Diseases problems in cluttered sea bass Dicentrarchus Labrax reared in cages from Fingerlings until marketing size in Mariout Valley at King Mariout in Alexandria province

Abstract

This study aimed to determine and identify the common bacterial infection in different stages of cultured sea bass during the different season. In addition Eexperimentally infected the sea bass with the Vibrio alginolyticus and Vibrio parahemolyticus. The aquarium trial was carried out with European seabass (Dicentrarchus labrax) in private fish farm at Borg El-Arab, Alexandria governorate Egypt. At total 50 of seabass was used during the study. The study lasted 10 weeks, starting with 50 ± 5 gram /fish. Prior to the start of the trial, the fish were fed with a commercial diet (45 percent CP, crude protein). Water quality parameters were monitored during fish acclimatization and throughout the trial. Water temperature, pH and dissolved oxygen remained within acceptable ranges for marine production during the trial. Our study concluded that, Vibrio alginolyticus and Vibrio parahemolyticus causes a great losses in cluttered sea bass Dicentrarchus Labrax reared in cages The presence of histopathological lesions in the internal organs clearly explained the septicemic nature of Vibrio infection. Altogether, the full confirmation of Vibrio infection ought to incorporate, examination of fishes for the visible clinical signs, postmortem examination, isolation of the causative agent using specific media and biochemical tests, and histopathological examination of the internal organs as a proof of septicemic nature of the Vibrio infection. The sensitivity test revealed sensitive to ciprofloxacin (Cipro 5μg), novobiocine (NV 30 μg), intermediate sensitivity was found to Oxytetracycline (OT 30 μg) while, the resistance was observed to amoxicillin (Aml 10 μg) and colisitine sulphate (CT 10 μg)