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.
Degeling C, Gilbert GL, Annand E, Taylor M, Walsh MG, Ward MP, Wilson A, Johnson J.Hendra virus (HeV) infection is endemic in Australian flying-fox populations. Habitat loss has increased the peri-urban presence of flying-foxes, increasing the risk of contact and therefore viral 'spillovers' into horse and human populations. An equine vaccine is available and horse-husbandry practices that minimize HeV exposure are encouraged, but their adoption is suboptimal. Ecological approaches-such as habitat creation and conservation-could complement vaccination and behavioural strategies by reducing spillover risks, but these are controversial. We convened three community juries (two ...
Sconza S, Di Cesare A, Iorio R, Bartolini R, Paoletti B, Traversa D.Cyathostomins, or 'small strongyles', are the most important equine helminths because of their worldwide distribution, spread of anthelmintic‑resistant populations, and pathogenic impact. The so‑called 'selective treatment' of those animals exceeding a certain faecal egg count (FEC) has recently been proposed to implement cyathostomin control programmes. The present study evaluated the extent of egg shedding in 475 horses living in 12 farms from 3 regions of Italy. All examined farms and 224 horses (47.6%...
Pyles MB, Fowler AL, Bill VT, Harlow BE, Crum AD, Hayes SH, Flythe MD, Lawrence LM.Adult horses depend on the microbial community in the hindgut to digest fiber and produce short-chain fatty acids that are use for energy. Colonization of the foal gastrointestinal tract is essential to develop this symbiosis. However, factors affecting colonization are not well understood. The objectives of this study were to evaluate the age-related changes and effects of maternal diet on select fecal bacterial groups in foals from 1 to 28 d of age. Thoroughbred foals ( = 18) were from dams fed forage and one of two concentrates: an oat-based (OB) or corn and wheat middlings-based (CWB) pell...
Dauvillier J, Ter Woort F, van Erck-Westergren E.Fungi contribute to the inflammatory response of lungs in horses with recurrent airway obstruction and in some forms of asthma in humans. The role of fungi in inflammatory airway disease (IAD) has not been assessed. Objective: Evaluate the prevalence of fungi in the respiratory samples of horses diagnosed with IAD, describe clinical signs associated with the presence of fungi in respiratory samples, and assess the risk factors associated with IAD and with the presence of fungi in the airways. Methods: Seven-hundred thirty-one active horses referred to a specialized ambulatory practice for sign...
Huber L, Giguère S, Slovis NM, Carter CN, Barr BS, Cohen ND, Elam J, Erol E, Locke SJ, Phillips ED, Smith JL.The objective of this study was to determine the prevalence of strains resistant to macrolides and rifampin over time in clinical samples from foals submitted to diagnostic laboratories in central Kentucky. We performed a retrospective observational study of all clinical samples from foals that were submitted to veterinary diagnostic laboratories in Kentucky between January 1995 and December 2017. Samples were included if the bacterium was cultured and tested for susceptibility to erythromycin or rifampin. susceptibility testing to erythromycin was available for 2,169 isolates of , while s...
McCoy AM, Smith RL, Secor EJ, Roady PJ.To determine the influence of tissue preparation and long-term storage methods on structural integrity and risk of bacterial contamination of equine amnion. Methods: Prospective experimental investigation SAMPLE POPULATION: Amniotic membranes from 8 healthy mares (n = 440 tested samples). Methods: Samples for baseline bacteriology and histology were taken after removal of debris. The remaining tissue was divided and processed with 0.05% chlorhexidine or 2% iodine/0.25% acetic acid. Processed amnion samples were assigned to 1 of 9 combinations of storage media (saline, chlorhexidine, acetic...
Naves JHFF, Oliveira FG, Bicalho JM, Santos PS, Machado-de-Ávila RA, Chavez-Olortegui C, Leite RC, Reis JKP.Equine infectious anemia (EIA) is a disease caused by a Lentivirus that is currently controlled exclusively by identification of seropositive animals. In most countries, including Brazil, the official diagnostic test for EIA is the agar gel immunodiffusion test (AGID). Although this assay has a high specificity it can produce false negative reactions or equivocal results due to weak precipitation lines, especially in samples from donkeys, mules or newly infected equids. In this pioneering study, it was used overlapping synthetic peptide pools to map and identify a consensus, widely recognised ...
Bannai H, Nemoto M, Tsujimura K, Yamanaka T, Kokado H, Kondo T.In order to establish an efficient system for serological diagnosis of equine viral arteritis in Japan, we compared enzyme-linked immunosorbent assays (ELISAs) provided by two manufacturers (Nisseiken Co., Ltd., Tokyo, Japan, and VMRD Inc., Pullman, WA, U.S.A.) by testing a series of horse sera. The results revealed that 159 of 160 virus-neutralizing (VN) antibody-positive serum samples were positive in both the Nisseiken-ELISA and VMRD-ELISA. Of the VN-negative sera (n=157), 134 and 154 samples were negative in the Nisseiken-ELISA and VMRD-ELISA, respectively. Sensitivity was 99.4% for both t...
Peters-Kennedy J, Lange CE, Rine SL, Hackett RP.Equus caballus papillomavirus 8, a recently discovered virus, has been reported to cause generalised papillomavirus in horses. Objective: To describe a case in which multiple viral plaques, viral papillomas, squamous cell carcinoma (SCC) in situ and invasive squamous cell carcinoma (ISCC) were associated with EcPV8 in a horse. Methods: Case report. Methods: A 16-year-old mixed breed horse presented with dozens of raised crusted papular to nodular lesions over a course of 4 years. Masses had been surgically excised four times and cisplatin beads and emulsion were implanted on three different ...
Robb LL, Hartman DA, Rice L, deMaria J, Bergren NA, Borland EM, Kading RC.Western equine encephalitis (WEE) was once prevalent and routinely isolated from mosquitoes in Colorado; however, isolations of Western equine encephalitis virus (WEEV) have not been reported from mosquito pools since the early 1990s. The objective of the present study was to test pools of Culex tarsalis (Coquillett) mosquitoes sampled from Weld County, CO, in 2016 for evidence of WEEV infection. Over 7,000 mosquitoes were tested, but none were positive for WEEV RNA. These data indicate that WEEV either was not circulating enzootically in Northern Colorado, was very rare, and would require muc...
Brosnahan MM, Al Abri MA, Brooks SA, Antczak DF, Osterrieder N.Equine herpesvirus type 1 (EHV-1)-induced myeloencephalopathy (EHM) is a neurologic disease of horses that represents one outcome of infection. The neurologic form of disease occurs in a subset of infected horses when virus-induced endothelial cell damage triggers vasculitis and subsequent ischemic insult to the central nervous system. EHM causes considerable animal suffering and economic loss for the horse industry. Virus polymorphisms have been previously associated with disease outcome but cannot fully explain why only some horses develop EHM. This study investigated the role of host geneti...
Krajaejun T, Kittichotirat W, Patumcharoenpol P, Rujirawat T, Lohnoo T, Yingyong W.The oomycete Pythium insidiosum infects humans and animals worldwide, and causes the life-threatening condition, called pythosis. Most patients lose infected organs or die from the disease. Comparative genomic analyses of different P. insidiosum strains could provide new insights into its pathobiology, and can lead to discovery of an effective treatment method. Several draft genomes of P. insidiosum are publicly available: three from Asia (Thailand), and one each from North (the United States) and Central (Costa Rica) Americas. We report another draft genome of P. insidiosum isolated from Sout...
Pinidiyapathirage J, Kitchener S, McNamee S, Wynter S, Langford J, Doyle A, McMahon A.Agricultural industries are among the most dangerous in Australia posing significant public health risks. This study analyses the nature and management of agriculture-related injuries presenting to EDs in selected hospitals in Southern Queensland. Data on agricultural injury presentations over a 6 month period was collected at four rural hospitals by a dedicated onsite hospital data coordinator. Additionally, in two of the participating hospitals all injury presentations over the same 6 month period were recorded. A pre-tested survey instrument, modified for rural settings and designed and dev...
Kwak ML, Schubert J.Although forensic parasitology remains in its infancy compared with more developed fields like forensic entomology, parasites can be useful forensic indicators. We present the case of an individual who disobeyed animal health legislation and crossed animal quarantine boundaries and two state lines with a cattle tick (Rhipicephalus australis) infested horse. Following recognition of the infestation by animal health officers, the individual asserted that the infestation had occurred either during transport or upon arrival at the site of discovery, and that they had not contravened quarantine leg...
Hendrickson EHS, Lykkjen S, Dolvik NI, Olstad K.Young Standardbred horses frequently develop fragments in joints. Some fragments represent osteochondrosis; others are considered developmental, but it is uncertain whether they result from preceding osteochondrosis. Osteochondrosis occurs as a consequence of failure of the cartilage canal blood supply and ischaemic chondronecrosis. In heritably predisposed foals, failure was associated with incorporation of vessels into bone. However, bacterial vascular failure was also recently documented in foals suffering spontaneous infections, proving that bacteria can cause osteochondral lesions in foal...
Tomlinson JE, Tennant BC, Struzyna A, Mrad D, Browne N, Whelchel D, Johnson PJ, Jamieson C, Löhr CV, Bildfell R, McKenzie EC, Laverack M, Renshaw RW....A novel equine parvovirus (EqPV-H) was recently discovered in the equine liver with Theiler's disease. Objective: To determine the prevalence of EqPV-H infection in naturally occurring Theiler's disease cases and in-contact horses in the absence of historical equine biologic product administration. Methods: Ten cases of Theiler's disease from 6 separate properties were included in the study, based on the criteria of acute onset of clinical signs of liver failure with laboratory or histopathologic findings characteristic of Theiler's disease and no history of receiving an equine biologic produc...
Delph KM, Beard LA, Trimble AC, Sutter ME, Timoney JF, Morrow JK.Streptococcus equi subspecies equi infection elicits M protein antibody titers in equids. Interpretation of titers is not generally accepted. Objective: The magnitude of S. equi M protein (SeM) antibody titer after infection (titer ≥1:12 800) will be useful to monitor for the presence of complications or the risk of development of complications. Methods: Forty-eight horses on 1 farm involved in strangles outbreak. Methods: Clinical and observational study. S. equi M protein antibody titers were measured on all horses 8 weeks after infection and select horses 12 and 28 weeks after infecti...
Verdon M, Lanz S, Rhyner C, Gerber V, Marti E.Genetic, epidemiologic, and clinical evidence suggests that, in horses, there are manifestations of hypersensitivity that can occur together. Objective: To investigate whether concurrent insect bite hypersensitivity (IBH) and severe equine asthma (EA) is associated with higher allergen-specific and total serum immunoglobulin E (IgE) concentrations than only EA or IBH. Methods: Healthy control horses (C, n = 40), horses with IBH (IBH, n = 24), severe EA (EA, n = 18), and both conditions (IBH/EA, n = 23) were included. Methods: In our retrospective comparative study, sera from ho...
Tomlinson JE, Kapoor A, Kumar A, Tennant BC, Laverack MA, Beard L, Delph K, Davis E, Schott Ii H, Lascola K, Holbrook TC, Johnson P, Taylor SD....Three flaviviruses (equine pegivirus [EPgV]; Theiler's disease-associated virus [TDAV]; non-primate hepacivirus [NPHV]) and equine parvovirus (EqPV-H) are present in equine blood products; the TDAV, NPHV, and EqPV-H have been suggested as potential causes of serum hepatitis. Objective: To determine the prevalence of these viruses in horses with equine serum hepatitis. Methods: Eighteen horses diagnosed with serum hepatitis, enrolled from US referral hospitals. Methods: In the prospective case study, liver, serum, or both samples were tested for EPgV, TDAV, NPHV, and EqPV-H by PCR. Results: Bot...
Cole SD, Stefanovski D, Towl S, Boyle AG.There is a lack of epidemiological studies about equine subsolar (hoof) abscesses even though they are among one of the most common causes of acute, severe lameness. The goals of this study were to (1) describe the equine subsolar abscess patient population of the University of Pennsylvania's New Bolton Center's Field Service and (2) to determine the factors that are associated with increased veterinary visits, prolonged treatment and complications. Descriptive statistics were performed on data collected from 160 cases of equine subsolar abscess. Inferential statistics were performed on a subs...
Cárdenas NC, Galvis JOA, Farinati AA, Grisi-Filho JHH, Diehl GN, Machado G.Glanders is a highly infectious zoonotic disease caused by Burkholderia mallei. The transmission of B. mallei occurs mainly by direct contact, and horses are the natural reservoir. Therefore, the identification of infection sources within horse populations and animal movements is critical to enhance disease control. Here, we analysed the dynamics of horse movements from 2014 to 2016 using network analysis in order to understand the flow of animals in two hierarchical levels, municipalities and farms. The municipality-level network was used to investigate both community clustering and the bala...
Matczuk AK, Skarbek M, Jackulak NA, Bażanów BA.Equid alphaherpesvirus 1 (EHV-1) is one of the main infectious causative agents of abortion in mares and can also be associated with stillbirth, neonatal foal death, rhinopneumonitis in young horses and a neurological disorder called equine herpesvirus myeloencephalopathy (EHM). The neuropathogenicity of the virus was shown to be significantly higher in EHV-1 strains that carry a single nucleotide point (SNP) mutation in the ORF30, which encodes a catalytic subunit of viral DNA polymerase (ORF30 D). Another gene, ORF68 is frequently used for phylogenetic analysis of EHV-1. 27 EHV-1 strains iso...
Ebrahimi M, Hamidinejat H, Tanabandeh MR, Razi Jalali MH, Rasouli A.Diversity among the pathogenic strains of Theileria equi (T. equi), a major agent of equine piroplasmosis, can affect the appropriate detection of parasite and host immunization. Production of recombinant surface proteins from an infected horse in natural endemic area provides a reliable tool for immunodiagnosis of parasite. Regarding this, the present study was targeted toward the cloning, expression, and purification of the immunogenic regions of equine merozoite antigen 1 (EMA-1 gene), as one of the most important immunodominant surface proteins in T. equi, from naturally infected horses in...
Hitchens PL, Morrice-West AV, Stevenson MA, Whitton RC.Studies of racehorse injury or fatality in various countries have identified common, and in some cases conflicting, risk factors. We conducted a systematic search of the relevant literature published from 1990 to 2017. Peer-reviewed articles were included if they reported the incidence of fatal or catastrophic musculoskeletal injury (CMI) in Thoroughbred flat races (n=21) or risk factors for CMI (n=65). Pooled effect sizes were estimated using the random-effects DerSimonian-Laird model. The pooled incidence of CMI was 1.17 (95% confidence interval 0.90, 1.44) per 1000 race starts. Almost 300 f...
Sykes BW, Bowen M, Habershon-Butcher JL, Green M, Hallowell GD.To date, risk factors for equine glandular gastric disease (EGGD) have not been described in Thoroughbred racehorses. Objective: To determine management factors associated with EGGD, identify clinical signs in affected horses, and compare these to equine squamous gastric disease (ESGD). Methods: The study was carried out on 109 Thoroughbred racehorses from 8 training yards (3 in the United Kingdom and 5 in Australia). Methods: Gastroscopic examination alongside a questionnaire regarding management, feeding, exercise, and health. Results: Management factors and clinical signs were different for...
Mejia-Pereira S, Perez-Ecija A, Buchanan BR, Toribio RE, Mendoza FJ.Endocrine disorders are common in donkeys. Pituitary pars intermedia dysfunction (PPID) is thought to be a frequent disturbance in donkeys due to their longevity. However, information on PPID dynamic testing in donkeys is lacking. Objective: The objective of this study was to evaluate the previously described guidelines for PPID diagnosis in horses in donkeys with suspicion of PPID. Methods: Prospective experimental study. Methods: Eighty donkeys were evaluated for PPID suspicion based on clinical signs and baseline adrenocorticotropic hormone (ACTH) concentrations. Six mix-breed donkeys (one ...
Pégné JC, Duquesne F, Laugier C, Lequeux G, Petry S.The present study reports the isolation of A. hippocoleae from genital swabs of 15 apparently healthy mares (at least one had an abortion one month earlier) and describes the genotypic and phenotypic characterisation of these strains. The mares were of eight different breeds with a thoroughbred dominance and came from 11 breeding farms located in the French region of Brittany. 16S rRNA gene sequencing confirmed the species' identification by comparing it with reference strain A. hippocoleae CIP 106850. Some degree of natural divergence within A. hippocoleae was observed by 16S rRNA sequencing ...
Theelen MJP, Wilson WD, Byrne BA, Edman JM, Kass PH, Magdesian KG.The study objectives were to provide cumulative antimicrobial susceptibility data at the patient level and to evaluate the effect of initial antimicrobial treatment on survival in foals with sepsis. Foals below 30days of age with a diagnosis of sepsis, confirmed by isolation of bacteria from normally sterile sites on the day of hospital admission, were included. Susceptibility testing was performed using the broth microdilution procedure. In total, 213 foals and 306 bacterial isolates were included. The likelihood of survival for foals from which all bacteria were susceptible to the initial an...
Dubey JP, Kerber CE, Granstrom DE.To determine serologic prevalence of Sarcocystis neurona, Toxoplasma gondii, and Neospora caninum in horses in Brazil. Methods: Prevalence survey. Methods: 101 Thoroughbreds in Brazil. Methods: Blood samples were obtained from horses and tested for serum antibodies against S neurona by use of an immunoblot procedure with culture-derived S neurona merozoites as antigen, and for serum antibodies against T gondii and N caninum by use of a modified agglutination test with formalin-preserved tachyzoites and mercaptoethanol. Results: Antibodies against S neurona and T gondii were detected in 36 and ...
Proudman CJ, Edwards GB.Faeces samples from 116 horses with colic and 115 non-colic cases were assayed by a centrifugation/floatation method for the presence of tapeworm eggs. Analysis of these data failed to demonstrate an association between tapeworm infection and colic of all types. The data were further analysed according to anatomical site of the lesion causing colic. The risk of ileocaecal colic was increased in the presence of tapeworms. Age, breed and sex were evaluated as possible confounding factors but had no association with the incidence of colic. This study suggests an association between tapeworms and ...
Richt JA, Grabner A, Herzog S.Borna disease is a sporadically occurring, progressive viral polioencephalomyelitis that primarily affects horses and sheep. The etiological agent, Borna disease virus (BDV), is an enveloped, single-stranded RNA virus that has been classified in the new virus family Bornaviridae within the order Mononegavirales. Serological evidence of BDV infection has been found in an increasing number of countries throughout the world. After an incubation period lasting a few weeks to several months, BDV infection can cause locomotor and sensory dysfunction followed by paralysis and death. Borna disease is ...
Guillaume-Vasselin V, Lemaitre L, Dhondt KP, Tedeschi L, Poulard A, Charreyre C, Horvat B.Hendra virus (HeV) is an emerging zoonotic pathogen, which causes severe respiratory illness and encephalitis in humans and horses. Since its first appearance in 1994, spillovers of HeV from its natural reservoir fruit bats occur on almost an annual basis. The high mortality rate in both humans and horses and the wide-ranging reservoir distribution are making HeV a serious public health problem, especially for people exposed to sick horses. This study has aimed to develop an efficient low-cost HeV vaccine for horses based on Canarypox recombinant vector expressing HeV glycoproteins, attachment...
Elia G, Decaro N, Martella V, Campolo M, Desario C, Lorusso E, Cirone F, Buonavoglia C.A real-time PCR assay was developed for detection and quantitation of equid herpesvirus type 1 (EHV-1). The sensitivity of the assay was compared with an established nested-PCR (n-PCR). The real-time PCR detected 1 copy of target DNA, with a sensitivity 1 log higher than gel-based n-PCR. The assay was able to detect specifically EHV-1 DNA in equine tissue samples and there was no cross-amplification of other horse herpesviruses. Real-time PCR was applied to determine EHV-1 load in tissue samples from equine aborted fetuses. The high sensitivity and reproducibility of the EHV-1-specific fluorog...
Cho HC, Hwang S, Kim EM, Park YJ, Shin SU, Jang DH, Chae JS, Choi KS. is an obligate intracellular zoonotic bacterium with a global distribution. This study was conducted to investigate the prevalence of in different animals and to assess the potential role of these species as reservoirs of infection and transmission to humans. A total of 592 blood samples (105 beef cattle, 61 dairy cattle, 110 Korean native goats, 83 Boer goats, and 233 horses) were collected in the Republic of Korea (ROK). The DNA was detected from blood samples using the transposon-like repetitive region () by PCR method. The results showed that 22.7% of the Korean-native goats, 16.4% of t...
van Duijkeren E, Wannet WJ, Heck ME, van Pelt W, Sloet van Oldruitenborgh-Oosterbaan MM, Smit JA, Houwers DJ.We studied 232 Salmonella strains from horses with salmonellosis in The Netherlands, isolated in the period from 1993 to 2000 in order to provide insight in the dynamics of sero-, phage types (pt) and antibiotic susceptibilities over time. The strains were tested for susceptibility to seven antimicrobial agents using the agar diffusion method. In addition, the isolates were sero typed and Salmonella enterica subspecies enterica Typhimurium and Enteritidis strains were further phage typed. S. Typhimurium strains of phage type 506 and 401 (both classified as DT 104 in the English phage typing sy...
Greiner EC, Fadok VA, Rabin EB.Nine species of Culicoides were aspirated from horses in Florida during the second phase of a study of equine Culicoides hypersensitivity (CHS). Approximately 90% of the 2933 midges were Culicoides insignis Lutz, 4% were C.stellifer (Coquillett), 3% were C.niger Root and Hoffman, 2% were C.alachua Jamnback and Wirth and the remaining 1% included C.venustus Hoffman, C.scanloni Wirth and Hubert, C.lahillei Iches (= C.debilipalpis Lutz), C.pusillus Lutz, and C.edeni Wirth and Blanton. Culicoides were sampled on seven farms located throughout Florida. The location and seasonality of lesion develop...
Mellor PS.1. 903 horses were examined at 3 abattoirs in South East England. 10(22–7%) of the horses at the London Colney abattoir, 23(13–9%) of those at the Braintree abattoir, Essex, and 90(12–9%) of those at the Islington abattoir, London, were infected with O. cervicalis. All 105 horses examined in Southern Ireland were found to be negative.
2. The adult worms of O. cervicalis were found without exception, in the ligamentum nuchae of infected horses. The suspensory ligaments of the fetlock and flexor tendons were always negative.
3. The microfilariae of O. cervicalis concentrate along the...
Cursino AE, Vilela APP, Franco-Luiz APM, de Oliveira JG, Nogueira MF, Júnior JPA, de Aguiar DM, Kroon EG.Equine infectious anemia (EIA) has a worldwide distribution, and is widespread in Brazil. The Brazilian Pantanal presents with high prevalence comprising equine performance and indirectly the livestock industry, since the horses are used for cattle management. Although EIA is routinely diagnosed by the agar gel immunodiffusion test (AGID), this serological assay has some limitations, so PCR-based detection methods have the potential to overcome these limitations and act as complementary tests to those currently used. Considering the limited number of equine infectious anemia virus (EIAV) seque...
Ehizibolo DO, Gusi AM, Ehizibolo PO, Mbuk EU, Ocholi RA.Despite the endemicity of brucellosis in Nigeria, reports on equine brucellosis are rare. The Rose Bengal Plate Test (RBPT) was used to determine the serologic prevalence of Brucella abortus antibodies amongst 75 horses from three stables in two States of northern Nigeria. The highest prevalence (22.7%) was recorded in stable C located in Plateau State and the lowest (6.7%) was found in stable B in Kaduna State. The overall prevalence determined was 14.7%. There is need for the inclusion of horses in brucellosis surveillance and control strategies in Nigeria to safeguard people at high risk.
Costa LR, Johnson JR, Baur ME, Beadle RE.To describe the seasonal pattern of clinical exacerbation of summer pasture-associated recurrent airway obstruction (SPA-RAO) in relation to climate and aeroallergens in horses. Methods: 19 horses with SPA-RAO and 10 nonaffected horses. Methods: Daily examinations were performed on all horses while they were kept on pasture for 3 years. Onset and progression of clinical exacerbation based on a clinical score of respiratory effort were evaluated in relation to changes in maximum temperature, minimum temperature, mean temperature, maximum dew-point temperature, minimum dew-point temperature, and...
Ogbourne CP.Observations have been made on the development and survival of the free-living stages in faeces deposited out of doors at different times of year, and on the migration of infective larvae to the surrounding herbage. Laboratory experiments were performed to assist in the interpretation of the field observations. Studies were made on the rate of development to the infective stage in faeces kept at different temperatures. The rates at which eggs and larvae of Strongylus vulgaris, S edentatus, S. equinus and Trichonema nassatum developed on faecal-agar cultures at different temperatures were compa...
Halpin K, Graham K, Durr PA.Hendra virus (HeV) is a high consequence zoonotic pathogen found in Australia. The HeV vaccine was developed for use in horses and provides a One Health solution to the prevention of human disease. By protecting horses from infection, the vaccine indirectly protects humans as well, as horses are the only known source of infection for humans. The sub-unit-based vaccine, containing recombinant HeV soluble G (sG) glycoprotein, was released by Pfizer Animal Health (now Zoetis) for use in Australia at the end of 2012. The purpose of this study was to collate post-vaccination serum neutralising anti...
Boyle AG, Rankin SC, D○ L, Boston RC, Wheeler-Aceto H.Bacterial culture and polymerase chain reaction (PCR) assays for the detection of Streptococcus equi in nasopharyngeal washes (NPW) and guttural pouch lavage (GPL) samples have low sensitivity. In human diagnostics, processing of samples with flocked swabs has improved recovery rates of bacterial agents because of improved surface area and elution factors. Objective: For S. equi subsp. equi (S. equi) detection in NPW and GPL samples we hypothesized that: direct-PCR would be more reliable than flocked swab culture (FS culture); flocked swab PCR (FS-PCR) would be equivalent to direct-PCR; and FS...
Rogers CW, Firth EC, McIlwraith CW, Barneveld A, Goodship AE, Kawcak CE, Smith RK, van Weeren PR.No data exist on the intensity of exercise required or on possible harmful effects of increasing exercise in foals over the natural level when free at pasture. Objective: To investigate whether an increase in workload over free pasture exercise in the period from directly after birth to the start of training is tolerated by Thoroughbred (TB) foals without increasing injury rate or producing other undesired side effects. Methods: Thirty-three TB foals were allocated to one of 2 exercise groups directly after birth. One group (PASTEX) was raised on pasture and the other (CONDEX) kept under ident...
Zapf F, Schein E.The development of the piroplasm Babesia equi was studied by light microscopy in the gut and the haemolymph of three different Hyalomma species during and after the nymphs had engorged on parasitaemic horses. The stock of B. equi used was isolated from a horse imported from Turkmenistan (CIS) in 1991. The existence of gamogony was identified by the occurrence of gamonts and gametes in the gut contents of the nymphs at between 3 and 4 days after infestation of the nymphs, before the ticks dropped off the experimentally infected horses. Zygotes and kinetes were observed in the intestinal cells f...
Grinberg A, Learmonth J, Kwan E, Pomroy W, Lopez Villalobos N, Gibson I, Widmer G.Cryptosporidium isolates from diarrheic foals in New Zealand (n = 9) were identified as C. parvum, subtyped at two polymorphic loci, and compared with human (n = 45) and bovine (n = 8) isolates. Foal C. parvum isolates were genetically diverse, markedly similar to human and bovine isolates, and carried GP60 IIaA18G3R1 alleles, indicating a zoonotic potential.
Crouch CF, Daly J, Henley W, Hannant D, Wilkins J, Francis MJ.In horses, natural infection confers long lasting protective immunity characterised by mucosal IgA and humoral IgGa and IgGb responses. In order to investigate the potential of locally administered vaccine to induce a protective IgA response, responses generated by vaccination with an immunostimulating complex (ISCOM)-based vaccine for equine influenza (EQUIP F) containing A/eq/Newmarket/77 (H7N7), A/eq/Borlänge/91 (H3N8) and A/eq/Kentucky/98 (H3N8) using a systemic prime/mucosal boost strategy were studied. Seven ponies in the vaccine group received EQUIP F vaccine intranasally 6 weeks after...
Stover SM, Johnson BJ, Daft BM, Read DH, Anderson M, Barr BC, Kinde H, Moore J, Stoltz J, Ardans AA.Twenty-one horses had a complete unilateral humeral fracture during race training or racing at a California racetrack during the period 24 February 1990 to 10 July 1991. Fractures occurred approximately equally in left and right limbs, and in males and females. Most fractures occurred during training, and in 2- and 3-year-old horses. Only 5 of 16 Thoroughbred horses with known racing records had previously raced more than once, and their mean time between races was less than the time between their last race and fracture (P = 0.07). Ten of 13 humeri studied further had gross evidence of periost...
Lefrançois T, Blitvich BJ, Pradel J, Molia S, Vachiéry N, Pallavicini G, Marlenee NL, Zientara S, Petitclerc M, Martinez D.We conducted extensive surveillance for West Nile virus infection in equines and chickens in Guadeloupe in 2003-2004. We showed a high seroprevalence in equines in 2003 related to biome, followed by a major decrease in virus circulation in 2004. No human or equine cases were reported during the study.
Votion DM, Linden A, Delguste C, Amory H, Thiry E, Engels P, van Galen G, Navet R, Sluse F, Serteyn D, Saegerman C.Over the last decade, atypical myopathy (AM) in grazing horses has emerged in several European countries. An exploratory analysis was conducted to determine horse- and pasture-level indicators or factors associated with AM in Belgium. Belgian cases of AM confirmed by histology (n=57) were compared to their healthy co-grazing horses (n=77) and to pastured horses not involved with AM as controls (n=386). The pastures where confirmed cases were grazing (42 pastures; 38 sites; 44 incidences of AM) were compared with those of the controls (216 pastures; 96 sites; no incidence of AM). Statistically ...