Sturgeon farming poses an interesting decision: give priority to highly prized caviar or meat. Indeed, sturgeons are mainly reared in aquaculture to produce caviar. However, the economic profitability of a sturgeon farm also depends on the existence of a meat market. Meat is still an important product for sturgeon farmers once the stock of caviar-producing females has been established. This paper takes a case study approach and analyses how an Italian producer addresses the trade-off, adopting a methodology that measures the value of the economic productivity of production inputs, e.g., the measure of the profitability of the inputs, and compares them with the costs of the inputs and the prices of the outputs. This analysis is the first attempt, to our knowledge, to adopt an economic analysis to address this choice problem, based on a very representative case study. This helps monitor whether the farm’s production choices are economically efficient and effective and whether and how those can be improved. The results show that the farm maximizes profit but does not reach its optimal production level. This implies that both (1) producing more output and (2) a further switch to caviar production for less meat are economically efficient production strategies.

Aquaculture is a globally widespread practice and the world’s fastest-growing food sector and requires technological advances to both increase productivity and minimize environmental impacts. Monitoring the sector is one of the priorities of state governments, international organizations, such as the Food and Agriculture Organization of the United States (FAO), and the European Commission. Data collection in aquaculture, particularly information on the location, number, and size of production facilities, is challenging due to the time required, the extent of the area to be monitored, the frequent changes in farming infrastructures and licenses, and the lack of automated tools. Such information is usually obtained through direct communications (e.g., phone calls and e-mails) with aquaculture producers and is rarely confirmed with on-site measurements. This study describes an innovative and automated method to obtain data on the number and placement of structures for marine and freshwater finfish farming through a YOLOv4 model trained on high-resolution images. High-resolution images were extracted from Google Maps to test their use with the YOLO model for the identification and geolocation of both land (raceways used in salmonids farming) and sea-based (floating sea cages used in seabream, seabass, and meagre farming) aquaculture systems in Italy. An overall accuracy of approximately 85% of correct object recognition of the target class was achieved. Model accuracy was tested with a dataset that includes images from Tuscany (Italy), where all these farm typologies are represented. The results demonstrate that the approach proposed can identify, characterize, and geolocate sea- and land-based aquaculture structures without performing any post-processing procedure, by directly applying customized deep learning and artificial intelligence algorithms.

Between 2014 and 2023, Italian Manila clam (Ruditapes philippinarum) production declined by 36% due to climate change and predation by the invasive blue crab (Callinectes sapidus), which preys particularly on small clams. Traditionally, Manila clam farming starts with seed collection from natural recruitment or hatcheries, followed by pre-fattening in raceways and/or FLUPSY (Floating Upweller Systems) to size T3 (>3 mm). The fattening phase in lagoons up to the commercial size (>25 mm) follows. Rearing juveniles in controlled conditions may ensure stable supplies of high-quality seed, reduced mortality, and increase overall yields. Furthermore, a larger pre-seeding size (e.g., T10, >10 mm) is supposed to improve resistance to predators and environmental stress. This study uses an ex-ante Life Cycle Assessment (LCA) to evaluate the potential environmental impacts of a novel and unique “sand-nursery” method under development at an Italian company. The nutrient removal potential of juvenile clams was also assessed as an ecosystem service. At full capacity, the optimised system could produce 120 t of liveweight juveniles and remove 338 kg of nitrogen and 32 kg of phosphorus. Although it has inherent limitations, the ex-ante LCA results show that electricity consumption is the main contributor to environmental impacts, with a global warming potential of 1.11 kg CO₂ eq/kg T10 clam. Further research is needed to assess impacts across the full production cycle.

Phagocytosis in vitro assays are widely used to assess the health status of fish, since it may be affected by diseases and environmental factors. To date, studies have evaluated phagocytosis in fish by observing fluorescent beads or bacteria engulfed by phagocytes. However, particles adhering to the external surface of the phagocyte membrane cannot be easily distinguished from those that are truly internalized. This work aimed to: (1) test whether a pHrodo™ (pHR)-based method improves the accuracy of phagocytosis detection compared to traditional assays; (2) evaluate the influence of opsonization, incubation time, and temperature on the phagocytosis ability of rainbow trout (Oncorhynchus mykiss) peripheral blood leukocytes (PBLs). Opsonization increased the PBLs’ phagocytic activity. To evaluate the effects of incubation time and temperature on PBL phagocytosis ability, 30% autologous plasma was used. Leukocytes incubated at 16 °C for 2 h showed a significantly higher (p < 0.05; H = 45.43) percentage of phagocytic cells. This incubation setting also resulted in increased pHR-related fluorescence intensity (p < 0.05; F = 58.39), directly proportional to the number of phagocytosed particles. These findings indicate that opsonization enhances phagocytic ability and capacity, and that a 2 h incubation at 16 °C may be recommended for future large-scale studies aimed at evaluating innate immune function in rainbow trout.

Sea cucumbers, important members of the phylum Echinodermata, play a crucial role in sediment mixing and nutrient cycling on the seafloor. They also hold significant economic value, particularly in Asian food and pharmaceutical markets. In the Mediterranean Sea, the harvesting of sea cucumbers has recently intensified, often without regulation, threatening both species populations and the health of benthic ecosystems. This study investigated the potential of using fatty acid (FA) profiles as ecological biomarkers to trace the different origin and feeding ecology of two sea cucumber species, Holothuria polii and H. tubulosa, collected from ten coastal sites in Italy. A total of 285 individuals were analyzed through lipid extraction and characterization from their body walls using gas chromatography (GC-FID and GC-MS). Key fatty acids identified included arachidonic acid, eicosapentaenoic acid, eicosenoic acid, palmitic acid, palmitoleic acid, stearic acid, and nervonic acid. Principal Component Analysis (PCA) revealed patterns consistent with geographic origin, suggesting that FA profiles can reflect site-specific trophic conditions. The analysis also indicated that sea cucumbers primarily feed on diatoms, bacteria, and blue-green algae, with notable regional variation. This study is the first to successfully apply FA-based trophic markers to differentiate Italian populations of these species, providing insights for ecological monitoring and fishery management.