I am currently failling in experiment to Streptococcus on fish. I really do not know the fish did not appear any clinical signs and was still healthy after I injected a determined dose of Strep. I now wonder wether the fish could immunise against that pathogen or virulent pathogen is not strong enough to kill the fish.
I am finding some way to test virulence of Streptococcus spp.. Can anyone who are well aware of that of Streptococcus help me, please?
Thank in advance!