African Journal of
Microbiology Research

  • Abbreviation: Afr. J. Microbiol. Res.
  • Language: English
  • ISSN: 1996-0808
  • DOI: 10.5897/AJMR
  • Start Year: 2007
  • Published Articles: 5232

Full Length Research Paper

Denaturing gradient gel electrophoresis (DGGE): An alternative culture independent method for bacterial screening in bovine milk sample

Bruno Oliveira de Carvalho
  • Bruno Oliveira de Carvalho
  • Veterinary Microbiology and Immunology Department, Universidade Federal Rural do Rio de Janeiro, Brazil.
  • Google Scholar
Danilo Alves de França
  • Danilo Alves de França
  • Department of Veterinary Hygiene and Public Health, São Paulo State University "Júlio de Mesquita Filho", Botucatu, São Paulo, Brazil.
  • Google Scholar
Dayanne Araújo de Melo
  • Dayanne Araújo de Melo
  • Veterinary Microbiology and Immunology Department, Universidade Federal Rural do Rio de Janeiro, Brazil.
  • Google Scholar
Shana de Mattos de Oliveira Coelho
  • Shana de Mattos de Oliveira Coelho
  • Veterinary Microbiology and Immunology Department, Universidade Federal Rural do Rio de Janeiro, Brazil.
  • Google Scholar
Irene da Silva Coelho
  • Irene da Silva Coelho
  • Veterinary Microbiology and Immunology Department, Universidade Federal Rural do Rio de Janeiro, Brazil.
  • Google Scholar
Miliane Moreira Soares de Souza
  • Miliane Moreira Soares de Souza
  • Veterinary Microbiology and Immunology Department, Universidade Federal Rural do Rio de Janeiro, Brazil.
  • Google Scholar


  •  Received: 27 July 2022
  •  Accepted: 10 January 2023
  •  Published: 30 November 2023

Abstract

Bovine mastitis is a disease that has a great impact on Brazilian livestock production. Some bacteria described as mastitis-causing agents are not easily cultivable in conventional media, making their diagnosis difficult. The aim of the present study was to detect bacteria present in milk from mastitic and non-mastitic quarters of dairy cattle in Rio de Janeiro-Brazil, using a culture-independent and culture-dependent method. Milk samples were collected from healthy and mastitic quarters. Blood agar medium was used to isolate bacteria. Polymerase Chain Reaction - Denaturing Gradient Gel Electrophoresis (PCR-DGGE) followed by gene sequencing was used to detect bacterial species. Bacteria were isolated from 12 milk samples and Staphylococcus aureus was the only species identified. Bands unique to mastitis were detected in some animals, signaling possible causative agents of the disease in the herd. Species of the genus Streptococcus identified in these samples could not be isolated in culture medium. The present study concluded that the DGGE technique proved to be efficient in detecting bacteria that have difficulty growing in culture medium.

 

Key words: Bovine mastitis, polymerase chain reaction, Staphylococcus aureus, Streptococcus.