Characterization of Vibrio Populations from Cultured European Seabass and the Surrounding Marine Environment with Emphasis on V. anguillarum

Abstract

Vibrio species are widely distributed and can be potentially pathogenic to aquatic organisms. In this study, we isolated Vibrio spp. from environmental samples (seawater, sediment, and fish swabs) collected over a three-year period from a fish farm in Mali Ston Bay in the Adriatic Sea, Croatia, and assess their distribution. A total of 48 seawater samples and 12 sediment samples, as well as gill and skin swabs from 110 farmed European seabass, were analysed for the presence of Vibrio. Vibrio strains were identified to the species level by MALDI TOF MS. The analysis revealed that V. alginolyticus was the predominant species in European seabass, followed by V. anguillarum. V. alginolyticus was isolated from the sediments, along with V. gigantis and V. pomeroyi, while V. chagasii, V. cyclitrophicus, V. fortis, V. gigantis, V. harveyi, V. pelagius, and V. pomeroyi were isolated from seawater. V. anguillarum was isolated only twice during two different spring seasons, once from a diseased sea bass and the second time from a healthy sea bass. We analysed these two isolates and found that they differ both genetically and in terms of resistance to antibiotics. Our results confirm the seasonality of vibriosis incidence and the presence of the pathogenic V. anguillarum, which increases the risk of vibriosis.

Adriatic Sea Fishery Product Safety, Prospective and Climate Change

“…The results of the study confirm the seasonal nature of vibriosis incidence and the presence of pathogenic V. anguillarum, which heightens the risk of vibriosis [65]. Also, the cultivable microbiota linked to plastic debris gathered by commercial fishing trawlers in the south-eastern Adriatic Sea was object of a study conducted by Kapetanovića et al [65]. The prevalence of Vibrio was notably higher on plastic debris compared to the adjacent seawater and sediment.…”

“…Upon analysis, these two isolates were found to differ genetically and in terms of antibiotic resistance. The results of the study confirm the seasonal nature of vibriosis incidence and the presence of pathogenic V. anguillarum, which heightens the risk of vibriosis [65]. Also, the cultivable microbiota linked to plastic debris gathered by commercial fishing trawlers in the south-eastern Adriatic Sea was object of a study conducted by Kapetanovića et al [65].…”

Partial Characterization of Three Bacteriophages Isolated from Aquaculture Hatchery Water and Their Potential in the Biocontrol of Vibrio spp.

“…These species are already frequently isolated during vibriosis outbreaks [49,50]. Vibrio harveyi is frequently found in shrimp cultures, whereas Vibrio anguillarum is commonly associated with disease in sea bass and trout [51][52][53]. Studies suggest that Vibrio scophthalmi is an opportunistic pathogen that typically does not cause disease in healthy fish.…”

Microbial Communities in Changing Aquatic Environments

“…These are, for example, temperature, salinity, pH, dissolved oxygen concentration, availability of nutrients, organic matter, light, and pressure [4,9]. Particular attention is paid to opportunistic pathogens such as Vibrio [10,11], Legionella [12], Listeria [13], etc., which can multiply in altering surroundings and develop multiple resistances. Due to the weakening of immunity in the population, more and more people are affected.…”