2.5. Testing a nested-PCR's specificity and sensitivity for detecting S.
agalactiae in red tilapia tissue
The nested-PCR specificity was evaluated with purified genomic
DNA from S. agalactiae ST991 and ATCC12386 strains as template, as
well as total DNA obtained from fish muscle tissue inoculated with
S. agalactiae ST991 and with genomic DNA extracted from pure Streptococcus
pneumoniae, Enterococcus faecalis ATCC 49 619 29 272, Streptococcus
iniae MY001, Lactococcus garviae MY001, and Aeromonas
hydrophila KJ99 cultures. S. agalactiae ATCC 49 619 29 272 DNA
(obtained from a pure bacterial culture) was serially diluted and
each dilution was mixed with constant amounts of genomic DNA
extracted from frozen or from paraffin-wax-embedded healthy tilapia
brains to evaluate nested-PCR sensitivity in tissue.