Prevalence of and risk factors associated with Salmonella shedding among equids presented to a veterinary teaching hospital for colic (2013-2018).
- Journal Article
Summary
The research article is a retrospective study that aimed to identify the prevalence of and risk factors associated with equids, particularly horses, shedding Salmonella while experiencing colic. The study revealed a lower prevalence rate compared to previous studies and identified certain clinical signs that could be useful in early detection of Salmonella shedding.
Objectives
The purpose of the study was to determine:
- The prevalence of Salmonella shedding amongst horses who experience colic
- What risk factors are associated with Salmonella shedding in these horses
Methods
The study used a retrospective case-control design wherein, for each colic case that tested positive for Salmonella, two that were negative were used as controls.
- Out of the 1917 horses that presented with colic, 1585 were tested for Salmonella
- 56 of the tested horses came out positive for Salmonella
- Statistical methods, namely logistic regression, were used to identify associations between various variables and Salmonella shedding
- Two types of models were used: one using clinicopathological data collected when the horse was presented, and the other using clinical variables that developed over the course of the horses’ hospitalisation
Results
The prevalence of Salmonella shedding was found to be 3.5%. The study identified several risk factors associated with Salmonella shedding such as:
- Horses being more likely to shed Salmonella in July
- Presence of fever and increased lactate levels
- Neutropenia or decreased levels of neutrophils, a type of white blood cell
In addition, horses shedding Salmonella were more likely to have a fever or develop reflux.
Limitations
The limitations of the study included the retrospective nature of the study, potential bias in retrieving data from medical records, and the possibility of misclassification of Salmonella status because it was based on a single sample.
Conclusion
Despite a lower prevalence rate compared to previous studies, the research found that certain clinical signs such as fever or the development of reflux were associated with Salmonella shedding. This could potentially assist clinicians in promptly identifying horses that are likely to shed the bacteria, thereby helping institute effective nursing precautions.
Cite This Article
Publication
Researcher Affiliations
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California-Davis, Davis, California, USA.
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California-Davis, Davis, California, USA.
- William R. Pritchard Veterinary Medical Teaching Hospital, University of California-Davis, Davis, California, USA.
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California-Davis, Davis, California, USA.
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California-Davis, Davis, California, USA.
- Department of Population Health and Reproduction, School of Veterinary Medicine, University of California-Davis, Davis, California, USA.
MeSH Terms
- Animals
- Horses
- Retrospective Studies
- Case-Control Studies
- Hospitals, Animal
- Colic / veterinary
- Prevalence
- Hospitals, Teaching
- Salmonella Infections, Animal / epidemiology
- Horse Diseases / epidemiology
- Horse Diseases / etiology
- Feces
- Salmonella
- Risk Factors
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Citations
This article has been cited 5 times.- Amory H, Cesarini C, De Maré L, Loublier C, Moula N, Detilleux J, Saulmont M, Garigliany MM, Lecoq L. Relationship between the Cycle Threshold Value (Ct) of a Salmonella spp. qPCR Performed on Feces and Clinical Signs and Outcome in Horses. Microorganisms 2023 Jul 30;11(8).
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- Bishop RC, Arrington JV, Wilkins PA, McCoy AM. Alterations in the Peritoneal Fluid Proteome of Horses with Colic Attributed to Ischemic and Non-Ischemic Intestinal Disease. Animals (Basel) 2025 May 30;15(11).
- Kabir A, Kelley WG, Glover C, Erol E, Helmy YA. Phenotypic and genotypic characterization of antimicrobial resistance and virulence profiles of Salmonella enterica serotypes isolated from necropsied horses in Kentucky. Microbiol Spectr 2025 Mar 4;13(3):e0250124.
- Karodia AB, Shaik T, Qekwana DN. Occurrence of Salmonella spp. in animal patients and the hospital environment at a veterinary academic hospital in South Africa. Vet World 2024 Apr;17(4):922-932.