This study aimed to evaluate the efficiency of an integrated multi-trophic aquaculture (IMTA) system comprising co-cultured fed fish and organic extractive species representing three distinct trophic levels as well as the impact and potential utilization of two commercially available fish feeds made up of 35% fish meal (FM) and 20% fish meal (LFM) ingredients, using a multi-indicator assessment approach. Significant alterations were observed in growth performance indicators (GPIs), water and sediment quality indices, toxicity tests and biomarkers within the IMTA system. The fish survival, weight gain (WG), and specific growth rate (SGR) were higher in the IMTA system with significantly lower feed conversion ratios (FCRs) and higher feed efficiency (FE) in comparison to the fed fish monoculture system. Yet, organic filter feeders displayed 100% survival, and increased shell growth, while deposit feeders exhibited successful survival and significant weight gain. In the comparison between FM-IMTA and LFM-IMTA, fed fish in FM-IMTA showed higher WG, SGR, and FE with lower FCR. Environmental parameters like temperature, oxygen, and nutrient concentrations fluctuated but generally improved in the IMTA system, indicating lower mesotrophic conditions. Sediment fatty acid profiles differed between systems and toxicity assessments, which suggested a lower impact in IMTA and FM-IMTA systems. The sediment microbial community displayed high similarity within IMTA systems and between FM-IMTA and LFM-IMTA. These findings underscore the potential of IMTA systems for sustainable aquaculture, emphasizing improved growth performance and reduced environmental impact, particularly when using fish meal feeds.

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⁻¹ day⁻¹ for 7 days) to estimate pharmacokinetics and residue depletion, respectively. The maximum plasma concentration of FLO was measured to be 1.64 μg/ml, 4 hr post administration. The elimination half‐life (t_1/2b) and the area under the concentration‐time curve extrapolated to infinity (AUC_0‐∞) were calculated to be 13.0 hr and 34.7 μg h⁻¹ ml⁻¹, respectively. Withdrawal times of FLO and its amine were calculated to be 46.3 degree‐days, indicating a fast removal from the edible tissues of treated European seabass. Overall, FLO can be considered as a potentially efficient antibacterial agent for farmed European seabass provided that additional efforts will be devoted towards its in vitro and clinical efficacy.

Global warming remains a neglected environmental challenge for the sustainability of primary production, particularly aquaculture, which is highly susceptible to the spread of established pathogens and the induction of emerging infectious diseases under warming conditions. Over the past decade, Europe has experienced dramatically high temperatures that may impact both farmed fish and their pathogens in a largely unpredictable manner. While, in general, warming may boost the rate of disease transmission and its virulence by increasing pathogens' fitness in weakened hosts, some diseases characteristic of cooler environments may become rare. Field data is still largely fragmented, but in vitro experiments reveal that almost 28 microbial diseases in European finfish farming could be facilitated by climate warming. Innovative mitigation tools, such as fish selective breeding, epigenetic programming, the development of new vaccines, and alternative treatments, may prove essential in coping with the effects of rising water temperatures on fish diseases in Europe.

The aim of this study was to evaluate the efficacy of dietary praziquantel (PZQ), a promising fish anthelminthic, against Zeuxapta seriolae, a lethal ectoparasite of greater amberjack (Seriola dumerili Risso) farmed in the Mediterranean and elsewhere. The trial was carried out in small cages (3 m³) in situ, harbouring fish (125 ± 14 g) naturally infected with Z. seriolae, at 25 ± 1 °C water temperature. Praziquantel-medicated diet (150 mg PZQ/kg fish) was delivered for three days against a control group. Measurement of both adults and oncomiracidia of Z. seriolae in sampled gill arches revealed significant differences between the tested groups (PZQ: 19.3 ± 9.8 vs. Control: 3.8 ± 6.3). Considering an estimated efficacy of 80.4% in the medicated fish, the present study indicates that oral PZQ treatments can confront Z. seriolae infections considerably in farmed greater amberjack and, perhaps, replace the commonly used hydrogen peroxidase baths.

Active packaging with CO₂-emitters (pads) has recently been used for shelf-life extension of fresh fish. The aim of this study was to identify consumer attitudes towards fresh fish packaging, to examine whether Greek consumers prefer active packaging with pad over active packaging without pad, to investigate any perceived differences in the sensory freshness of the fish, and to relate consumer perception to volatile composition of fish fillets. In total, 274 consumers participated in the study which included freshness sensory evaluation of gilthead seabream (Sparus aurata) and seabass (Dicentrarchus labrax), whole-gutted and filleted, raw and cooked, at high quality and at the end of high-quality shelf-life. Samples were packed under modified atmosphere either with a pad or without. Results showed that consumers preferred packages with pads, especially at the end of high quality shelf-life. They perceived raw samples packed with a pad to be fresher and closer to the ideal product, and also had a higher purchase intention towards them. Cooked samples were not perceived differently. Consumers’ perception was in accordance with the GC-MS findings in the volatile compounds that function as freshness or spoilage indicators. Most participants were positive towards fresh fish packaging although they usually buy unpacked fresh fish. Our results suggest that active packaging with CO₂ emitters contribute to freshness preservation and that it has a positive potential in the Greek market.