POLYMERASE CHAIN REACTION IN COMPARISON WITH TRADITIONAL METHODS FOR DIAGNOSIS OF BACTERIAL DISEASES AMONG SOME MARINE FISHES IN DIFFERENT SEASONS

Ahmed S. Diab1; Ahmed M.A. Ammar2; Yousif Abdel Galil2;

Saleh F. Sakar1; Mohamed E. Abou Elatta1

And Taghrid M.N. Abd El-Hakim1

1Dept Of Fish Diseases And Management, CLAR, ARC, Egypt.

2Dept Of Microbiology And Immunity, Zagazig Vet. Med., Zagazig Univ.

Received 11/ 8/ 2013

Accepted 12/ 9/ 2013

Abstract

The present study was planned to investigate the most bacterial pathogens affecting some mariculture fishes. Diseases problems occurred maricultured fishes were investigated focusing on the isolation, characterization, antimicrobial resistance, pathogencity of the bacterial isolates affecting fish, histopathological alteration and PCR. Common clinical signs in examined fishes were hemorrhages, exophthalmia and darkness. Postmortem examination showed pale liver with hemorrhage, congested gills and ovaries. The microscopical result revealed finding revealed gill telangectasis, congestion of central vein, periductal fibrosis and lobulation of glomerrler tuft. The result for prevalence of the main pathogenic microorganisms revealed that Vibrio. alginolyticus (35%), V. anguillarum (25%) and V. paraheamolyticus (5%). Most of isolated strains were sensitive to ciprofloxacin, Nalidixic acid and sulphatrimethoprima. Physical water parameters were estimated and discussed. Maximum PCR detection of V. alginolyticus from 3 isolates Mugil capito and one isolate from Gilthead sea bream and one isolates from Sea bass were five field isolates were tested and all of them gave characteristic common bands.