Pathological characteristics of olive flounder Paralichthys olivaceus experimentally infected with Streptococcus parauberis

Pathological characteristics of olive flounder Paralichthys olivaceus experimentally infected with Streptococcus parauberis were studied. Various stressful conditions, aeration and netting stress in particular, led to induced mortality by S. parauberis . Netting stress-induced mortality was positively correlated to bacterial dose and stressful conditions. Inflammation of the heart and pericarditis was the major pathological change observed in olive flounder experimentally infected with S. parauberis . During the infected period, the number of bacteria in the infected olive flounder was recorded over time. S. parauberis remained in all fish organs tested, especially in the heart and brain.