Characterization of Vibrio Alginolyticus Infection in Gilthead Seabream (Sparus Auratus, L) Cultured in Egypt

Abstract

The present study investigated Vibriosis in cultured Gilthead Seabream at the Suez Canal area, Egypt. Two hundred moribund fish samples subjected to clinical, microbiological and histopathological examinations. Retrieved isolates were biochemically identified using API 20 E system then confirmed by conventional PCR. Antibiogram profiling of the retrieved isolates was also done.Naturally infected fish showed severe ascites, hemorrhages and erosions in the skin and fins.A sum of 29 V. alginolyticus isolates were retrieved from the examined samples. Targeting 16SrRNA and groEl genes produce an expected product with a length of 336, 301bp size bands; respectively, were found from all tested strains of V. alginolyticus. The antibiogram profiling of V. alginolyticus isolates showed resistance to Ampicillin, Gentamycin followed by Ciprofloxacin with high sensitivity to Sulphamethoxazole/Trimethoprim and oxytetracycline. Histopathological alterations in the affected tissues showed, inflammatory reactions together with degenerative and /or necrotic changes in branchial, liver and kidney. Ultimately, the current study emphasizes the critical fish health threats posed by V. alginolyticus with subsequent influences on human. Thus, competent biosecurity strategies should be adopted to control Vibrio infection in marine fishes and to minimize the antimicrobial resistance hazards in mariculture.