Topic:Epidemiology
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.
Neutropenia and salmonellosis in hospitalized horses. Colitis due to salmonellae was diagnosed in 9 horses following hospitalization for various reasons at the University of Missouri Veterinary Teaching Hospital, from May, 1971, to April, 1972. Diarrhea, fever, and either a neutrophil count of less than or equal to 3,600/cmm or a rapid decline in neutrophil numbers were specific for salmonellosis. The value of hematologic survelillance in hospitalized Equidae was demonstrated in another group of 9 horses with neutropenia, each of which was promptly treated and did not develop colitis. Bacteriologic culturing of fecal samples from 28 clinically no...
Epidemiology of equine streptococci. Equine tonsillar tissue and the draining regional lymph nodes, as well as deep nasal swabs were examined bacteriologically. Group C streptococci, predominantly Streptococcus zooepidemicus, were shown to be present in all tissues. The most frequent site for isolation was the tonsil. Streptococcus equi was not located in any of the tissues sampled.
Studies on the dynamics of Strongyloides egg release under stud conditions. The eggs of Strongyloides westeri were found in the faeces of the foals from the 16th day of their life, with a peak in their numbers between the 30th and 40th day of life. Egg release ceased in all foals irrespective of their date of birth in the months July-August. Parallel examinations of the mares were negative. Recommendations for the control of strongyloidosis in foals are given.
The growth of African horse-sickness virus in embryonated hen eggs and the transmission of virus by Culicoides variipennis Coquillett (Diptera, Ceratopogonidae). Seven-day-old embryonated hen eggs were infected with African Horse Sickness virus by the yolk sac and intravenous routes. Virus reached a high titre in the blood of infected embryos. Culicoides variipennis midges which took a blood meal from infected eggs became infected with virus, and after 7 days at 26 degrees - 27 degrees C transmitted African Horse Sickness virus to uninfected eggs. C. variipennis may therefore be considered a biological vector of African Horse Sickness virus in the laboratory.
Epidemic Venezuelan equine encephalitis in North America in 1971: vector studies. A major epidemic of Venezuelan equine encephalitis occurred in south Texas in the summer of 1971. More than 1500 equines died of VEE in Texas, and 110 human cases with no deaths were reported. Vector studies in south Texas and northern Tamaulipas revealed that the overall mosquito infection rates during the peak of the epidemic were about 1:100, one of the highest rates observed for a major epidemic. Mosquito infection rates of this magnitude could easily explain the intensity of VEE outbreaks in both equines and man. A total of 943 VEE virus isolations were made from mosquitoes. Eight of the ...
Arbovirus vector ecology studies in Mexico during the 1972 Venezuelan equine encephalitis outbreak. Virus vector studies were conducted in the States of Durango, Chihuahua, and Tamaulipas, Mexico, in June and July 1972. Apparently only a low level of Venzuelan equine encephalitis (VEE) virus transmission to equines occured at the time of the study, and the infection was restricted to areas which had not experienced overt activity during the preceding year. The low level of infection was associated with a scarcity of mosquitoes. The IB (epidemic) strain of VEE virus was isolated from two pools of Anopheles pseudopunctipennis (Theo.) and the blood of one symptomatic equine. The low mosquito po...
Epidemic Venezuelan equine encephalitis in North America in 1971: vertebrate field studies. Epidemic Venezuelan equine encephalitis in North America in 1971: vertebrate field studies. Am J Epidemiol 101:36-50, 1975.-In June 1971, epidemic Venezuelan equine encephalitis (VEE) invaded the lower Rio Grande Valley in south Texas. The Boca Chica area of Cameron County was selected as a study site to investigate vertebrate involvement in the natural cycle of epidemic VEE on the basis of considerable evidence of VEE virus activity there in equines, humans, and mosquito vectors. Only one VEE virus isolation was made from 4739 wild and domestic non-equine vertebrates, although numerous equine...
Castration and other factors affecting the risk of equine laminitis. The characteristics of a series of equine laminitis cases were compared with that of other Equidae examined at the University of Missouri Veterinary Hospital and Clinic during May, 1965 through December, 1971. The model age for ponies with laminitis was 7-9 years and for all other cases the model age was 4-6 years. Also the predominant age for mares was 4-6 years and for males was 7-9 years. After controlling for age and breed differences, there were significantly fewer castrated males among the affected males than expected (P small than 0.02), indicating that hormonal factors may play a role ...
[Contribution to the antigenic study of influenza viruses in animals. II.–Antibodies, antineuraminidase in horse: conditions of apparition and importance (author’s transl)]. In the first part of this paper the conditions for a specific titration of antibodies against the neuraminidase (N) of each of the two horse virus subtypes are defined. The antigens used are: the H72Neq 1 recombining agent to measure the anti Neq1 antibodies and the A/Duck/Ukraine/63 strain for the anti Neq2 antibodies. The immunity response to neuraminidase appears after the natural disease; this response is studied in two foci, one due to a virus belonging to the A equi I subtype (Loire 73 strain), the other to a virus of the A equi 2 subtype (SHN 73 strain). The kinetics of apparition of an...