Genetic diversity and virulence genes in Streptococcus uberis strains isolated from bovine mastitis
DOI:
https://doi.org/10.5433/1679-0359.2017v38n4Supl1p2595Keywords:
Bovine diseases, Environmental Streptococci, Intramammary infections, PFGE, Streptococci virulence.Abstract
Mastitis is one of the most common and costly infectious diseases in dairy cattle worldwide. This is a multifactorial illness caused by different microorganisms, including virus, yeasts, algae, parasites, and several species of bacteria. Among these bacteria, Streptococcus uberis is an important environmental pathogen that is responsible for a large range of clinical and subclinical mammary infections, especially in intensively managed herds. Despite the increasing importance of this pathogen in the etiology of bovine mastitis, data on its virulence and diversity in Brazilian dairy herds are scarce. The aims of the present study were to investigate the virulence characteristics of S. uberis isolated from bovine mastitis and to assess the molecular epidemiology of the Brazilian isolates using pulsed-field gel electrophoresis (PFGE). In this work, 46 strains of S. uberis isolated from bovine mastitis from 26 Brazilian dairy herds were evaluated regarding their genetic diversity by PFGE using with the SmaI enzyme. Additionally, the presence of the virulence genes skc and pauA, which encode plasminogen activators, and the gene sua, which encodes an adhesion molecule in mammary epithelial cells, were assessed by PCR. Our results showed a high genetic diversity in the population, displaying many different patterns in the PFGE analysis. A high proportion of strains was positive for virulence genes in the sampled population (sua [100%], pauA [91%], and skc [91%]). The high frequency of skc, pauA, and sua genes among the studied strains suggests the importance of these virulence factors, possibly helping S. uberis in the colonization of the bovine mammary gland. Surveys of the genetic and molecular characteristics of this pathogen can improve our knowledge of bacterial activity and identify molecules that have roles in the establishment of the infection. This might help in the development of more effective measures to control and prevent bovine mastitis.Downloads
Downloads
Published
How to Cite
Issue
Section
License
Copyright (c) 2017 Semina: Ciências Agrárias
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
Semina: Ciências Agrárias adopts the CC-BY-NC license for its publications, the copyright being held by the author, in cases of republication we recommend that authors indicate first publication in this journal.
This license allows you to copy and redistribute the material in any medium or format, remix, transform and develop the material, as long as it is not for commercial purposes. And due credit must be given to the creator.
The opinions expressed by the authors of the articles are their sole responsibility.
The magazine reserves the right to make normative, orthographic and grammatical changes to the originals in order to maintain the cultured standard of the language and the credibility of the vehicle. However, it will respect the writing style of the authors. Changes, corrections or suggestions of a conceptual nature will be sent to the authors when necessary.
