Diversity and antimicrobial susceptibility profiling of staphylococci isolated from bovine mastitis cases and close human contacts

Show simple item record

dc.contributor.author Schmidt, Tracy
dc.contributor.author Kock, Marleen M.
dc.contributor.author Ehlers, M.M. (Marthie Magdaleen)
dc.date.accessioned 2015-09-18T11:12:25Z
dc.date.issued 2015-09
dc.description.abstract The objectives of this study were to examine the diversity of Staphylococcus spp. recovered from bovine intramammary infections and humans working in close contact with the animals and to evaluate the susceptibility of the staphylococcal isolates to different antimicrobials. A total of 3,387 milk samples and 79 human nasal swabs were collected from 13 sampling sites in the KwaZulu-Natal province of South Africa. In total, 146 Staph. aureus isolates and 102 coagulase-negative staphylococci (CNS) were recovered from clinical and subclinical milk samples. Staphylococcus aureus was isolated from 12 (15.2%) of the human nasal swabs and 95 representative CNS were recovered for further characterization. The CNS were identified using multiplex- PCR assays, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), and tuf gene sequencing. Seven Staphylococcus spp. were identified among the CNS of bovine origin, with Staph. chromogenes (78.4%) predominating. The predominant CNS species recovered from the human nasal swabs was Staph. epidermidis (80%) followed by Staph. chromogenes (6.3%). The antimicrobial susceptibility of all staphylococcal isolates was evaluated using disk diffusion and was supplemented by screening for specific antimicrobial resistance genes. Ninety-eight (67.1%) Staph. aureus isolates of bovine origin were pansusceptible; 39 (26.7%) isolates were resistant to a single class, and 7 (4.8%) isolates were resistant to 2 classes of antimicrobials. Two Staph. aureus (1.4%) isolates were multidrug-resistant. Resistance to penicillin was common, with 28.8% of the bovine and 75% of the human Staph. aureus isolates exhibiting resistance. A similar observation was made with the CNS, where 37.3% of the bovine and 89.5% of the human isolates were resistant to penicillin. Multidrug-resistance was common among the human CNS, with 39% of the isolates exhibiting resistance to 3 or more classes of antimicrobials. The antimicrobial susceptibility results suggest that resistance among staphylococci causing bovine intramammary infections in South Africa is uncommon and not a significant cause for concern. In contrast, antimicrobial resistance was frequently observed in staphylococcal isolates of human origin, highlighting a possible reservoir of resistance genes. Continued monitoring of staphylococcal isolates is warranted to monitor changes in the susceptibility of isolates to different classes of antimicrobials. en_ZA
dc.description.embargo 2016-09-30
dc.description.librarian hb2015 en_ZA
dc.description.sponsorship University of Pretoria, RESCOM, the National Research Foundation (NRF) of South Africa, and the KZN Department of Agriculture & Rural Development (South Africa). en_ZA
dc.description.uri http://www.journals.elsevier.com/journal-of-dairy-science en_ZA
dc.identifier.citation Schmidt, T, Kock, MM & Ehlers, MM 2015, 'Diversity and antimicrobial susceptibility profiling of staphylococci isolated from bovine mastitis cases and close human contacts', Journal of Dairy Science, vol. 98, no. 9, pp. 6256-6269. en_ZA
dc.identifier.issn 0022-0302 (print)
dc.identifier.issn 1525-3198 (online)
dc.identifier.other 10.3168/jds.2015-9715
dc.identifier.uri http://hdl.handle.net/2263/49988
dc.language.iso en en_ZA
dc.publisher American Dairy Science Association en_ZA
dc.rights © American Dairy Science Association®, 2015. Published by the Federation of Animal Science Societies and Elsevier Inc. All rights reserved. en_ZA
dc.subject Staphylococcus spp. en_ZA
dc.subject Bovine mastitis en_ZA
dc.subject Antimicrobial resistance en_ZA
dc.subject Close human contact en_ZA
dc.title Diversity and antimicrobial susceptibility profiling of staphylococci isolated from bovine mastitis cases and close human contacts en_ZA
dc.type Postprint Article en_ZA


Files in this item

This item appears in the following Collection(s)

Show simple item record