title: Species-level identification of staphylococci isolated from bovine mastitis in Brazil using partial 16S rRNA sequencing.
abstract: Staphylococci isolated from bovine milk and not classified as Staphylococcus aureus represent a heterogeneous group of microorganisms that are frequently associated with bovine mastitis. The identification of these microorganisms is important, although it is difficult and relatively costly. Genotypic methods add precision in the identification of Staphylococcus species. In the present study, partial 16S rRNA sequencing was used for the species identification of coagulase-positive and coagulase-negative staphylococci isolated from bovine mastitis. Two hundred and two (95%) of the 213 isolates were successfully identified at the species level. The assigning of an isolate to a particular species was based on ≥99% identity with 16S rRNA sequences deposited in GenBank. The identified isolates belonged to 13 different Staphylococcus species; Staphylococcus chromogenes, S. aureus and Staphylococcus epidermidis were the most frequently identified species. Eight isolates could not be assigned to a single species, as the obtained sequences showed 99% or 100% similarity to sequences from two or three different Staphylococcus species. The relatedness of these isolates with the other isolates and reference strains was visualized using a cladogram. In conclusion, 16S rRNA sequencing was an objective and accurate method for the proper identification of Staphylococcus species isolated from bovine mastitis. Additional target genes could be used in non-conclusive cases for the species-level identification of these microorganisms.
authors.affiliation: Embrapa Gado de Leite, Rua Eugênio do Nascimento 610, 36038-330 Juiz de Fora, Minas Gerais, Brazil. Electronic address: carla.lange@embrapa.br.
authors.forename: Carla C
authors.initials: CC
authors.lastname: Lange
authors.affiliation: Embrapa Gado de Leite, Rua Eugênio do Nascimento 610, 36038-330 Juiz de Fora, Minas Gerais, Brazil.
authors.forename: Maria A V P
authors.initials: MA
authors.lastname: Brito
authors.affiliation: Embrapa Gado de Leite, Rua Eugênio do Nascimento 610, 36038-330 Juiz de Fora, Minas Gerais, Brazil.
authors.forename: Daniele R L
authors.initials: DR
authors.lastname: Reis
authors.affiliation: Embrapa Gado de Leite, Rua Eugênio do Nascimento 610, 36038-330 Juiz de Fora, Minas Gerais, Brazil.
authors.forename: Marco A
authors.initials: MA
authors.lastname: Machado
authors.affiliation: Embrapa Gado de Leite, Rua Eugênio do Nascimento 610, 36038-330 Juiz de Fora, Minas Gerais, Brazil.
authors.forename: Alessandro S
authors.initials: AS
authors.lastname: Guimarães
authors.affiliation: Embrapa Gado de Leite, Rua Eugênio do Nascimento 610, 36038-330 Juiz de Fora, Minas Gerais, Brazil.
authors.forename: Ana L S
authors.initials: AL
authors.lastname: Azevedo
authors.affiliation: Rua Quintino Bocaiúva 131/402, 31255-550 Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Érica B
authors.initials: ÉB
authors.lastname: Salles
authors.affiliation: Universidade Federal de Juiz de Fora, Rua José Lourenço Kelmer, 36036-330 Juiz de Fora, Minas Gerais, Brazil.
authors.forename: Mariana C T
authors.initials: MC
authors.lastname: Alvim
authors.affiliation: Centro de Ensino Superior de Juiz de Fora, Av. Luz Interior 345, 36030-776 Juiz de Fora, Minas Gerais, Brazil.
authors.forename: Fabiana S
authors.initials: FS
authors.lastname: Silva
authors.affiliation: Universidade Federal de Juiz de Fora, Rua José Lourenço Kelmer, 36036-330 Juiz de Fora, Minas Gerais, Brazil.
authors.forename: Igor R
authors.initials: IR
authors.lastname: Meurer
mesh_terms: D000818:Animals; D001483:Base Sequence; D001938:Brazil; D002417:Cattle; D003030:Coagulase / Q000378:metabolism; D005260:Female; D005838:Genotype; D008414:Mastitis, Bovine / Q000382:microbiology*; D008892:Milk / Q000382:microbiology*; D008969:Molecular Sequence Data; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA / Q000662:veterinary; D017385:Sequence Homology; D013045:Species Specificity; D013210:Staphylococcus / Q000235:genetics*
chemical_list: D003030:Coagulase; D012336:RNA, Ribosomal, 16S
keywords: Coagulase-negative staphylococci; S. agnetis; S. aureus; S. chromogenes; S. devriesei; Tube coagulase test