Equine encephalosis in Thoroughbred foals on a South African stud farm.
Abstract: Thoroughbred foal body temperature data were collected from shortly after birth until shortly after weaning during the 2007/2008 season on a stud farm in the Western Cape Province of South Africa. Equine encephalosis (EE) caused by EE virus (EEV) serotype 4 (EEV-4) occurred in the foal group during the first autumn after their birth (March and April 2008). A descriptive study was undertaken to provide data on the EEV maternal antibody status, the association between pyrexia and EEV infection, and the incidence of infection amongst the foals prior to and during the episode. This included the frequent capturing of foal body temperature data and regular collection of serum and whole blood during pyretic episodes. Infection by EEV was determined using both virological and serological methods. A high EE incidence of at least 94% occurred amongst the foal cohort, despite the fact that 37% of foals had previously shown maternal antibody to EEV-4. Pyrexia in foals was not directly associated with EE infection and 41% of infected foals showed no detectable pyretic episode. Information obtained from this EE episode showed the high incidence of EEV infection in foals during the first autumn after their birth. Monitoring foal body temperature can alert farmers to outbreaks of infectious disease, such as EE. These results are relevant to the epidemiology of EE and facilitate greater understanding of it as a differential diagnosis of African horse sickness (AHS), given that EE and AHS have similar epidemiologic profiles.
Publication Date: 2015-09-30 PubMed ID: 26842364PubMed Central: PMC6238798DOI: 10.4102/ojvr.v82i1.966Google Scholar: Lookup
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- Journal Article
- Research Support
- Non-U.S. Gov't
Summary
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This study describes an incidence of equine encephalosis (EE), a horse disease, in Thoroughbred foals on a stud farm in South Africa. The findings suggest a high EE virus infection rate among foals, irrespective of maternal antibody status, with many unaccompanied by fever, and emphasize the need to consider EE as a differential diagnosis for African horse sickness.
Objective of Research
- The aim of this descriptive study was to gather data related to Equine encephalosis virus (EEV) humanitarian antibody status, the relationship between EEV infection and pyrexia (fever), and the frequency of infection among the foals before and amid the EE episode.
Methodology
- The researchers studied Thoroughbred foal body temperature data collected from shortly after birth until shortly after weaning during the 2007/2008 season.
- An episode of EE caused by EEV serotype 4 (EEV-4) occurred in the foal cohort during the first autumn after their birth.
- Data on foal body temperature was captured frequently, and serum and whole blood were collected periodically during pyretic episodes.
- The infection by EEV was determined using virological and serological methods.
Results
- Despite 37% of foals having shown prior maternal antibody to EEV-4, the EE incidence was at least 94% amongst the foal cohort.
- There was no direct association found between EE infection and Pyrexia in foals as 41% of infected foals exhibited no detectable pyretic episode.
Significance of the Research
- This study emphasises the high prevalence of EEV infection in foals during the first autumn after their birth.
- Monitoring the body temperature of foals would help in alerting farmers to potential disease outbreaks like EE.
- The results of this study are of importance to the epidemiology of EE as they aid in a comprehensive understanding of the disease as a differential diagnosis of African horse sickness (AHS) – a disease with similar epidemiological profiles.
Cite This Article
APA
Grewar JD, Thompson PN, Lourens CW, Guthrie AJ.
(2015).
Equine encephalosis in Thoroughbred foals on a South African stud farm.
Onderstepoort J Vet Res, 82(1), 966.
https://doi.org/10.4102/ojvr.v82i1.966 Publication
Researcher Affiliations
- Western Cape Department of Agriculture: Veterinary Services, Elsenburg, South Africa; Department of Production Animal Studies, University of Pretoria, South Africa. johng@elsenburg.com.
MeSH Terms
- Animals
- Antibodies, Viral / analysis
- Enzyme-Linked Immunosorbent Assay / veterinary
- Fever / epidemiology
- Fever / veterinary
- Fever / virology
- Horse Diseases / epidemiology
- Horse Diseases / virology
- Horses
- Incidence
- Orbivirus / isolation & purification
- Prevalence
- Reoviridae Infections / epidemiology
- Reoviridae Infections / veterinary
- Reoviridae Infections / virology
- Seroepidemiologic Studies
- South Africa / epidemiology
Conflict of Interest Statement
The authors declare that they have no financial or personal relationships which may have inappropriately influenced them in writing this article.
References
This article includes 14 references
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