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.
Leach DH, Crawford WH.This paper describes the major areas that require investigation in equine locomotion and outlines a plan for such research in both the Thoroughbred and Standardbred. Fifteen topics for future investigation have been selected and given an order of priority. These topics deal with characteristics of normal locomotion, factors which influence locomotion, the epidemiology and economics of lameness and the clinical identification of lameness.
Revington M.Eight hundred and sixteen blood samples were collected from horses at Sydney race tracks, 1 to 3 h before racing, and subjected to haematological analysis. Haemograms were also performed on 65 blood samples taken from horses at rest in their stalls. These were used as reference values of prerace and resting haemograms, respectively. The haemograms of 29 of the resting horses were compared with the haemograms of the same 29 horses the following day at the race track. Both samples were considered to be representative of their reference populations. In general, there was a significant increase fr...
Ribbeck R, Heide H, Schicht W, Hiepe T.Observations were carried out from May 1977 to May 1980 on occurrence, fauna, and seasonal dynamics of Gasterophilus spp. in 2,539 horses for butchering from all districts of the German Democratic Republic and also in 79 horses after control against gasterophilosis. 99.98% of the 13,742 second and third instar larvae of horses for butchering were Gasterophilus intestinalis, only 0.02% Gasterophilus nasalis. Out of 7,765 larvae passed after control measures Gasterophilus intestinalis dominated with more than 96%. Only in four districts of the German Democratic Republic Gasterophilus nasalis was...
Wiebe ME, Scherer WF, Peick WJ.Ninety-four strains of Venezuelan encephalitis (VE) virus isolated from sentinel hamsters exposed in the Middle American countries of Mexico, Guatemala, Belize, and Honduras were examined for the presence of virions with marker characteristics of strains that cause large epidemics and equine epizootics. Thirty-four strains came from before and 60 strains came from after the Middle American epidemics and equine epizootics of 1966 and 1969-1972. Twenty-three virion clones that resembled epizootic strains by hydroxylapatite chromatography and Vero monkey kidney cell plaque size determinations wer...
Miller RI.Although 'phycomycosis' is a common disease of horses in northern Australia little is known about the causative fungi. In this paper the laboratory methods for diagnosis are described. These revealed 38 cases caused by Pythium sp. (Hyphomyces destruens), 6 cases caused by Basidiobolus haptosporus and 2 caused by Conidiobolus coronatus. Laboratory studies on the chemotatic behaviour of zoospores of Pythium sp. showed that they were strongly attracted to both animal hairs and plant tissue. Because of this behaviour a simple baiting method using human hair was used to trap the fungus from water s...
Bailey E.336 Standardbred mares and 334 Thoroughbred mares in the vicinity of Lexington, Kentucky, were lymphocyte typed for 11 allelic antigenic specificities of the equine lymphocyte antigen (ELA) system. The Standardbred mares were divided into a population of pacers and a population of trotters. Substantial differences in ELA gene frequencies were found between the 3 groups. When the distribution of antigens within populations were compared to Hardy-Weinberg equilibrium expectations, relatively good agreement was found.
Nakazawa M, Sugimoto C, Isayama Y.The selective isolation of R. equi in NANC medium was made by quantitative culture of the organism in the feces. R. equi was observed in the feces of all the mares and foals investigated. The mean viable count of R. equi organisms in 1 gram of feces was 8.42 X 10(2) in the mares and 7.57 X 10(2) in the foals, and its 95% confidence limits were in a range of 6.48 X 10(2) to 1.09 X 10(3) and 4.19 X 10(2) to 1.37 X 10(3), respectively. This result indicates that R. equi is a member of the normal intestinal flora in the horse.
Dutta SK, Myrup AC.A novel, simple method of infectious center assay was developed to detect and quantitate the intracellular existence of equine herpesvirus 1 and equine herpesvirus 2 in peripheral blood mononuclear cells infected in vivo and in vitro with the viruses by cocultivation of these cells with a permissive equine cell culture. The infectious center titers were correlated with the infectious virus titers. In vivo equine herpesvirus 1-infected mononuclear cells obtained from ponies experimentally infected with the virus and equine herpesvirus 2-infected mononuclear cells obtained from selected naturall...
Matuschka FR.The dog is the final host for sarcosporidia cysts from the oesophagus and diaphragm of donkeys from Sardinia. The prepatent period lasted 9 to 10 days. Sporocysts measured 12.2-13.8 X 9.2-9.9 microns. Infection of a horse with 10(5) donkey/dog sporocysts increased the rectal temperature to more than 40 degrees C on days 10 and 20 after infection. On day 138 p.i. predominantly immature cysts containing metrocytes were found, especially in the oesophagus. Infection on day 117 p.i. with 2 X 10(5) horse/dog sporocysts did not give rise to a temperature increase during the following 21 days. The fi...
Bernhang AM, Winslett G.In brief: It has always been assumed that participants in equestrian sports are at high risk of serious injury and that minor injuries are common. This study of American Horse Shows Association and United States Pony Clubs horse shows tried to determine if shows are as safe as or safer than other sports, what the accident rate is for horse shows, if any factors influence the accident rate, and what types of accidents and injuries occur. There were 290 reported injuries and two deaths in the 984 responding shows. The accident rate per entry was 0.0003. There was no statistically significant rel...
Hinshaw VS, Naeve CW, Webster RG, Douglas A, Skehel JJ, Bryans J.Influenza outbreaks involving viruses of the H3N8 subtype (equine 2) often occur in vaccinated horses. For this reason, a series of influenza viruses of the H3N8 subtype were examined to determine if antigenic variation could be detected in isolates during the period 1963-81. Antigenic analyses with post-infection ferret sera and monoclonal antibodies showed that the haemagglutinins of recent isolates were antigenically distinguishable from the prototype A/eq/Miami/1/63 and that antigenically distinguishable groups of equine 2 viruses co-circulate in the horse population. Based on these studie...
Studdert MJ.DNA was prepared from 43 equine herpesvirus type 1 (EHV 1) isolates, 11 of which were from horses with respiratory disease, 22 from aborted equine foetuses, and 10 from foals that died perinatally. The restriction endonuclease DNA fingerprints of 10 of the 11 respiratory isolates, known with certainty to have been recovered from horses with respiratory disease, were entirely different from all but 3 of the 32 foetal or perinatal foal isolates. The exceptional respiratory isolate, EHV 1 Army 183, had a foetal (F) strain fingerprint but this virus cannot be said with certainty to have been isola...
Ostlund C, Pero RW, Olsson B.1. The reproducibility of blood pressure determinations on 103 male horses gave an average coefficient of variation of 5.0%. 2. Different parameters affecting the methodology of blood pressure measurements were separately analysed; i.e. size of specimen, size of cuff in relationship to tail circumference and temperature of the environment. 3. A strong positive linear correlation between age and blood pressure in the horse was established for two breeds with widely varying genetic background--Swedish Warmbloods and Arabians.
Foster NM, Barber TL, Walton TE.Venezuelan equine encephalomyelitis (VEE) TC-84 vaccinal virus, from 10-1. quantities of infected duck embryo fibroblast cell culture fluids, was isolated by combined continuous-flow centrifugation with isopycnic banding in sucrose. Most of the recovered infectivity and hemagglutinating activity were in a single band at a buoyant density (rho) of 1.2. About 90% of the total input protein (450-520 mg) was removed with the effluent, whereas most of the remaining 10% also banded at a rho of 1.2. Infectivity was inactivated with formalin at a final concentration of 0.05% at 37 degrees C for 24 hr....
Ryder E, Ryder S.Venezuelan equine encephalitis (VEE) virus has been implicated as producing alterations in glucose metabolism in animals. We performed oral glucose tolerance tests and measured serum immunoreactive insulin responses in 13 patients who were infected by VEE virus during an epidemic in 1969, in Zulia State, Venezuela. No significant alterations in the glucose tolerance test were found. Sera of 86 diabetic outpatients and 98 control individuals with normal glycemia at a local hospital were tested for antibodies to VEE virus by hemagglutination inhibition. No statistically significant difference wa...
Cloonan MJ, O'Neill BJ, Vale TG, Carter IW, Williams JE.The sera of 468 blood donors and 63 domestic animals, collected from the south coast of New South Wales, were tested for the presence of antibodies to Ross River virus. Antibodies were detected in 7% of human sera, 25% of cow sera and 65% of horse sera. Using the blood donors as 'human sentinels', seroconversions were demonstrated in two donors from the Nowra-Kiama region and from a patient in the same area; none of the three had been outside of the study area during the period of seroconversion or at the time of infection. Of the 15 seropositive horses, 6 (40%) had lived continuously since bi...
Craig TM, Courtney CH.The kind of parasites a horse acquires depends upon its environment. Because patterns of transmission vary greatly with climate and management, no one worming program has universal applications. This article discusses epidemiology and control of equine parasites in the southern United States, where climates vary from warm temperate to subtropical and from humid in the southeast to arid in the southwest.
Balasuriya UB.The primary goals of this chapter are to discuss common viral RNA isolation and purification methods that are routinely used by various diagnostic laboratories, to highlight the advantages and drawbacks of each method, and to identify the most suitable and reliable method to increase the sensitivity and specificity of RT-PCR assays for the detection of equine influenza virus (EIV) in clinical specimens. Our experiences and review of literature show that magnetic bead-based nucleic extraction methods (manual and automatic) work well for isolation and purification of EIV RNA from nasal swab spec...
Hemida MG, Alhammadi M, Daleb A, Alnaeem A.African horse sickness virus (AHSV) is one of the most devastating viral diseases of the family Equidae. Infection with AHSV threatens not only the Saudi equine industry but also the equine industry worldwide. This is due to the high morbidity and mortality rates among the infected population of up to 100%. The World Organisation for Animal Health (OIE) lists AHSV among its notifiable diseases; this requires Member Countries to monitor the situation with regard to AHSV very carefully in order to avoid the spread of the virus. The OIE also suggests the systematic monitoring of AHSV in the equin...