Bacteriological Studies on Vibriosis in Egyptian Sole (Solea aegyptiaca) Fish

Abstract

The main objectives of this work: 1-Seasonally collect fish from Mediterranean-sea and studying the clinical picture in the examined fish. 2-Isolation and identification the pathogenic bacteria affecting Solea fish. 3-Registering the percentage of total and seasonal prevalence in such fish. 4-Make trials for diagnosis using recent techniques. 5-Application of biosafety in the lab. 6-Commitment of the basis and principles of scientific research ethics in all study stages. 7-Studying histopathological changes caused by these bacterial diseases from naturally infected fish. In the present study, a total of 120 Egyptian sole (Solea aegyptiaca) with various body weights (50-70 g) and lengths (13-19 cm) were collected seasonally and randomly from costal area of Mediterraneansea in Port Said Governorate, Egypt from September-2019 till August-2020. Moribund or freshly dead specimens collected in aerated airbags and/or iceboxes were transferred to Food Hygiene and Bacteriology Unit, Animal Health Research Institute, Port Said for further bacteriological, and molecular examinations in particular for Vibrio infection. Fish were found to be infected with Vibrio alginolyticus based on the characteristic phenotypic and biochemical profiles with a total prevalence of 29.16%. During the study, the highest incidence of vibriosis among the naturally infected sole fish was observed in the summer season (31.43%), with the prevalence in the spring and winter seasons being equal (25.72% each). In contrast, the lowest incidence of infection was observed during autumn (17.14%). Molecular investigation of pure isolates using specific set 184 Esraa Abdelazeem et al. of primers targeting the 16S rRNA conserved gene of Vibrio species gave expected amplicons size of 663 bp.

Prevalence, genetic diversity, and antimicrobial susceptibility of Vibrio spp. infected gilthead sea breams from coastal farms at Damietta, Egypt

“…In the present study, the obtained isolates were presumptively Vibrio spp. based on the morphological and biochemical identification, which were in full accordance with the standard reported in Bergey's manual of Systemic Bacteriology and matched to other studies [ 22 , 43 , 44 ]. As observed, juvenile fish (small-sized sea bream) demonstrated different prevalence of Vibrio infection, which is consistent with other studies reporting that small-sized fish with an ill-developed immune system have lower resistance to pathogens [ 45 – 47 ]; Another trail of studies reported that the incidence of Vibrio infection in farm-growing fish revealed the highest morbidity but a lower mortality rate [ 48 , 49 ].…”