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.
Jones RH, Hayes RO, Potter HW, Francy DB.A survey of biting flies in the southwestern United States resulted in the recovery of 34 species as they attacked equines. The geographic distribution of each species at 15 sites and the abundance of attacking flies were used to determine that 22 species commonly attack equines. Culicoides variipennis (Coquillett) was the most common species collected; it was recovered at 12 sites and comprised the highest percentage (29.8%) of the total survey catch for all species collected. The next 2 most common species were Psorophora columbiae (Dyar & Knab) and Aedes vexans (Meigen). C. variipennis was ...
O'Driscoll JG, Troy PT, Geoghegan FJ.The clinical pattern, bacteriological investigation and subsequent treatment of a serious outbreak of venereal disease in stud farms on both sides of the Irish Sea is described. The consistency with which Bacillus proteus was isolated from infected mares and stallions was remarkable. Prompt treatment with ampicillin, to which the organism was sensitive in vitro, eradicated the disease. No local treatment was applied.
Goto H, Shimizu K.The first outbreak of equine influenza (EI) infection in Japan was recognized during the period December 1971 to January 1972 [1, 6]. No evidence of the disease had been found before then [2,6]. The etiological agent of this epizootic was identified by hemagglutination-inhibition (HI) and neutralization tests with chicken or ferret antiserum as the subtype 2 of EI virus (6, 7). However, the isolate, A/equine/Tokyo/71 (Tokyo) strain, was not completely identical to the prototypic A/equine/Miami /63 (Miami) strain of the subtype 2, since antibody responses of convalescent horses were 2 to 16 tim...
McQueary CA, Worley DE, Catlin JE.Of 22 foals from 4 localities in southwestern Montana, 59% were found to be infected with Eimeria leuckarti. Oocysts collected from feces of 4 positive horses were sporulated and subsequently administered to a 5- to 6-month-old foal. The prepatent period was 31 days and the patent period was between 5 and 10 days.
Grelck H, Hörchner F, Wöhrl H.Ten pony foals were infected with Fasciola hepatica; five animals received up to 1000 metacercariae orally, the remaining animals received up to 80 specimens of 24 hours old adulescariae intraperitoneally. The rate of development of the parasites varied in a wide range between 0,2 and 41%. Most of the liverflukes were found in animals severely infected with strongyles in the same time. Only 22 weeks after oral infection, the flukes had reached a length of 20 mm and sexual maturity. Fasciola-eggs could not be detected in the feces.
Dutta SK, Campbell DL.Blastic transformation of peripheral blood mononuclear cells and serum neutralization antibody levels for equine herpesivurs type 1 were measured in 19 mares from three farms at the time of termination of their pregnancy by normal foaling or viral abortion. The stimulation indexes of lymphocytes obtained from the mares from two farms (Farm 1 and 2) which had virus abortions, ranged from 2.1 to 10.8. But there was no significant difference in stimulation index levels between the aborting and normal foaling mares on these two farms. Equine herpesvirus type 1 was isolated from the mononuclear cel...
Jahrling PB, Beall JL.Hydroxylapatite column chromatography methods were developed to characterize selected alphavirus populations. Different conditions of pH and phosphate molarity were required to obtain satisfactory elution profiles and separations for Western equine encephalomyelitis virus strains, compared with Eastern equine encephalomyelitis virus and Semliki Forest virus strains. Raising the pH of the buffers effected earlier elutions of all viruses. Selection of phosphate gradients with more gentle slopes and adjustment to the proper pH effected better separations of virus subpopulations. Elution profiles ...
Knight HD, Costner GC.During the summer and fall of 1973, a few horses, goats, and cattle in the Napa Valley of California became intoxicated by bromide via the ingestion of volunteer oat hay that had been cut from a field treated with methyl bromide, a soil fumigant. The bromide content of the hay ranged from 6,00 to 8,400 ppm. Signs of intoxication were lethargy, weakness, and ataxia. Animals experimentally fed the contaminated hay developed signs of intoxication between the 7th and 9th days.
Verma BB, Biberstein EL, Meyer ME.A serologic survey was made of the prevalence of common leptospiral infections in horses in California. A total of 465 serums were tested, using the microscopic agglutination method, against 5 leptospiral serotypes: Leptospira pomona, Leptospira icterohaemorrhagiae, Leptospira canicola, Leptospira grippotyphosa, and Leptospira hardjo. Of the serums tested, 127 (27.30%) were positive against 1 or more of the leptospires, with percentage distribution among the reactors as follows: L pomona, 12.47%; L icterohaemorrhagiae, 10.32%; L canicola, 3.22%; L grippotyphosa, 0.86%; and L hardjo, 0.43%. The...
Leegaard J, Roth A.Case history, skin tests and RAST were compared in a group (n = 40) of children with a history suggesting allergy to horses and in a group (n = 43) in whom there was no suspicion of hypersensitivity to horses. There was an agreement of 91% between case history and prick test. The same magnitude of agreement was found between case history and RAST (89%), and the agreement between RAST and prick test was 90%. The results of this investigation are clearly in contrast to earlier earlier reports, in that there was a very good correlation between prick test, RAST and case history. The results sugges...
Shen DT, Crawford TB, Gorham JR, McGuire TC.Twelve chemicals and commercial disinfectants were tested for inactivation of equine infectious anemia virus. In the presence of 10% bovine serum, all chemicals inactivated 4 log10 (based on 0.1 ml) of the virus within 5 minutes at 23 C. A reduction of at least 4 log10 was observed when the virus was exposed for 1 minute to substituted phenolic disinfectants (3 commercial preparations and sodium orthophenylphenate), halogen derivatives (iodophor and sodium hypochlorite), chlorhexidine, and 70% ethanol. Sodium hydroxide (5%), 2% formalin, and 2% glutaraldehyde were slower to inactivate the viru...
Kucera CJ, Beckenhauer WH.An inactivated, aluminum hydroxide adjuvant equine influenza vaccine was tested in horses and guinea pigs to determine the levels of antigen that would elicit maximum serological responses. Vaccine containing serial twofold increments of A/Equi-1/Prague and A/Equi-2/Miami strains of equine influenza virus was administered to random groupings of both types of test animals. The hemagglutination inhibition antibody response for each group was then measured. Results in horses and guinea pigs were compared to determine if the equine serological values could be related to a potency test in laborator...
Rushton JO, Tichy A, Kolodziejek J, Nowotny N, Nell B.The prevalence of linear keratopathy with progressing age in a closed population of a single horse breed is reported. All Lipizzaners in three federal states in Austria underwent complete ophthalmic examination four times over a period of 18 months, with six-month intervals. Findings consistent with linear keratopathy were recorded, and associated with factors such as sex, location, boarding system and level of performance throughout the study period. Logistic regression was applied to determine the influence of age on ophthalmic findings. On the first, second, third and fourth examinations, 0...
Smiet E.Lately there has been a tendency to discuss Equine Cushing's disease and its related phenomena, due to the amount of recently acquired research data. The author has composed a brief overview of the present situation emphasizing relevance for practitioners.
Millar R, Francis J.Day (1939) recorded 95% fertility in wild
ponies, but in heavy horses it was only 52%
and in thoroughbreds 68%. Variation of fertility was stated by Anderson (1922) was not due
to disease or physiological malfunction, but to
highly artificial methods of mating. In New
Zealand, Bain (1948) recorded the fertility of
mares in 1944 as 61%. MahaiIey (1950) made
a survey in Western Australia and found fertility
rates which varied from 17% to 50% before
veterinary assistance was obtained.
An article in the British Racehorse (Anon
1949) revealed no evidence of any progress in
the control o...
Belonje PC, van Niekerk CH.Attention is drawn to the beneficial effect of improved nutrition during winter and early spring on the ovarian activity of mares. Furthermore, the necessity of an adequate plane of nutrition during early pregnancy to prevent embryonic resorption is stressed.
Mele M, Ramseyer A, Burger D, Brehm W, Rieder S, Marti E, Straub R, Gerber V.Many of the important diseases of sport and pleasure horses are thought to have a genetic component. The majority of these diseases, however, are multifactorial and are influenced not only by genetics, but also by environmental factors. In this review some of the most important multifactorial diseases are described and the current evidence for a genetic background is discussed.
Zurkowski M, Kuryl J.A new genetic variant in the horse Pi system, designated Z2, was reported in Polish Arabs by using two-dimensional agarose polyacrylamide gel electrophoresis. The frequencies of Pi alleles F, G, L, L2, N, S, U, W, Z and Z2 were found to be 0.036, 0.005, 0.171, 0.013, 0.008, 0.237, 0.416, 0.003, 0.107 and 0.004 respectively.
Rogger P, Herrmann N, Ottiger H.The registration of adverse events after the use of immunological veterinary medicinal products (VMP) is the aim of the vaccinovigilance reporting system in Switzerland. Adverse events comprise suspected adverse reactions and lack of expected efficacy. Since the Institute of virology and immunology (IVI) is the competent authority for the regulation of immunological VMP in Switzerland, the reporting system is administrated by the IVI. In 2018, 162 reports concerning authorized immunological VMP were received. While most of the reports were submitted by the marketing authorization holders (79%)...