bacteriological studies on enterococcus faecalisin oreochromis niloticus

The present study was planned to investigate Enterococcosis incultured and wild Nile tilapia (Oreochromis niloticus)In this investigation 300 Nile tilapia (0. niloticus) collectedrandomly from different localities in different seasons of year in Egyptwere subjected to clinical and bacteriological examination to identifyand determine the prevalance of Enterococcus infection.The clinical picture of diseased fish characterized byhaemorrhages in the lower jaw, operculum, arround the mouth, vent,fin and skin with dettachment of scales, opacity in the eye, unilateralor bilateral exophthalmia, sluggish movement, respiratory disorderand abdominal destention.In the present study, 25 bacterial isolates of Enterococcus weredetected and identified as Enterococcus faecalis. The percentage ofinfection with Enterococcus faecalis in Wild tilapia was 23.3%It was found that the prevalence of Enterococcal infection amongWild fish in summer season 48.5%followed by (20%), (16%), (5.70/0)in spring, autumn and winter respectively.The percentage of infection was high in private fish farmsespecialy in Sahl El-Hosainia due to high pollution with faecal matter.