Fecal Shedding of Clostridioides difficile in Calves in Sao Paulo State, Brazil

Fabrício Moreira Cerri; Roberta Martins Basso; Wanderson Adriano Pereira Biscola; Júlia Meireles Silva; Eliane Oliveira Ferreira; Amanda Haisi; João Pessoa Araújo Júnior; Luis G Arroyo; Yasmin Gonçalves de Castro; Rodrigo Otávio Silveira Silva; José Paes de Oliveira Filho; Alexandre Secorun Borges

doi:10.1016/j.anaerobe.2024.102861

Fecal Shedding of Clostridioides difficile in Calves in Sao Paulo State, Brazil

Anaerobe. 2024 May 8:102861. doi: 10.1016/j.anaerobe.2024.102861. Online ahead of print.

Affiliations

¹ Sao Paulo State University (UNESP), School of Veterinary Medicine and Animal Science (FMVZ), Botucatu, Sao Paulo, Brazil.
² Federal University of Rio de Janeiro (UFRJ), Paulo de Góes Institute of Microbiology (IMPG), Department of Medical Microbiology, UFRJ, Rio de Janeiro, Rio Janeiro, Brazil.
³ Sao Paulo State University (UNESP), Institute of Biotechnology (IBTEC), Botucatu, Sao Paulo, Brazil.
⁴ University of Guelph, Ontario Veterinary College, Department of Clinical Studies, Guelph, Ontario, Canada.
⁵ Federal University of Minas Gerais (UFMG), School of Veterinary Medicine (EV), Belo Horizonte, Minas Gerais, Brazil.
⁶ Sao Paulo State University (UNESP), School of Veterinary Medicine and Animal Science (FMVZ), Botucatu, Sao Paulo, Brazil.. Electronic address: alexandre.s.borges@unesp.br.

PMID: 38729514
DOI: 10.1016/j.anaerobe.2024.102861

Abstract

Objective: This study aimed to evaluate the fecal shedding of C. difficile in calves on farms in Sao Paulo State, Brazil.

Materials and methods: Fecal samples (n=300) were collected from diarrheic (n=78) and nondiarrheic (n=222) calves less than 60 days of age from 20 farms. Fecal samples were inoculated into enrichment broth supplemented with taurocholate and cultured under anaerobic conditions. Colonies suspected to be C. difficile were harvested for DNA extraction and then multiplex PCR for the detection of genes encoding toxins A and B and binary toxins. All toxigenic isolates were ribotyped and tested for antimicrobial susceptibility, and five selected strains were subjected to whole-genome sequencing to determine their sequence type.

Results and discussion: C. difficile was isolated from 29.3% (88/300) of the samples. All toxigenic isolates (17/88, 19.3%) were classified as ribotypes RT046 (13/17 -79.47%, A⁺B⁺ CDT^-) and RT126 (4/17=20.53%, A⁺B⁺ CDT⁺). The sequenced strains from RT046 were classified as ST35 (Clade 1), while those from RT126 were classified as ST11 (Clade 5). No associations between the epidemiological factors in any of the groups and C. difficile isolation were observed. Most of the toxigenic isolates (16/17=94.41%) were classified as multidrug-resistant. Calves can be an important source of toxigenic C. difficile strains, including multidrug-resistant isolates from ribotypes commonly observed in humans.

Keywords: MLST; RT126; ST35; cattle; diarrhea.