Virulence genes contributing to pathogenicity in Nile tilapia (): approaching the development of live and inactivated vaccines.

This study aimed to develop and evaluate live and inactivated vaccines to pathogenicity in Nile tilapia. Therefore, five well-identified isolates, including A (HY1), A (HY2), A (HY3), A (HY4), and A (HY6) isolated from diseased Nile tilapia (), were used for vaccine preparation. Virulence genes detected by a polymerase chain reaction (PCR) and lethal dose determination were conducted.