Isolation, identification and virulence determinants of Streptococcus agalactiae from bovine subclinical mastitis in Egypt

Introduction: This study aimed to investigate the prevalence of contagious mastitis caused by Streptococcus agalctiae (S. agalactiae) in cattle from households and small-scale dairy farms in Egypt. Molecular characterization of S.agalactiae isolates was described including the genetic determinants...

Full description

Saved in:
Bibliographic Details
Main Authors: Khaled Abd EL-Hamid Abd El-Razik, Amany A Arafa, Ehab A Fouad, Abdelgayed M Younes, Abdulaziz M Almuzaini, Amr M Abdou
Format: Article
Language:English
Published: The Journal of Infection in Developing Countries 2021-08-01
Series:Journal of Infection in Developing Countries
Subjects:
Online Access:https://jidc.org/index.php/journal/article/view/12668
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850034371040378880
author Khaled Abd EL-Hamid Abd El-Razik
Amany A Arafa
Ehab A Fouad
Abdelgayed M Younes
Abdulaziz M Almuzaini
Amr M Abdou
author_facet Khaled Abd EL-Hamid Abd El-Razik
Amany A Arafa
Ehab A Fouad
Abdelgayed M Younes
Abdulaziz M Almuzaini
Amr M Abdou
author_sort Khaled Abd EL-Hamid Abd El-Razik
collection DOAJ
description Introduction: This study aimed to investigate the prevalence of contagious mastitis caused by Streptococcus agalctiae (S. agalactiae) in cattle from households and small-scale dairy farms in Egypt. Molecular characterization of S.agalactiae isolates was described including the genetic determinants of virulence to assess the genetic variation in isolated strains of S. agalactiae. Methodology: Three hundred and sixty milk samples were collected from 90 apparently healthy dairy cows randomly selected from household and small-scale dairy farms were examined by Somatic Cell Count (SCC) as an indicator for subclinical mastitis. S.agalactiae isolates were bacteriologically and molecularly identified followed by identification of virulence genes using PCR. Results: A total of 172 milk samples (47.77%) were positive with SCC > 200×103/ml. Bacteriological examination of the positive SCC milk samples revealed that 28 (16.28%) of the isolates were S.agalactiae. Molecular examination using PCR confirmed only 22 isolates of S. agalactiae (12.8%). Moreover, we used the pattern of virulence genes to address the genetic variation of S. agalactiae strains isolated from cases of contagious mastitis in cattle in Egypt. Virulence genes hylB, cylE, iagA, and bac were determined in 100%, 68.2%, 13.6% and 100% of isolates respectively. Conclusions: The use of molecular methods for the identification of the causative agent in mastitis confirmed that, in Egypt, Streptococcus agalactiae is considered as one of the predominant infectious agents among contagious mastitis causing pathogens. The pattern of virulence genes presented the genetic diversity of highly virulent S. agalactiae strains isolated from cases of contagious mastitis in cattle in Egypt.
format Article
id doaj-art-87f0470ee3bf475282da83d5cf42ba53
institution DOAJ
issn 1972-2680
language English
publishDate 2021-08-01
publisher The Journal of Infection in Developing Countries
record_format Article
series Journal of Infection in Developing Countries
spelling doaj-art-87f0470ee3bf475282da83d5cf42ba532025-08-20T02:57:52ZengThe Journal of Infection in Developing CountriesJournal of Infection in Developing Countries1972-26802021-08-01150810.3855/jidc.12668Isolation, identification and virulence determinants of Streptococcus agalactiae from bovine subclinical mastitis in EgyptKhaled Abd EL-Hamid Abd El-Razik0Amany A Arafa1Ehab A Fouad2Abdelgayed M Younes3Abdulaziz M Almuzaini4Amr M Abdou5Department of Animal Reproduction, National Research Center, Giza, EgyptDepartment of Microbiology and Immunology, National Research Center, Giza, EgyptDepartment of Microbiology and Immunology, National Research Center, Giza, EgyptDepartment of Hydrobiology, National Research Center, Giza, EgyptDepartment of Veterinary Medicine, College of Agriculture and Veterinary Medicine, Qassim University, Buraydah, Saudi ArabiaDepartment of Microbiology and Immunology, National Research Center, Giza, Egypt Introduction: This study aimed to investigate the prevalence of contagious mastitis caused by Streptococcus agalctiae (S. agalactiae) in cattle from households and small-scale dairy farms in Egypt. Molecular characterization of S.agalactiae isolates was described including the genetic determinants of virulence to assess the genetic variation in isolated strains of S. agalactiae. Methodology: Three hundred and sixty milk samples were collected from 90 apparently healthy dairy cows randomly selected from household and small-scale dairy farms were examined by Somatic Cell Count (SCC) as an indicator for subclinical mastitis. S.agalactiae isolates were bacteriologically and molecularly identified followed by identification of virulence genes using PCR. Results: A total of 172 milk samples (47.77%) were positive with SCC > 200×103/ml. Bacteriological examination of the positive SCC milk samples revealed that 28 (16.28%) of the isolates were S.agalactiae. Molecular examination using PCR confirmed only 22 isolates of S. agalactiae (12.8%). Moreover, we used the pattern of virulence genes to address the genetic variation of S. agalactiae strains isolated from cases of contagious mastitis in cattle in Egypt. Virulence genes hylB, cylE, iagA, and bac were determined in 100%, 68.2%, 13.6% and 100% of isolates respectively. Conclusions: The use of molecular methods for the identification of the causative agent in mastitis confirmed that, in Egypt, Streptococcus agalactiae is considered as one of the predominant infectious agents among contagious mastitis causing pathogens. The pattern of virulence genes presented the genetic diversity of highly virulent S. agalactiae strains isolated from cases of contagious mastitis in cattle in Egypt. https://jidc.org/index.php/journal/article/view/12668S.agalctiaeSubclinical mastitisVirulence genesPCR
spellingShingle Khaled Abd EL-Hamid Abd El-Razik
Amany A Arafa
Ehab A Fouad
Abdelgayed M Younes
Abdulaziz M Almuzaini
Amr M Abdou
Isolation, identification and virulence determinants of Streptococcus agalactiae from bovine subclinical mastitis in Egypt
Journal of Infection in Developing Countries
S.agalctiae
Subclinical mastitis
Virulence genes
PCR
title Isolation, identification and virulence determinants of Streptococcus agalactiae from bovine subclinical mastitis in Egypt
title_full Isolation, identification and virulence determinants of Streptococcus agalactiae from bovine subclinical mastitis in Egypt
title_fullStr Isolation, identification and virulence determinants of Streptococcus agalactiae from bovine subclinical mastitis in Egypt
title_full_unstemmed Isolation, identification and virulence determinants of Streptococcus agalactiae from bovine subclinical mastitis in Egypt
title_short Isolation, identification and virulence determinants of Streptococcus agalactiae from bovine subclinical mastitis in Egypt
title_sort isolation identification and virulence determinants of streptococcus agalactiae from bovine subclinical mastitis in egypt
topic S.agalctiae
Subclinical mastitis
Virulence genes
PCR
url https://jidc.org/index.php/journal/article/view/12668
work_keys_str_mv AT khaledabdelhamidabdelrazik isolationidentificationandvirulencedeterminantsofstreptococcusagalactiaefrombovinesubclinicalmastitisinegypt
AT amanyaarafa isolationidentificationandvirulencedeterminantsofstreptococcusagalactiaefrombovinesubclinicalmastitisinegypt
AT ehabafouad isolationidentificationandvirulencedeterminantsofstreptococcusagalactiaefrombovinesubclinicalmastitisinegypt
AT abdelgayedmyounes isolationidentificationandvirulencedeterminantsofstreptococcusagalactiaefrombovinesubclinicalmastitisinegypt
AT abdulazizmalmuzaini isolationidentificationandvirulencedeterminantsofstreptococcusagalactiaefrombovinesubclinicalmastitisinegypt
AT amrmabdou isolationidentificationandvirulencedeterminantsofstreptococcusagalactiaefrombovinesubclinicalmastitisinegypt