I assume you're plating this on a selective medium that would get rid of
gram negatives, i.e. CNA blood agar (colistin/Nalidixic Acid added to
Columbia blood agar base - it's a common medium in clinical labs). I would
also plate on 5% TSA sheep blood agar but you'd probably pick up gram
negatives with this also.
Pick gamma or dark alpha/gamma colonies to a new blood plate (pick only ONE
colony to keep it pure). Label your isolates somehow so you know which one
is which. They should be catalase negative gram positive cocci. The classic
ID method for differentiating enterococci and Strep bovis is using bile
esculin agar and 6.5% salt broth. Once you have a plate full of overnight
growth you can inoculate a BE slant and a tube of salt broth for each colony
you pick. Incubate overnight. S. bovis should be BE+/6.5% NaCl -.
Enterococci are positive for both.
If you are using PYR discs, the protocol for S. bovis PYR negative--->BE
slant overnight. If PYR neg/BE+ then you probably have a S. bovis and can
continue on with further testing. I personally like the old fashioned
BE/NaCl broth method. You can cheaply screen a lot of colonies this way and
it is clear cut to read.
Once you screen via the BE/NaCl you can go on to further ID by API or GPI
Vitek Card if you'd like.
Judy Dilworth, M.T. (ASCP)
"tere" <teremxr from hotmail.com> wrote in message
news:1171883426.012915.119330 from l53g2000cwa.googlegroups.com...
>> I'm trying to identifiy Streptococcus bovis from colon tissues but I
> can't find a good protocol before use API strep test ( Biomerieux) to
> finally isolated it.
> please, do you know any protocol to identify it in the laboratory by
> classic methods?
>> thank you