizing antibody. ...
Kapel CM, Webster P, Gamble HR.Only a few studies have compared the muscle distribution of the different Trichinella genotypes. In this study, data were obtained from a series of experimental infections in pigs, wild boars, foxes and horses, with the aim of evaluating the predilection sites of nine well-defined genotypes of Trichinella. Necropsy was performed at 5, 10, 20 and 40 weeks post inoculation. From all host species, corresponding muscles/muscle groups were examined by artificial digestion. In foxes where all Trichinella species established in high numbers, the encapsulating species were found primarily in the tongu...
Mullaney T, Murphy AJ, Kiupel M, Bell JA, Rossano MG, Mansfield LS.Opossums (Didelphis spp.) are the definitive host for the protozoan parasite Sarcocystis neurona, the causative agent of equine protozoal myeloencephalitis (EPM). Opossums shed sporocysts in feces that can be ingested by true intermediate hosts (cats, raccoons, skunks, armadillos and sea otters). Horses acquire the parasite by ingestion of feed or water contaminated by opossum feces. However, horses have been classified as aberrant intermediate hosts because the terminal asexual sarcocyst stage that is required for transmission to the definitive host has not been found in their tissues despite...
Yanoviak SP, Aguilar PV, Lounibos LP, Weaver SC.Venezuelan equine encephalitis (VEE) complex alphaviruses are serious health threats in the Americas and regularly infect humans living in or near Amazonian rain forests. As part of a larger surveillance program, we placed six hamster-baited mosquito traps in a disturbed white sand forest of northeastern Peru for 3 d. Virus isolations from hamster serum and trapped mosquito pools demonstrated that a VEE subtype IIIC alphavirus was transmitted to a hamster by the mosquito Culex (Melanoconion) gnomatos Sallum, Hutchings & Ferreira. This species, like the other seven proven VEE complex alphavirus...
Claes F, Ilgekbayeva GD, Verloo D, Saidouldin TS, Geerts S, Buscher P, Goddeeris BM.In this study, we compared the complement fixation test (CFT), the horse complement fixation test (HCFT) and a card agglutination test for trypanosomosis (CATT/T. evansi) for the diagnosis of equine trypanosomosis in the Republic of Kazakhstan. Cohen's kappa test was used to evaluate the concordance between the three tests. Kappa scores for CFT versus HCFT and CATT are both 0.6165 (95% Confidence Interval CI 0.414--0.819) indicating a "substantial" agreement between CFT and HCFT or CATT, respectively. Kappa for HCFT versus CATT is 0.395 (CI 0.142--0.648) indicating a "fair" agreement between t...
Upjohn MM, Archer RM, Christley RM, McGowan CM.A telephone survey of 51 National Hunt racing yards with 1140 horses in training was made in April and May 2003 to establish the incidence of exertional rhabdomyolysis syndrome during the previous year. A case-control study was used to investigate the risk factors for the syndrome in eight yards selected on the basis that cases had been confirmed by the analysis of serum muscle enzymes. The overall incidence of syndrome was 6.1 cases per 100 horses per year, and 55 per cent of the yards reported at least one case. The risk factors identified were sex, the average length of the training gallop,...
Causey RC, Weber JA, Emmans EE, Stephenson LA, Homola AD, Knapp KR, Crowley IF, Pelletier DC, Wooley NA.The purpose of this study was to describe strain-specific immune responses to Streptococcus equi subspecies zooepidemicus (S. zooepidemicus) during uterine infection in horses. Five isolates of S. zooepidemicus were differentiated into four strains antigenically by bactericidal testing in blood of 12 horses, and genetically by pulsed-field gel electrophoresis. Eight healthy mares were then divided into two groups, each inoculated with one strain intrauterinely on three successive oestrous cycles followed by a second strain for three successive cycles, first and second strains being reversed fo...
Murray JK, Singer ER, Morgan KL, Proudman CJ, French NP.The cross-country phase of eventing competitions has been associated with injuries and fatalities to horses and riders. A case-control study was carried out to identify variables that were associated with increased or decreased risk of a horse fall on the cross-country phase at event competitions. After initial analysis, the dataset was split according to the categories of one-day events as compared to two- or three-day events to establish whether significant risk factors varied between the different types of eventing competitions. Data were collected for 121 cases (horse falls) at one-day eve...
Szeredi L, Hotzel H, Sachse K.Seventy-seven cases of equine abortion from 49 Hungarian farms that occurred between 1998 and 2000 were investigated for the presence of chlamydiae by immunohistochemistry, PCR and/or MZN staining. Evidence of the presence of these bacteria was obtained in 64 cases (83.1%) from 41 (83.7%) different farms. Partial ompA gene sequencing of PCR products revealed that the agent was Chlamydophila psittaci. Based on the findings of microbial diagnosis, pathology and case history, chlamydial infection was considered to be the most likely cause of abortion in at least 11 (14.3%) cases. In the remaining...
Shimizu A, Kawano J, Ozaki J, Sasaki N, Kimura S, Kamada M, Anzai S, Saito H, Sato H.Seventy-six Staphylococcus aureus strains isolated from various lesions of horses were characterized. All of the 76 strains were identified as biotypes B (38.2%) and C (61.8%). Of 55 strains tested, 42 (76.4%) were differentiated into 7 coagulase types. Coagulase types V and VII were predominant in the metritis strains. Coagulase type II was found most frequently in the strains from phlegmon, dermatitis, sinusitis, empyema sinus, and nasal catarrh. Forty-two (55.3%) of the 76 strains were differentiated into 24 phage patterns. Twenty (58.8%) of 34 typable strains from metritis were lysed by th...
Dorrego A, Herranz C, Pérez-Sancho M, Camino E, Gómez-Arrones V, Carrasco JJ, De Gabriel-Pérez J, Serres C, Cruz-López F.Taylorella asinigenitalis is a non-pathogenic bacteria isolated from the genital tract of donkeys but also a cause of metritis and vaginal discharge in mares. It is closely related to Taylorella equigenitalis, the cause of Contagious Equine Metritis (CEM) in horses, and has been present in different countries in Europe since 1995. Up to date, there are no studies on the prevalence of T. asinigenitalis in the equine or asinine populations in Spain; this is the first report of the presence of T. asinigenitalis in donkeys (Equus asinus) from different breeds in three regions of Spain. A total of ...
Muraro LS, Nogueira MF, Borges AMCM, Souza AO, Vieira TSWJ, de Aguiar DM.Bacteria of the genus Ehrlichia are transmitted by ticks and also are an important cause of infection in wild and domestic mammals. Infection with Ehrlichia spp. has been reported in horses, especially in the USA, Nicaragua and Brazil. In this study, we report the parasitism by Amblyomma sculptum, Rhipicephalus microplus and Dermacentor nitens ticks in horses from a ranch located in south Pantanal wetland. Molecular and serological analyzes to determine infection by Ehrlichia spp. in horses and their respective ticks were carried out. A total of 12 horses were submitted to blood collection to ...
Dyson S, Brown V, Collins S, Murray R.Associations between degree of ossification of the cartilages of the foot and injuries to other structures of the foot have been suggested, but have not been investigated by large scale studies. Objective: To describe the frequency of grade >3 ossification of the cartilages of the foot (possibly significant ossification, PSO), mediolateral symmetry of ossification and left-right symmetry between feet; and to investigate associations between PSO and injury of either the collateral ligaments (CLs) of the distal interphalangeal (DIP) joint or the distal phalanx. Objective: Possibly significant os...
Siles-Lucas M, Felleisen R, Cuesta-Bandera C, Gottstein B, Eckert J.Swiss and Spanish isolates of Echinococcus granulosus were compared using different molecular biological techniques: Genomic DNAs isolated from parasites originating from various intermediate hosts were subjected to Southern hybridization with different probes, the same source of DNA was used for DNA amplification using the Random Amplified Polymorphic DNA (RAPD) technique. With both methods the various isolates (metacestodes) of E. granulosus exhibited characteristic banding patterns which allowed us to assign them to the following groups of homologous profiles: (a) isolates of horse and donk...
Burkom H, Estberg L, Akkina J, Elbert Y, Zepeda C, Baszler T.The Risk Identification Unit (RIU) of the US Dept. of Agriculture's Center for Epidemiology and Animal Health (CEAH) conducts weekly surveillance of national livestock health data and routine coordination with agricultural stakeholders. As part of an initiative to increase the number of species, health issues, and data sources monitored, CEAH epidemiologists are building a surveillance system based on weekly syndromic counts of laboratory test orders in consultation with Colorado State University laboratorians and statistical analysts from the Johns Hopkins University Applied Physics Laborator...
McCue ME, Valberg SJ.To estimate the prevalence of polysaccharide storage myopathy (PSSM) among Quarter Horses in the United States and evaluate possible relationships between muscle glycogen concentration, turnout time, and exercise level. Methods: Cross-sectional study. Methods: 164 overtly healthy Quarter Horses > 2 years old from 5 states. Methods: Horses with a history of exertional rhabdomyolysis or any other muscular disease were excluded. Muscle biopsy specimens were examined histologically for evidence of PSSM and were submitted for determination of muscle glycogen concentration. A diagnosis of PSSM wa...
Hallamaa RE.Summer eczema, allergic dermatitis of the horse, was studied on 275 affected horses in Finland in 1997-2007. Features of the horses, clinical signs of the disease and owners' opinions of aggravating factors were recorded. Differences, especially, between two of the native Scandinavian horse breeds, the Finnhorse and the Icelandic horse, were evaluated. The study was based on clinical examination and information from the owners. Of the horses, 50% were Finnhorses, 26% Icelandic horses and 24% consisted of different breeds of ponies and other horses. Of the Finnhorses, 76% had summer eczema by t...
Rampacci E, Mazzola K, Beccati F, Passamonti F.Feeding foals with poor quality colostrum predisposes them to failure of passive transfer (FPT). FPT is a major risk factor for neonatal infections. Objective: To assess the optimal cut-offs for the optical (OR) and digital (DR) refractometer and determine their accuracy for poor quality colostrum diagnosis. Methods: A diagnostic validation study. Methods: Eighty-one colostrum samples and sera were collected from broodmares and their neonatal foals, respectively. Colostral and serum IgG concentrations were measured by radial immunodiffusion (RID), DR and OR. Correlation coefficients were calcu...
Dabareiner RM, Cohen ND, Carter GK, Nunn S, Moyer W.To determine the types of musculoskeletal problems that result in lameness or poor performance in horses used for team roping and determine whether these problems are different in horses used for heading versus heeling. Methods: Retrospective study. Methods: 118 horses. Methods: Medical records of team roping horses that were evaluated because of lameness or poor performance were reviewed to obtain information regarding signalment, primary use (ie, head horse or heel horse), history, results of physical and lameness examinations, diagnostic tests performed, final diagnosis, and treatment. Resu...
Leszkowicz Mazuz M, Mimoun L, Schvartz G, Tirosh-Levy S, Savitzki I, Edery N, Blum SE, Baneth G, Pusterla N, Steinman A.In horses, and have been associated with fetal loss, and neurological disease, respectively. This study investigated the role of spp. infection in equine abortion in Israel. The presence of anti- spp. antibodies was evaluated in 31 aborting mares by indirect fluorescent antibody test (IFAT) and the presence of parasite DNA in their aborted fetuses was evaluated by polymerase chain reaction (PCR), using two target loci (ITS1 and Nc5). The seroprevalence found in aborting mares was 70.9% and the prevalence by DNA detection in the aborted fetuses was 41.9%. Transplacental transmission from pos...
Anzai T, Nakanishi A, Wada R, Higuchi T, Hagiwara S, Takazawa M, Oobayashi K, Inoue T.For determination whether strangles has invaded the Hidaka district of Hokkaido, the main racehorse-breeding area of Japan, a epizootiological survey with bacterial isolation was carried out during the breeding season in 1995. Streptococcus equi subsp. equi, which is the causative agent of strangles, was isolated from two Thoroughbred horses with submandibular lymphadenitis. Isolates were identified by serological grouping, biochemical tests and analysis of cell surface proteins by Western immunoblotting. Through this survey, it revealed that S. equi subsp. equi has invaded the Hidaka district...
Bolwell CF, Rosanowski SM, Scott I, Sells PD, Rogers CW.Against a global background of increasing anthelmintic resistance in parasites, little is known about the current parasite control strategies adopted within the equine industry in New Zealand. The aim of the study was to describe and compare the current parasite management and control practices used on Thoroughbred and Standardbred stud farms in New Zealand. An online questionnaire was used to collect data on the demographics of respondents, parasite control methods, grazing management, and use of faecal egg counts. Questions regarding parasite control strategy, how often horses were dewormed,...
Hitchens PL, Curry B, Blizzard CL, Palmer AJ.The profession of a horse-racing jockey is a dangerous one. We developed a decision tree model quantifying the effects of implementing different safety strategies on jockey fall and injury rates and their associated costs. Methods: Data on race-day falls were obtained from stewards' reports from August 2002 to July 2009. Insurance claim data were provided by Principal Racing Authorities and workers' compensation authorities in each jurisdiction. Fall and claim incidence data were used as baseline rates. The model considered (1) the status quo, in which policy was unchanged; and (2) compared it...
Equine infectious anaemia (EIA) is a blood borne disease that is listed among the notifiable diseases of the World Organisation for Animal Health (OIE). EIA is also regulated by the OIE for the international trading provisions and is generally subject to control programmes. Since 2011, Italy has been conducting a surveillance plan based on a three-tier diagnostic system, using a serological ELISA as screening test, an agar gel immunodiffusion test (AGIDT) as a confirmatory method, and an immunoblot (IB) as an alternative confirmatory assay for discordant results between the first two tests. As...
Nielsen MK, Vidyashankar AN, Hanlon BM, Diao G, Petersen SL, Kaplan RM.Anthelmintic resistance is an increasing challenge for the control of equine parasites. The fecal egg count reduction test (FECRT) is the practical gold standard method for evaluating reduction in anthelmintic efficacy, but the interpretation is complicated due to high levels of variability. A hierarchical statistical model was described for analysis of FECRT data from multiple farms to evaluate the role of biological factors in determining the strongyle efficacy of pyrantel pamoate in a study performed in Denmark. The model was then used to describe two notions of farm efficacy, namely condit...
Costa PWLD, Vilela VLR, Feitosa TF.The objective of this study was to determine the parasitological profiles of traction equids from the semi-arid climate of Paraíba (PB) State. We analyzed 96 equids that performed traction work, with no defined breed, males and females, and all older than 24 months. Among the analyzed animals, 51% were donkeys, 41.7% mules, and 7.3% horses. Fecal material and blood were collected for parasitological examination and to determine the packed cell volume (PCV), respectively. The samples were sent to the Veterinary Parasitology Laboratory, Veterinary Hospital - IFPB, Sousa-PB campus, and epidemiol...
Fassil H, El Harrak M, Marié JL.Morocco has undergone three outbreaks of West Nile fever. The first, in 1996, began with a case in a horse herd in Benslimane (central region) and spread to neighboring cities (in the central and northwestern regions). The next two outbreaks appeared after identical 7-year epidemiological latency periods (in 2003 and 2010) in the same area and season. The only human case, which was fatal, occurred during the 1996 outbreak. The West Nile virus strains circulating in Morocco are closely related to other western Mediterranean strains and are characterized by high virulence in horses.
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...
Shin JA, Yang YH, Kim HS, Yun YM, Lee KK.The study was carried out to investigate the genetic polymorphism of the serum proteins of horses in Cheju. They were assigned to three groups; 45 Cheju native horses(CNH), 60 Cheju racing horses(CRH) and 60 Thoroughbreds(TB). We analyzed the phenotypes and gene frequencies of serum proteins which were albumin (Alb), vitamin-D binding protein(GC), esterase (ES), A1B glycoprotein(A1B) and transferrin(TF) loci using horizontal polyacrylamide gel electrophoresis (HPAGE). All of the loci, except A1B in TB, showed polymorphisms and different allelic and phenotypic frequencies in all three groups. E...
Barker SC.Hendra virus is a new virus of the family Paramyxoviridae. This virus was first detected in Queensland, Australia, in 1994; although, it seems that the virus has infected fruit-eating bats (flying-foxes) for a very long time. At least 2 humans and 15 horses have been killed by this virus since it first emerged as a virus that may infect mammals other than flying-foxes. Hendra virus is thought to have moved from flying-foxes to horses, and then from horses to people. There is a reasonably strong hypothesis for horse-to-human transmission: transmission of virus via nasal discharge, saliva and/or...
Singer ER, Saxby F, French NP.Serious injuries to horses and riders in horse trials (HT) and three-day events (3DE) are usually associated with falls of horses, which invariably involve falls of the riders. Many potential causes for these falls have been discussed. Objective: The aim of this case-control study was to investigate the risk factors for horse falls on the cross-country phase of horse trials and three-day events. Methods: Using retrospective data, significant risk factors identified with unvariable analysis (P value <0.2) were entered into a multivariable logistic regression model. Significant risk factors (...
Proietto LR, Plummer CE, Maxwell KM, Lamb KE, Brooks DE.The purpose of this investigation was to identify potential environmental risk factors for the diagnosis of equine deep stromal abscesses (DSA) in the subtropical climate at the University of Florida Veterinary Medical Center (UFVMC). Methods: Cases included were selected from the UFVMC medical record and imaging database, and included all cases of equine DSA diagnosed during the period from December 1991 to December 2013 in patients residing in north central Florida. Patient date of diagnosis and atmospheric data was obtained for north central Florida for the corresponding time period. Univar...
Fletcher WO, Stallknecht DE, Jenney EW.Seventeen species of mammals and seven species of birds from Ossabaw Island, Georgia, were tested for vesicular stomatitis (VS) neutralizing antibodies. Seropositive results were restricted to mammals with six of 17 species testing seropositive for VS (New Jersey type) neutralizing antibodies. Seropositive species included: raccoons (Procyon lotor), white-tailed deer (Odocoileus virginianus), feral swine (Sus scrofa), cattle (Bos taurus), horses (Equus caballus), and donkeys (Equus asinus). All tests for VS (Indiana type) were negative.
Pelzel-McCluskey AM.Vesicular stomatitis (VS) is a vector-borne livestock disease caused by either VS New Jersey virus or VS Indiana virus. The disease circulates endemically in northern South America, Central America, and Mexico and only occasionally causes outbreaks in the United States. During the past 20 years, VS outbreaks in the southwestern and Rocky Mountain regions occurred periodically with incursion years followed by virus overwintering and subsequent expansion outbreak years. Regulatory response by animal health officials prevents spread from lesioned animals and manages trade impacts. Recent US outb...
Sallé G, Canlet C, Cortet J, Koch C, Malsa J, Reigner F, Riou M, Perrot N, Blanchard A, Mach N.The widespread failure of anthelmintic drugs against nematodes of veterinary interest requires novel control strategies. Selective treatment of the most susceptible individuals could reduce drug selection pressure but requires appropriate biomarkers of the intrinsic susceptibility potential. To date, this has been missing in livestock species. Here, we selected Welsh ponies with divergent intrinsic susceptibility (measured by their egg excretion levels) to cyathostomin infection and found that their divergence was sustained across a 10-year time window. Using this unique set of individuals, we...
Carmalt JL, Borg H, Näslund H, Waldner C.The aim of this study was to determine whether horses with a proximal palmar/plantar first phalangeal osteochondral fragment (POF) had comparable racing careers (prior to and following surgery) to horses without this fracture. A retrospective cohort study included 174 Swedish Standardbred trotters with osteochondral fragmentation in the palmar/plantar fetlock joint and 613 radiographically negative control horses presented for prepurchase examinations. Medical records and radiographs were examined for each horse. Racing data were retrieved from online Swedish Standardbred harness racing record...
Martineau M, Castagnet S, Kokabi E, Tricot A, Jaÿ M, Léon A, Tardy F.Bacteria belonging to the genus Mycoplasma are small-sized, have no cell walls and small genomes. They commonly cause respiratory disorders in their animal hosts. Three species have been found in the respiratory tract of horses worldwide, that is., Mycoplasma (M.) equirhinis, M. pulmonis and M. felis, but their role in clinical cases remains unclear. Objective: The aim of this study was to i) develop and validate tools to detect, isolate and identify different Mycoplasma spp. strains in clinical equine respiratory-tract specimens and ii) subsequently define the prevalence of the three species ...
Wilkins CA, Richter MB, Hobbs WB, Whitcomb M, Bergh N, Carstens J.The annual incidence of tetanus in the RSA is up to 300 cases with more than 50% of these coming from Natal/KwaZulu. The condition of playing fields and the excretion of Clostridium tetani by horses was therefore investigated. The overall contamination rate of soils in the Durban area is lower than that of published data from other parts of the world, for instance 28% for Durban in comparison with 31-42% for Japan and Quebec. A rugby field in the Transvaal showed 40% contamination and a pasture used for horses for more than 20 years 65%. No case of human or equine tetanus has ever been reporte...
Knowles EJ, Mair TS, Butcher N, Waller AS, Wood JL.Thirty horses with no external signs of strangles were tested for exposure to Streptococcus equi subspecies equi (S equi) using a new, commercially available serological test. The horses were also tested for persistent carriage of S equi by endoscopy of the guttural pouches and PCR analysis of lavage samples. The owners were questioned about the recent medical history of the horses. Serology suggested that four horses had been recently exposed to S equi. None of the horses had a known history of strangles but three of the four seropositive horses had recently shown non-specific signs of respir...
