First case report of Corynebacterium pseudotuberculosis biovar equi in semiarid region of Brazil.
Abstract: Corynebacterium pseudotuberculosis is a bacterium that causes significant economic damage to farmers, mainly in the semiarid region of Northeastern Brazil. In this context, only biovar ovis has been reported, and it is widespread in small ruminants. However, this report describes the first equine case in Brazil attributable to a biovar equi. Clinically, it is the causative agent of ulcerative lymphangitis, mastitis, necrotic and ulcerative dermatitis. A Quarter Horse from the semiarid Northeast presented ulcerative lymphangitis. Culture, nitrate reduction test, MALDI-TOF, and whole-genome sequencing identified the Cp_Eq_BR01 strain as biovar equi. The 2.37 Mb genome shared > 98% nucleotide identity with other equi strains and clustered most closely with the Chilean isolate E19. Although no unique determinants of virulence or resistance were found, the observed genomic clonality suggests potential for rapid transboundary spread. This first Brazilian detection broadens the recognized host range, alerts the farmer's national equine to a new threat, and highlights the need for routine nitrate testing, and updated movement control policies for equines.
© 2025. The Author(s) under exclusive licence to Sociedade Brasileira de Microbiologia.
Publication Date: 2025-07-01 PubMed ID: 40593302PubMed Central: 5026146DOI: 10.1007/s42770-025-01723-9Google Scholar: Lookup
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Summary
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The research article discusses the first reported case of a bacterium, Corynebacterium pseudotuberculosis biovar equi, impacting a horse within the semiarid region of Northeast Brazil.
Background of the Study
- The research was conducted in response to the presence of the bacterium Corynebacterium pseudotuberculosis in the semiarid region of Northeast Brazil, which has reportedly caused significant economic loss to farmers, particularly those raising small ruminants.
- Prior to this study, reports from this region indicated infections with the biovar ovis, but not biovar equi, of this bacterium.
Case Description
- The creature infected with biovar equi as discussed in this report was a Quarter Horse from the same semiarid region.
- The horse presented with ulcerative lymphangitis, a condition known to be caused by this bacterium. This condition was also observed in the form of mastitis and necrotic and ulcerative dermatitis.
Identification of the Bacteria
- The researchers used a variety of methods to identify the bacterium, including culture, a nitrate reduction test, MALDI-TOF (Matrix Assisted Laser Desorption Ionisation – Time of Flight Mass Spectrometry), and whole-genome sequencing.
- The specific strain of bacteria identified was Cp_Eq_BR01, which was classified as biovar equi.
Genome Analysis
- The genome of this strain was found to be 2.37 Mb in size and had a nucleotide identity greater than 98% when compared with other equi strains. This was most closely clustered with a Chilean isolate identified as E19.
- No unique virulence or resistance identifiers were found in this strain, however the genomic clonality observed suggests the potential for this strain to spread quickly across borders.
Implications of the Study
- This research expands the current understanding of the host range for this bacteria within Brazil and represents the first detection of this strain in a horse within the country.
- This discovery highlights a new threat to Brazil’s national equine population and emphasises the importance of implementing routine nitrate testing and updating movement control policies for horses in this region to prevent further spread of this bacterium.
Cite This Article
APA
de Souza Lima E, de Oliveira Filho RB, Malta KC, Pires IC, Rosa DS, Chideroli RT, Aburjaile FF, de Jesus Sousa T, Ramos RTJ, Góes-Neto A, de Castro Soares S, Brenig B, de Carvalho Azevedo VA, da Costa MM, de Carvalho Fernandes AC.
(2025).
First case report of Corynebacterium pseudotuberculosis biovar equi in semiarid region of Brazil.
Braz J Microbiol.
https://doi.org/10.1007/s42770-025-01723-9 Publication
Researcher Affiliations
- Laboratory of Preventive Veterinary Medicine, Veterinary Science Department, Universidade Federal da Paraíba, Areia, Paraíba, Brazil.
- Veterinary Hospital, Center of Agrarian Sciences, Universidade Federal da Paraíba, Areia, Paraíba, Brazil.
- Laboratory of Preventive Veterinary Medicine, Veterinary Science Department, Universidade Federal da Paraíba, Areia, Paraíba, Brazil.
- Veterinary Hospital, Center of Agrarian Sciences, Universidade Federal da Paraíba, Areia, Paraíba, Brazil.
- Laboratory of Preventive Veterinary Medicine, Veterinary Science Department, Universidade Federal da Paraíba, Areia, Paraíba, Brazil.
- Veterinary Hospital, Center of Agrarian Sciences, Universidade Federal da Paraíba, Areia, Paraíba, Brazil.
- Universidade Federal do Vale do São Francisco, Av. José de Sá Maniçoba, S/N, Centro, Petrolina, CEP: 56304-917, Pernambuco, Brazil.
- Universidade Federal do Vale do São Francisco, Av. José de Sá Maniçoba, S/N, Centro, Petrolina, CEP: 56304-917, Pernambuco, Brazil.
- Universidade Federal do Vale do São Francisco, Av. José de Sá Maniçoba, S/N, Centro, Petrolina, CEP: 56304-917, Pernambuco, Brazil.
- Preventive Veterinary Medicine Departament, Veterinary School, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
- Laboratory of Cellular and Molecular Genetics, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
- Laboratory of Biological Engineering, Science and Technology Park Guama, Belém, Pará, Brazil.
- Laboratory of Molecular and Computational Biology of Fungi, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
- Laboratory of Immunology and Bioinformatics, Institute of Biological and Natural Sciences, Federal University of Triangulo Mineiro, Uberaba, Minas Gerais, Brazil.
- Department of Molecular Biology of Livestock, Institute of Veterinary Medicine, Georg August University Göttingen, Göttingen, Germany.
- Laboratory of Cellular and Molecular Genetics, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
- Universidade Federal do Vale do São Francisco, Av. José de Sá Maniçoba, S/N, Centro, Petrolina, CEP: 56304-917, Pernambuco, Brazil. mmatiuzzicosta@gmail.com.
- Laboratory of Preventive Veterinary Medicine, Veterinary Science Department, Universidade Federal da Paraíba, Areia, Paraíba, Brazil.
- Veterinary Hospital, Center of Agrarian Sciences, Universidade Federal da Paraíba, Areia, Paraíba, Brazil.
Grant Funding
- Financing Code 001 / Coordenau00e7u00e3o de Aperfeiu00e7oamento de Pessoal de Nu00edvel Superior
- APQ-0587-5.05/15 / Fundau00e7u00e3o de Amparo u00e0 Ciu00eancia e Tecnologia do Estado de Pernambuco
- APQ-0474-5.05/19 / Fundau00e7u00e3o de Amparo u00e0 Ciu00eancia e Tecnologia do Estado de Pernambuco
- IBPG-1650-2.00/21 / Fundau00e7u00e3o de Amparo u00e0 Ciu00eancia e Tecnologia do Estado de Pernambuco
Conflict of Interest Statement
Declarations. Conflict of interest: The authors declare no conflicts of interest.
References
This article includes 19 references
- Dorella FA, Pacheco LGC, Oliveira SC, Miyoshi A, Azevedo V. Corynebacterium pseudotuberculosis: microbiology, biochemical properties, pathogenesis and molecular studies of virulence.. Vet Res 37:201–218.
- Baird GJ, Fontaine MC. Corynebacterium pseudotuberculosis and its role in ovine caseous lymphadenitis.. J Comp Pathol 137:179–210.
- Baraúna RA, Ramos RTJ, Veras AAO, de Sá PHCG, Guimarães LC, das Graças DA, Carneiro AR, Edman JM, Spier SJ, Azevedo V, Silva A. Genomic analysis of four strains of Corynebacterium pseudotuberculosis bv. Equi isolated from horses showing distinct signs of infection.. Stand Genom Sci 12:1–16.
- de Oliveira Zamprogna T, Ribeiro D, Azevedo VAC, Lara GHB, Motta RG, da Silva RC, Siqueira AK, de Nardi Júnior G, Listoni FJP, Martins LSA, da Silva AV, Portilho FVR, Mota AR, Rodrigues CA, de Almeida BO, Ribeiro MG. Bacteriological, cytological, and molecular investigation of Corynebacterium pseudotuberculosis, mycobacteria, and other bacteria in caseous lymphadenitis and healthy lymph nodes of slaughtered sheep.. Braz J Microbiol 52:431–438.
- Haas DJ, Dorneles EMS, Spier SJ, Carroll SP, Edman J, Azevedo VA, Heinemann MB, Lage AP. Molecular epidemiology of Corynebacterium pseudotuberculosis isolated from horses in California.. Infect Genet Evol 49:186–194.
- Corbeil LE, Morrissey JF, Léguillette R. Is Corynebacterium pseudotuberculosis infection (pigeon fever) in horses an emerging disease in Western Canada?. Can Vet J 57:1062–1066.
- House RW, Schousboe M, Allen JP, Grant CC. Corynebacterium Ovis (pseudo-tuberculosis) lymphadenitis in a sheep farmer: a new occupational disease in New Zealand.. N Z Med J 99:659–662.
- Kilcoyne I, Spier SJ, Carter CN, Smith JL, Swinford AK, Cohen ND. Frequency of Corynebacterium pseudotuberculosis infection in horses across the United States during a 10-year period.. J Am Vet Med Assoc 245:309–314.
- Müller B, de Klerk-Lorist LM, Henton MM, Lane E, Parsons SG, van Pittius NC, Kotze A, van Helden PD, Tanner M. Mixed infections of Corynebacterium pseudotuberculosis and non-tuberculous mycobacteria in South African antelopes presenting with tuberculosis-like lesions.. Vet Microbiol 147:340–345.
- Connor KM, Quirie MM, Baird G, Donachie W. Characterization of United Kingdom isolates of Corynebacterium pseudotuberculosis using pulsed-field gel electrophoresis.. J Clin Microbiol 38:2633–2637.
- Paton M, Walker S, Rose I, Watt G. Prevalence of caseous lymphadenitis and usage of caseous lymphadenitis vaccines in sheep flocks.. Aust Vet J 81:91–95.
- Selim SA. Oedematous skin disease of Buffalo in Egypt.. J Vet Med B Infect Dis Vet Public Health 48:241–258.
- Silva A, Schneider MPC, Cerdeira L, Barbosa MS, Ramos RTJ, Carneiro AR. Complete genome sequence of Corynebacterium pseudotuberculosis I19, a strain isolated from a cow in Israel with bovine mastitis.. J Bacteriol 193:323–324.
- Cavalcante ALQ, Dias LM, Alves JTC, Veras AAO, Guimarães LC, Rocha FS, Gala-Garcia A, Retamal P, Ramos RTJ, Azevedo V, Silva A, Carneiro AR. Complete genome sequence of Corynebacterium pseudotuberculosis strain E19, isolated from a horse in Chile.. Genome Announc 3:1–2.
- Sellon DC, Spier SJ, Whitcomb MB, Arguedas MG, Long MT, Oaks JL, Hines MT. Chap. 45 - Miscellaneous bacterial infections.. Equine infectious diseases. Elsevier Saunders 2014:373–392.
- Quinn JP. Microbiologia veterinária e Doenças infecciosas.. Artmed, Porto Alegre pp 67–70.
- Spier SJ, Toth B, Edman J, Quave A, Habasha F, Garrick M, Byrne BA. Survival of Corynebacterium pseudotuberculosis biovar equi in soil.. Vet Rec 170:180.
- Guedes MT, Souza BC, Sousa TJ, Loureiro D, Moura-Costa LF, Azevedo V, Meyer R, Portela RW. Infecção Por Corynebacterium pseudotuberculosis Em equinos: aspectos microbiológicos, clínicos e preventivos.. Pesquisa Veterinária Brasileira 35:701–708.
- Spier S. AAEP infectious disease guidelines: pigeon fever (Corynebacterium pseudotuberculosis).. .
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