Polyinfection in Fish Aeromoniasis: A Study of Co-Isolated Species in Outbreaks.

We studied the phenotypic and genomic characteristics related to the virulence and antibiotic resistance of two strains, which were co-isolated before an outbreak of among diseased seabass on Agathonisi Island, Greece, in April 2015. The first strain, AG2.13.

Perturbation of Quorum Sensing after the Acquisition of Bacteriophage Resistance Could Contribute to Novel Traits in .

Bacteria employ a wide range of molecular mechanisms to confer resistance to bacteriophages, and these mechanisms are continuously being discovered and characterized. However, there are instances where certain bacterial species, despite lacking these known mechanisms, can still develop bacteriophage resistance through intricate metabolic adaptation strategies, potentially involving mutations in transcriptional regulators or phage receptors. species have been particularly useful for studying the orchestrated metabolic responses of Gram-negative marine bacteria in various challenges.

Pathogenic and Opportunistic spp. Associated with Vibriosis Incidences in the Greek Aquaculture: The Role of as the Principal Cause of Vibriosis.

A monitoring program to follow vibriosis incidents in the Greek marine aquaculture was implemented over the past 13 years. 273 isolates, from various cases originating from eight regions and nine hosts, were collected and characterized. The main aquaculture species of the survey were the European seabass () and the gilthead seabream ().

Comprehensive Characterization of a Novel Bacteriophage, vB_VhaS_MAG7 against a Fish Pathogenic Strain of and Its In Vivo Efficacy in Phage Therapy Trials.

, a significant opportunistic marine pathogen, has been a challenge to the aquaculture industry, leading to severe economical and production losses. Phage therapy has been an auspicious approach in controlling such bacterial infections in the era of antimicrobial resistance. In this study, we isolated and fully characterized a novel strain-specific phage, vB_VhaS_MAG7, which infects MM46, and tested its efficacy as a therapeutic agent in challenged gilthead seabream larvae.

In planta interactions of a novel bacteriophage against Pseudomonas syringae pv. tomato.

The biology and biotechnology of bacteriophages have been extensively studied in recent years to explore new and environmentally friendly methods of controlling phytopathogenic bacteria. Pseudomonas syringae pv. tomato (Pst) is responsible for bacterial speck disease in tomato plants, leading to decreased yield.

Isolation and characterization of a novel species and a corresponding bacteriophage from a Mediterranean fish hatchery: Description of sp. nov. and Tenacibaculum phage Larrie.

sp. nov., a novel species of the genus was isolated from a commercial fish hatchery in Greece.

A fish kill at the Aposelemis dam (Crete, Greece) caused by heavy parasitism by Ichthyobodo sp.

A fish kill was recorded at the Aposelemis Dam, which is the main reservoir of drinking water for the island of Crete in Greece. Hundreds of goldfish were found dead at a side stream which provides water to the reservoir. The affected fish had been entrapped in a small pond at the side of the stream with practically zero water renewal as the event occurred in August which is a dry season for the island of Crete.

Vibrio Phage Artemius, a Novel Phage Infecting .

is an important pathogen of marine animals and has been the target of phage therapy applications in marine aquaculture for many years. Here, we report the isolation and partial characterization of a novel species of the family, the Vibrio phage Artemius. The novel phage was species-specific and could only infect strains of .

Genomic and Biological Profile of a Novel Bacteriophage, Vibrio phage Virtus, Which Improves Survival of Larvae Challenged with .

Due to the emergence of multidrug-resistant bacteria, commonly known as "superbugs", phage therapy for the control of bacterial diseases rose in popularity. In this context, the use of phages for the management of many important bacterial diseases in the aquaculture environment is auspicious. a well-known and serious bacterial pathogen, is responsible for many disease outbreaks in aquaculture, resulting in huge economic and production losses.

Expansion of the Beta-Proteobacterial Genus . Ichthyocystis: A Case Report of Epitheliocystis in the Pompano .

Epitheliocystis is a disease caused by a wide variety of host-specific intracellular bacteria infecting fish gills. In the Mediterranean Sea, epitheliocystis has been recently associated with a novel genus of beta-proteobacteria, the . Ichthyocystis genus.

Epitheliocystis in Greater Amberjack: Evidence of a Novel Causative Agent, Pathology, Immune Response and Epidemiological Findings.

Epitheliocystis is a fish gill disease caused by a broad range of intracellular bacteria infecting freshwater and marine fish worldwide. Here we report the occurrence and progression of epitheliocystis in greater amberjack reared in Crete (Greece). The disease appears to be caused mainly by a novel Betaproteobacteria belonging to the Ichthyocystis genus with a second agent genetically similar to Parilichlamydia carangidicola coinfecting the gills in some cases.

Development of autogenous vaccines for farmed European seabass against Aeromonas veronii using zebrafish as a model for efficacy assessment.

Aeromonas veronii bv. sobria is an emerging pathogen for the European seabass cultured in the Aegean Sea (Mediterranean) causing significant problems in the Greek and Turkish aquaculture industry since no licensed vaccine is currently available for the disease. A bivalent vaccine was developed based on two phenotypically distinct strains of the pathogen, PDB (motile, pigment-producing strain) and NS (non-motile, non-pigment-producing).

Comparative genomic analysis of dwarf Vibrio myoviruses defines a conserved gene cluster for successful phage infection.

Tailed bacteriophages have been at the center of attention, not only for their ability to infect and kill pathogenic bacteria but also due to their peculiar and intriguing complex contractile tail structure. Tailed bacteriophages with contractile tails are known to have a Myoviridae morphotype and are members of the order Caudovirales. Large bacteriophages with a genome larger than 150 kbp have been studied for their ability to use multiple infection and lysis strategies to replicate more efficiently.

Mediterranean Aquaculture in a Changing Climate: Temperature Effects on Pathogens and Diseases of Three Farmed Fish Species.

Climate change is expected to have a drastic effect on aquaculture worldwide. As we move forward with the agenda to increase and diversify aquaculture production, rising temperatures will have a progressively relevant impact on fish farming, linked to a multitude of issues associated with fish welfare. Temperature affects the physiology of both fish and pathogens, and has the potential to lead to significant increases in disease outbreaks within aquaculture systems, resulting in severe financial impacts.

Histological evaluation of sex differentiation and early sex identification in hatchery-produced greater amberjack (Seriola dumerili) reared in sea cages.

The histological process of gonadal differentiation, together with the endocrine changes of sex steroid hormones and some of their precursors, was studied in hatchery-produced greater amberjack Seriola dumerili from 101 until 408 days post-hatching (dph), with samplings conducted every 50 days. Histological processing showed that sex differentiation began at 101 dph with the formation of the ovarian cavity in females, while the presumptive males did not yet contain any germ cells in their gonad. At 150 dph, we observed the first germ cells in the developing testes.

Antibacterial Effects of Essential Oils of Seven Medicinal-Aromatic Plants Against the Fish Pathogen bv. : To Blend or Not to Blend?

Despite progress achieved, there is limited available information about the antibacterial activity of constituents of essential oils (EOs) from different medicinal-aromatic plants (MAPs) against fish pathogens and the complex interactions of blended EOs thereof. The present study aimed to investigate possible synergistic antimicrobial effects of EOs from seven Greek MAPs with strong potential against bv. a fish pathogen associated with aquaculture disease outbreaks.

The Development of Bacteriophage Resistance in Depends on a Complex Metabolic Adaptation Strategy.

Lytic bacteriophages have been well documented to play a pivotal role in microbial ecology due to their complex interactions with bacterial species, especially in aquatic habitats. Although the use of phages as antimicrobial agents, known as phage therapy, in the aquatic environment has been increasing, recent research has revealed drawbacks due to the development of phage-resistant strains among Gram-negative species. Acquired phage resistance in marine has been proven to be a very complicated process utilizing biochemical, metabolic, and molecular adaptation strategies.

Evaluation of absorption and depletion of florfenicol in European seabass Dicentrarchus labrax.

The pharmacokinetic properties and residue elimination of florfenicol (FLO) and its amine were investigated in European seabass Dicentrarchus labrax at 24°C. The trial mainly included analysis of FLO in plasma after a single dose dietary administration of 10 mg/kg and in muscle plus skin following a multiple dosing (10 mg kg  day for 7 days) to estimate pharmacokinetics and residue depletion, respectively. The maximum plasma concentration of FLO was measured to be 1.

Biological and Genomic Characterization of a Novel Jumbo Bacteriophage, vB_VhaM_pir03 with Broad Host Lytic Activity against .

is a Gram-negative marine bacterium that causes major disease outbreaks and economic losses in aquaculture. Phage therapy has been considered as a potential alternative to antibiotics however, candidate bacteriophages require comprehensive characterization for a safe and practical phage therapy. In this work, a lytic novel jumbo bacteriophage, vB_VhaM_pir03 belonging to the family was isolated and characterized against type strain DSM19623.

Complete Genome Sequence of a Jumbo Bacteriophage, vB_pir03, against Vibrio harveyi.

is a persistent pathogen responsible for disease outbreaks in aquaculture. We have sequenced the genome of a jumbo phage, vB_pir03, isolated in Greece. Here, we present the complete genome of vB_pir03, which consists of 286,284 bp and 336 open reading frames.

Host-Parasite Interaction between Parasitic Cymothoid and Its Host, Farmed European Sea Bass ().

Parasitic isopod (Cymothoidea, Isopoda) is a common and generalist buccal cavity-dweller in marine fish, recognised for its detrimental effect in fingerling and juvenile farmed European sea bass (). Although distributed throughout the Mediterranean, the isopod provokes acute outbreaks mainly limited to particular endemic areas in Croatia (Adriatic Sea) and Greece (Aegean Sea). While numerous studies have previously evidenced its gross effect on farmed fish (i.

Comparative Evaluation of Essential Oils from Medicinal-Aromatic Plants of Greece: Chemical Composition, Antioxidant Capacity and Antimicrobial Activity against Bacterial Fish Pathogens.

The administration of antibiotics in aquaculture has raised concern about the impact of their overuse in marine ecosystems, seafood safety and consumers' health. This "green consumerism" has forced researchers to find new alternatives against fish pathogens. The present study focused on 12 Mediterranean medicinal-aromatic plants as potential antimicrobials and antioxidant agents that could be used in fish aquaculture.