Detection and enumeration of Staphylococcus aureus from bovine milk samples by real-time polymerase chain reaction
| Autor: | José Franchini Garcia Moreno, Luis Felipe Prada e Silva, Marcos Veiga dos Santos, Cristina Simões Cortinhas, Bruno Garcia Botaro, Nilson Roberti Benites, L.V. Março |
|---|---|
| Rok vydání: | 2013 |
| Předmět: |
Staphylococcus aureus
Serial dilution Biology medicine.disease_cause Real-Time Polymerase Chain Reaction Sensitivity and Specificity Microbiology fluids and secretions Anti-Infective Agents Genetics medicine Enumeration Animals Micrococcal Nuclease Mastitis Bovine Detection limit food and beverages Reproducibility of Results Raw milk Staphylococcal Infections Isolation (microbiology) Standard curve Real-time polymerase chain reaction Milk Propylene Glycols Animal Science and Zoology Cattle Female Food Science |
| Zdroj: | Journal of dairy science. 96(11) |
| ISSN: | 1525-3198 |
| Popis: | The aim of this study was to develop and evaluate a real-time quantitative PCR (qPCR)-based method to detect and quantify Staphylococcus aureus in bronopol-preserved milk samples from subclinical intramammary infections (IMI). Serial dilutions of milk artificially inoculated with Staph. aureus ATCC 29213 were used to establish a standard curve (cfu/mL) of the qPCR assay targeting the Staph. aureus thermonuclease-encoding gene nuc according to the strain plate count. The analytical sensitivity, specificity, and repeatability of the qPCR assay were determined. A total of 60 milk samples, collected from mammary quarters without abnormal appearance and with positive isolation of Staph. aureus, were submitted to both the qPCR protocol and Staph. aureus plate counting and results from both methods were compared. Staphylococcus aureus from bronopol-preserved, subclinical IMI milk samples were not accurately enumerated by qPCR compared with plate counting of the nonpreserved, raw milk sample. The detection limit of the qPCR protocol of inoculated Staph. aureus ATCC 29213 in bronopol-preserved milk samples was 1.04 × 10(1) cfu/mL. The qPCR protocol can be a high-throughput and rapid diagnostic assay to accurately detect Staph. aureus IMI from bronopol-preserved milk samples compared with a traditional culturing method. However, the proposed qPCR protocol is not accurate for counting of Staph. aureus in bronopol-preserved milk samples from naturally infected mammary glands. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|