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.
Misdorp W.A pathological study of 333 tumours of farm animals in the Netherlands is presented. Most of the tumours (224) were collected at the Amsterdam abattoir over a period of five consecutive years. The incidence of different types of the tumours is compared with figures compiled in the U.S.A. Tumours in cattle and pigs were less frequent in the Amsterdam material than in the U.S.A., but the incidence in horses and sheep was higher than reported elsewhere. Tumours of the jejunum, the ovaries and to a lesser extent of the heart were more frequent, but those of the skin and male genital organs were le...
Shortridge EH.Extract
Recent reviews of brucellosis in horses (Stableforth and Galloway, Citation1959; Mascaro and Hoffman, Citation1963: Ritscher, Citation1963) refer to Brucella abortus associated with fistulous withers, arthritis and debility and emphasize the rarity of abortion caused by this organism. One case of abortion in a mare caused by Br. abortus was reported as having occurred in Iowa, U.S.A. (McNutt and Murray, Citation1924).
Waller T, Rubarth S.The study comprises 49 dogs, 2 horses, and 2 cows with haemangioendothelioma, which have been subjected to autopsy over a period of 26 years. Most of the dogs were old, and there is an over-representation of male dogs. The results also indicate that the Alsation breed of dog is particularly susceptible to these tumours, as is the Boxer to some extent. The disease was in most cases of short duration and the most common clinical symptoms were sluggishness, fever, generalized anaemia, breathing difficulties, increased thirst, and leuco-cytosis. Most of the dogs fell ill and were subjected to auto...
Adam EN, Morley PS, Chmielewski KE, Carman J, Gonzales G.Because of the contagious nature of influenza virus it is necessary to identify infected individuals after the virus is introduced into a population. The aim of this study was to characterise influenza virus detection with commercially available assays after intranasal vaccinating horses with cold-adapted influenza virus. Seven horses were vaccinated and placed with 3 unvaccinated horses. Nasal secretion samples were evaluated using 2 antigen detection assays. All 10 horses were positive in the Flu OIA assay during the study period, but only one horse was positive on one sample using the Direc...
Wobbe M, Reinhardt F, Reents R, Tetens J, Stock KF.Awareness of breeders of Warmblood Fragile Foal Syndrome (WFFS) increased after a widely discussed case in the USA in 2018. The hereditary connective tissue disorder, first described by a US research group in 2011 and for which a commercial genetic test exists since 2013, is caused by a point mutation in the PLOD1 gene, inherited autosomal recessively. Extension of molecular genetic testing and reporting of test results of organized horse breeders to their studbooks implies new opportunities for analyses. In Germany, data are centrally accessible through the integrated equine data base allowin...
Horstmann T, Heitkamp HC, Mayer F, Hermann M, Küsswetter HW, Dickhuth H.The objective of this study was to compile knowledge of athletic injuries and complaint patterns related specifically to equestrian acrobatics (e.a.). A 20-page standardized questionnaire was sent to 114 e.a. participants. The mean age of the participants in e.a. groups was 15 +/- 3 years, that of independent participants 21 +/- 3 years. A total of 489 injuries was reported, mainly to muscles and tendons (35%), skin (33%) and joints and ligaments (25%). Bone injuries (6%) and head injuries (2%) were infrequent. Analysis of the localization showed that the head-face-neck region was involved in ...
Petry S, Breuil MF, Duquesne F.Contagious equine metritis (CEM) detection by PCR is recognized by the European Union according to Commission Implementing Regulation (EU) No 846/2014, and real-time PCR is now recommended by the World Organisation for Animal Health Terrestrial Manual at the same level as the culture method. The present study highlights the creation of an efficient network of approved laboratories in France in 2017 for CEM detection by real-time PCR. The network currently consists of 20 laboratories. A first proficiency test (PT) was organized by the national reference laboratory for CEM in 2017 to evaluate th...
Davis JG, Ragle CA, Hanna A, DeNome AT.To determine the location of the deep and superficial caudal epigastric arteries in relation to 3 midline positions and the relationship between the location of these arteries, body circumference, and body condition score. Methods: Descriptive anatomical study. Methods: Nine horses, aged 1-28 years (mean 10.61 ± 8.89 SD). Methods: Body condition score and body circumference were measured prior to euthanasia. Angiographic studies of the deep and superficial caudal epigastric arteries were performed on resected abdominal walls. The distances between the deep and the superficial caudal epiga...
Scholtz M, Guthrie AJ, Fosgate GT, Schulman ML.Population demographics and reproductive performance of Thoroughbred populations have been described, but the most recent assessment of the South African Thoroughbred population was reported two decades ago. Objectives of this study were to report demographic data for selected Thoroughbred breeding populations and to analyse selected mare-level variables in association with foaling outcomes, as predictors of reproductive performance. The National Horseracing Authority of Southern Africa's stud health scheme requires annual screening of Thoroughbred stallions, maiden and barren mares for venere...
Mir IA, Kumar B, Taku A, Bhardwaj RK, Bhat MA, Badroo GA.The present study was conducted to determine the prevalence of Rhodococcus equi infection in equines of Jammu and Kashmir, India, and evaluate the zoonotic threat posed by this organism to equine owners and tourists. One hundred and forty-one samples (98 samples from adult animals ≥5 years old and 43 samples from foals less than 6 months old) were collected in duplicate from nasopharyngeal tract of equines for isolation and direct PCR. A total of 12 isolates of R. equi were recovered, of which 9 were from foals and 3 from adult animals. Therefore, the present study recorded prevalence rates ...
Pusterla N, Mapes S, Leutenegger CM.A questionnaire was developed to document the knowledge base of large-animal diplomates of the American College of Veterinary Internal Medicine (ACVIM) regarding polymerase chain reaction (PCR) technology and to identify the common use of this technology in equine practice. Ninety-three of the 278 mailed questionnaires were returned, for an overall response rate of 33.4%. Ninety respondents (99%) reported being familiar with the general principles of nucleic acid probe technology; however, only 52 (57%) knew the difference between conventional (traditional) and real-time (second-generation) PC...
Duncan JL, Dargie JD.The migratory route of infective Strongylus vulgaris larvae was determined: penetration of small and large intestine into the lumina of submucosal arteries, migration up the arterial tree, reaching the cranial mesenteric site by three weeks, where the larvae develop to the mature 4th stage. After 3-4 months they exsheath and the young adults migrate down the arteries towards the intestines, to the limit of arterial narrowing, from where they rupture from nodules into the lumen of the intestine. The prepatent period is about 6 months. The clinical syndrome was similar to, but less severe than t...
Mavadiya SV, Raval SK, Mehta SA, Kanani AN, Vagh AA, Tank PH, Patel PR.A highly contagious virus infection in horses, influenza is the single most important equine respiratory disease in the world. This paper presents details of a one-year study (1 June 2008 to 31 May 2009) to determine the prevalence of equine influenza in the horses of Gujarat State in India. The prevalence of equine influenza A/equi-2 was 12.02%, but none of the samples were positive for equine influenza A/equi-1. The prevalence of equine influenza (A/equi-2) was 15.38%, 11.94%, 10.18%, and 9.09% in horses of the Kathiyawari breed, a non-descript breed, the Marwari breed and the Indian Thoroug...
Boorman S, Richardson DW, Hogan PM, Stefanovski D, Levine DG.To report the performance of thoroughbred racehorses after surgical repair of a medial condylar fracture of the third metacarpal/metatarsal bone. Methods: Retrospective cohort study. Methods: Forty-three horses surgically treated for medial condylar fractures, 30 with previous racing experience, 13 without previous racing experience (nonexperienced). Methods: Medical records (2009-2017) were reviewed for signalment, radiographic fracture characteristics, repair technique, and postoperative morbidity and mortality. Each experienced horse was matched with two horses randomly selected from its mo...
Finger MA, Biava JS, Dornbusch PT, Perotta JH, Ullmann LS, Serpa PBDS, Kmetiuk LB, Dos Santos AP, Biondo AW, Leutenegger C, Filho IRB.Molecular approaches to diagnose respiratory viruses have provided an opportunity for early and subclinical pathogen detection, particularly in samples from the upper respiratory tract. This study aimed to investigate the presence of herpesviruses, particularly equid herpesvirus (EHV)-2 and EHV-5, in samples from the lower respiratory tract of healthy racehorses from Southern Brazil. Unassigned: Samples from the lower respiratory tract (i.e., bronchoalveolar lavage fluid [BALF]) were assessed by video endoscopy, cytological evaluation of BALF, and tracheal aspirates (TA), along with quantitati...
Cogger N, Perkins N, Hodgson DR, Reid SW, Evans DL.To describe the impact of age, sex, and musculoskeletal (MS) injury on three preparation-level measures of performance: (i) the duration of preparation, (ii) time from the beginning of the preparation until the first start in a race or barrier trial, and (iii) time from the first start until the end of the preparation. Methods: Daily training and injury data for 2- and 3-year old Thoroughbred racehorses were collected fortnightly from 14 trainers in NSW, Australia. Training data were aggregated into units referred to as 'preparations'. Univariate and multivariate analytical methods were used t...
Martin GS, Strand E, Kearney MT.To determine the relationship between prediction errors of a regression model of racing finish times and earnings or finish position; the relationship between standardized finish times, determined by use of this model, and earnings or finish position; and whether this model was valid when applied to data for horses that underwent surgical treatment. Methods: Survey. Methods: Records of 6,700 healthy Thoroughbreds racing in Louisiana and of 31 Thoroughbreds with idiopathic left laryngeal hemiplegia that underwent surgical treatment. Methods: Predicted and standardized finish times were calculat...
Tryland M.In December 1801, the first vaccination against smallpox in Norway took place. Vaccine material came from Denmark, England, Ireland, and other countries; it was also obtained from a few local cowpox cases. What mattered was the effect, not the origin. Several reports indicate that variola virus itself, the cause of smallpox, was also used for human vaccination after passages through cows and horses. A vaccine institute for production of vaccine in calves was established in Kristiania in 1891. Cowpox was once a rare disease in cattle, but a total of 70,985 bovine cases were reported between 188...
Woods AC, Chesney AM.A filterable agent has been obtained from the humors and tissues of the eyes of horses suffering from active periodic ophthalmia. The intra-vitreous injection of this filtrate produced in normal horses the same clinical and pathological picture observed in the natural disease. This filtrate injected into rabbits produced a different clinical picture, but the essential pathological lesions closely resembled those found in horses. After passage of the filterable agent through six generations of rabbits, it again produced the clinical and pathological picture of the natural disease when injected ...
Klingeborn B.Twelve mares were vaccinated with attenuated equine abortion virus (EAV) strain RAC-H. Two nonvaccinated mares served as controls. In at least three mares the vaccination appeared to coincide with a natural infection. This was indicated by characterization of the EAV isolated from nasal secretions of six vaccinated mares, a nonvaccinated control, and also from the lung, spleen, and liver of a fetus aborted by a vaccinated mare. The relative sensitivity of the isolated EAV to dithiothreitol was used to distinguish the RAC-H strain and wild-type virus. Of the 10 EAV isolates, four were recognize...
Legrottaglie R, Agrimi P.Electrophoretic analysis in polyacrylamide gel (PAGE) of the equine rotavirus 106/88/LI/EQ, isolated from the diarrhea of an 18 day old foal was compared to the bovine strain NCDV. There was a notable difference in the migration of some segments of the viral RNA. Bands 2 and 3 of the equine rotavirus comigrated while there was a clear separation of segments 7, 8 and 9. Moreover, the migration of segments 1, 4 and 5 revealed a lower molecular weight than the corresponding segments of NCDV.
McLean NL, McGilchrist N, Nielsen BD.Racehorses are often supplemented extra iron with the expectation that the iron will improve overall performance and health. A survey of 120 U.S. Thoroughbred trainers, representing 1978 Thoroughbreds from various regions of the U.S., was conducted to determine the average amount of dietary iron fed to Thoroughbred racehorses per day. Survey results indicated racehorses were fed an average of 3900 mg of iron per day from hay and grain alone. This exceeds the 0.8 mg/kg BW or 400 mg for a 500 kg working horse that the NRC 2007 recommends per day. Supplements increased the daily average intake of...
Morris CM, Field HJ.Tissue specimens obtained from equine herpesvirus-1 (EHV-1), subtype 1-infected aborted foetuses were analysed for the presence of virus DNA by means of Southern blot and dot blot hybridisations. The specificity of the methods was confirmed although the sensitivity was inferior to classical techniques such as virus isolation. However, the possibility of detecting the state of the virus DNA and the ability to distinguish between subtypes were important features, and the dot blot method was shown to have potential for a rapid diagnostic test. This report demonstrates some potential practical app...
Morel MC, Newcombe JR, Reynolds N.The mare's reproductive system is rarely capable of sustaining multiple pregnancies to term. Multiple pregnancies largely derive from multiple ovulations, most commonly double ovulations, hence, double ovulations are of significant concern to breeders/veterinarians. Double ovulations may be synchronous or asynchronous. Asynchrony of up to 96 hours may result in two embryonic vesicles of very different sizes, which are challenging to detect at early ultrasonic pregnancy detection. This study aims to (1) document the incidence of synchronous and asynchronous double ovulation and (2) determine ...
Pozio E, Celano GV, Sacchi L, Pavia C, Rossi P, Tamburrini A, Corona S, La Rosa G.Epidemiological investigations conducted during 10 trichinellosis outbreaks between 1975 and 1994 showed that horse-meat was the probable source of infection. Though hundreds of thousands of horses have been examined at abattoirs in America and Europe to detect Trichinella infection by artificial digestion or trichinelloscopy, an infected horse has never been detected during routine analysis, which consists of examining 1 g of tissue muscle from the diaphragm. In November 1996, a naturally infected horse imported from Romania was detected in Southern Italy. The parasite was identified as Trich...
Paweska JT, Henton MM, van der Lugt JJ.Clinical, virological and serological responses were evaluated in 10 pregnant mares after different challenge exposures to the asinine-94 strain of equine arteritis virus (EAV). The outcome of maternal infection on the progeny was also investigated. Mares were inoculated intranasally (n = 4), intramuscularly (n = 2), intravenously (n = 1), or contract-exposed (n = 3). All inoculated mares developed pyrexia, 5 showed mild clinical signs related to EAV infection and 2 remained asymptomatic. Viraemia was detected in all the inoculated animals and shedding of virus from the respiratory tract occur...
Lord CC, Woolhouse ME, Mellor PS.Factors affecting epidemics of African horse sickness in Spain were studied using a mathematical model. The model examined the likelihood of an epidemic after the introduction of the virus, and the effectiveness of vaccination strategies. Two host species (horses and donkeys) and one vector species (the biting midge Culicoides imicola) were included. A stratified random sampling method (Latin hypercube sampling) was used for sensitivity analysis of the likelihood of an epidemic. Systematic variation of vaccination parameters was used to consider alternative control strategies. In general, when...
Page AE, Stills HF, Horohov DW.Multiple hypotheses into the age-based susceptibility of animals to Lawsonia intracellularis exist, including the decline of passively acquired antibodies. Objective: To determine whether the decline in passively acquired antibodies in horses is responsible for the age predilection of equine proliferative enteropathy (EPE). Additional objectives included examination of various risk factors for the development of EPE as well as the determination of naturally occurring attack rates for clinical and subclinical EPE. Methods: Prospective, multifarm field study. Methods: A total of 369 mare and f...
Kaneene JB, Miller R, Ross W, Gilbert L.Data from two 12 month prospective monitoring programs that followed management, economics and animal health from randomly-sampled equine operations in Michigan were used to determine patterns of health maintenance. Health maintenance measures were grouped, and average uses per year were computed for the most-common measures reported: respiratory, Potomac Horse Fever, neurological and multiple-system vaccinations, deworming, and general farrier work. Factors examined for potential association with health maintenance measure use were numbers of equids and horse-days on the operation, average ag...
Büchi S, Waelchli RO, Corboz L, Gygax AP, Wälti RJ.In the mare, natural breeding is associated with bacterial contamination of the reproductive tract. The purpose of this study was to examine postcoital bacterial contamination and the resulting inflammatory response of the uterus. Uterine swabs for bacteriological and cytological examination were obtained from 80 mares. Each mare was sampled once between 4 and 69 hours postbreeding. In mares which did not conceive, sampling was repeated at the following estrus. The findings were compared with those obtained prior to breeding and correlated with the breeding outcome. Bacteria were cultured from...
Carrier SP, Boulanger P, Bannister GL.The comparative values of the direct, the indirect complement-fixation and the agar-gel immunodiffusion tests were assessed for the diagnosis of equine infectious anemia. Antibodies were detected on the agar-gel immunodiffusion test as early as 18 days post-inoculation in the serums of experimentally infected horses and were readily detectable in all the subsequent bleedings. Complement-fixing antibodies, demonstrable by the direct method, were detected commencing about the same time. However, these were not long-lasting and were replaced by the non-complement-fixing antibodies demonstrable by...
Page AE, Stills HF, Chander Y, Gebhart CJ, Horohov DW.Lawsonia intracellularis is the causative agent of equine proliferative enteropathy (EPE), a disease for which no large-scale seroprevalence studies have been conducted. Objective: To validate and use an equine-specific enzyme-linked immunosorbent assay (ELISA) for L. intracellularis to determine the seroprevalence of L. intracellularis on numerous farms. Methods: An ELISA, in which purified antigen was used, was adapted from previous work in swine. A total of 337 Thoroughbreds from 25 central Kentucky farms were enrolled and monthly serum samples collected from August 2010 to January/February...
Johns I, McParland T, Mair T.Pleural effusion (PE) is reported to occur most commonly secondary to bacterial pneumonia or lung abscesses, with neoplastic effusions contributing the minority of cases. The majority of these reports originate from America and Australia, where long distance transport of horses, a recognised risk factor, appears to occur more frequently. Anecdotally, neoplastic PE is more commonly diagnosed in the UK. Objective: To describe the causes of PE in horses resident in the UK, and to identify potential markers that can help differentiate between infectious and neoplastic causes of PE. Methods: Retros...
