Vibriosis as an epizootic disease of rainbow trout (Onchorynchus mykiss) in Turkey

Genome-wide characterization of integrin (ITG) gene family and their expression profiling in half-smooth tongue sole (Cynoglossus semilaevis) upon Vibrio anguillarum infection

Integrins (ITGs) are transmembrane heterodimer receptors with ITGα subunit and ITGβ subunit, participating in various physiological processes, including immunity. At present, systematic research on ITGs in teleost is scarce, especially in half-smooth tongue sole (Cynoglossus semilaevis). In this study, a set of 28 ITG genes in half-smooth tongue sole have been identified and characterized. The phylogenetic analysis showed that ITGα and ITGβ subunits were respectively classified into five and two clusters, consistent with previous studies. The selection pressure analysis indicated that most of ITG genes were under purifying selection, except for ITGα11b and ITGαL with positive selection. The expression profiles of eight selected ITG genes, including ITGα1, ITGα5, ITGα8, ITGα11, ITGβ1, ITGβ2, ITGβ3, and ITGβ8, were analyzed in healthy tissues and after infection with Vibrio anguillarum, revealed their implications in immune response. The study provided a comprehensive characterization and expression analysis of ITG genes in half-smooth tongue sole, setting a solid foundation for further functional studies and promising potential in disease control.

Detection and Antimicrobial Resistance of Vibrio Isolates in Aquaculture Environments: Implications for Public Health

The aim of this study was to evaluate the presence of Vibrio isolates recovered from four different fish pond facilities in Benin City, Nigeria, determine their antibiogram profiles, and evaluate the public health implications of these findings. Fish pond water samples were collected from four sampling sites between March and September 2014. A total of 56 samples were collected and screened for the isolation of Vibrio species using standard culture-based methods. Polymerase chain reaction (PCR) was used to confirm the identities of the Vibrio species using the genus-specific and species-specific primers. Vibrio species were detected at all the study sites at a concentration on the order of 10(3) and 10(6) CFU/100 ml. A total of 550 presumptive Vibrio isolates were subjected to PCR confirmation. Of these isolates, 334 isolates tested positive, giving an overall Vibrio prevalence rate of 60.7%. The speciation of the 334 Vibrio isolates from fish ponds yielded 32.63% Vibrio fluvialis, 20.65% Vibrio parahaemolyticus, 18.26% Vibrio vulnificus, and 28.44% other Vibrio species. In all, 167 confirmed Vibrio isolates were selected from a pool of 334 confirmed Vibrio isolates for antibiogram profiling. The susceptibility profiles of 20 antimicrobial agents on the isolates revealed a high level of resistance for AMP(R), ERY(R), NAL(R), SUL(R), TMP(R), SXT(R), TET(R), OTC(R), and CHL(R). The percentage of multiple drug resistance Vibrio isolates was 67.6%. The multiple antibiotic resistance index mean value of 0.365 for the Vibrio isolates found in this study indicated that the Vibrio isolates were exposed to high-risk sources of contamination when antibiotics were frequently used. The resistant Vibrio strains could be transmitted through the food chain to humans and therefore constitutes a risk to public health.

Status and future perspectives of vaccines for industrialised fin-fish farming

Fin fish farming is developing from extensive to intensive high industrial scale production. Production of fish in high-density growth conditions requires effective vaccines in order to control persistent and emerging diseases. Vaccines can also have significant positive impact on the reduced usage of antibiotics. This was demonstrated when vaccines were introduced in Norway for Atlantic salmon (Salmo salar) in the late eighties and early nineties, resulting in a rapid decline of antibiotics consumption. The present review will focus on current vaccine applications for farmed industrialized fish species such as Atlantic salmon, coho salmon (Oncorhynchus kisutch), rainbow trout (Oncorhynchus mykiss), ayu (Plecoglossus altivelis), cod (Gadus morhua), sea bass (Dicentrarchus labrax), gilt-head sea bream (Sparus aurata), yellowtail (Seriola quinqueradiata), great amberjack (Seriola dumerili), barramundi (Lates calcarifer), japanese flounder (Paralichythys olivaceus), turbot (Scophthalmus maximus), red sea bream (Pagrus major), rock bream (Oplegnathus fasciatus), seven band grouper (Epinephelus septemfasciatus), striped catfish (Pangasianodon hypophthalmus), channel catfish (Ictalurus punctatus) and tilapia (Oreochromis niloticus). This paper will review the current use of licensed vaccines in fin fish farming and describe vaccine administration regimes including immersion, oral and injection vaccination. Future trends for inactivated-, live attenuated - and DNA - vaccines will also be discussed.