Outbreak of equine botulism type C associated with consumption of baleage in Brazil.
Abstract: An outbreak of botulism occurred in March 2024 among horses at a Quarter Horse stud farm in Central-West Brazil. After ingesting baleage, 22 of 26 (85%) horses housed in stables and fed baleage became ill. The affected horses had dysphagia, muscular weakness, fasciculations, and progressive recumbency; 13 of 22 (59%) died within a few days. The diagnosis of type C botulism was established based on clinical and epidemiologic findings and confirmed by mouse bioassays, which indicated botulinum toxin type C in liver samples and intestinal contents. Furthermore, PCR testing identified toxigenic in the baleage consumed by the horses.
Publication Date: 2026-01-08 PubMed ID: 41504204PubMed Central: PMC12783021DOI: 10.1177/10406387251399152Google Scholar: Lookup
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- Journal Article
Cite This Article
APA
Souza LL, Lima AS, Martins AS, Silva TA, Borsanelli AC, Dutra IS, Pupin RC, Gomes DC, Lemos RA.
(2026).
Outbreak of equine botulism type C associated with consumption of baleage in Brazil.
J Vet Diagn Invest, 38(2), 302-304.
https://doi.org/10.1177/10406387251399152 Publication
Researcher Affiliations
- Laboratory of Anatomical Pathology, Faculty of Veterinary Medicine and Animal Science, Federal University of Mato Grosso do Sul, Campo Grande, MS, Brazil.
- Laboratory of Anatomical Pathology, Faculty of Veterinary Medicine and Animal Science, Federal University of Mato Grosso do Sul, Campo Grande, MS, Brazil.
- Preventive Veterinary Medicine Sector, School of Veterinary Medicine and Animal Science, Federal University of Goiás, Goiânia, GO, Brazil.
- Preventive Veterinary Medicine Sector, School of Veterinary Medicine and Animal Science, Federal University of Goiás, Goiânia, GO, Brazil.
- Preventive Veterinary Medicine Sector, School of Veterinary Medicine and Animal Science, Federal University of Goiás, Goiânia, GO, Brazil.
- Department of Animal Production and Health, Araçatuba School of Veterinary Medicine, São Paulo State University, Araçatuba, Brazil.
- Laboratory of Anatomical Pathology, Faculty of Veterinary Medicine and Animal Science, Federal University of Mato Grosso do Sul, Campo Grande, MS, Brazil.
- Laboratory of Anatomical Pathology, Faculty of Veterinary Medicine and Animal Science, Federal University of Mato Grosso do Sul, Campo Grande, MS, Brazil.
- Laboratory of Anatomical Pathology, Faculty of Veterinary Medicine and Animal Science, Federal University of Mato Grosso do Sul, Campo Grande, MS, Brazil.
MeSH Terms
- Horses
- Animals
- Botulism / veterinary
- Botulism / epidemiology
- Botulism / microbiology
- Horse Diseases / epidemiology
- Horse Diseases / microbiology
- Horse Diseases / etiology
- Brazil / epidemiology
- Disease Outbreaks / veterinary
- Male
- Female
- Botulinum Toxins
- Clostridium botulinum / isolation & purification
- Mice
Conflict of Interest Statement
Declaration of conflicting interestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
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