Aquaculture International最新文献

The digital transformation of China’s traditional aquaculture industry has promoted the high-quality development of China’s aquaculture industry and helped China become one of the world’s largest aquaculture countries. In this paper, the current status of aquaculture digital transformation will be described from two perspectives: aquaculture process and aquaculture digital technology. The aquaculture process can be divided into eight steps by the eight-step intensive aquaculture method, and each aquaculture step and aquaculture digital intelligence technology are analyzed, revealing that technologies such as the Internet of Things (IoT), cloud computing, artificial intelligence, etc. promote high-speed growth of aquaculture productivity through the adjustment of aquaculture management decisions and the improvement of production factors, and that big data and blockchain technologies contribute to building a more trustworthy environment for online transactions and improving product traceability, offering potential steps toward integrated aquaculture. This review summarizes successful cases of digital transformation in Chinese aquaculture, providing a reference for the future development of digital aquaculture in the world. This review draws on the successful experience of China’s aquaculture transformation to help accelerate the adoption of digital intelligence in aquaculture plants around the world and to serve as a basis for the improvement of current and future digital intelligence technologies.

Accurately identifying fish feeding behavior in complex environments is crucial for optimizing feed management, improving feed utilization efficiency, and reducing aquaculture costs. Complex real-world environments, such as variations in water quality, lighting conditions, and background interference, make it difficult to distinguish feeding states. To address this issue, based on the fusion of attention mechanism-enhanced ResNet and an improved ConvNeXt (ResNet–MoVIT–ConvNeXt), a fish feeding intensity recognition method is proposed. A multi-scenario data augmentation method is designed to simulate complex fish feeding environments replicating real-world complex scenarios. The dual-branch model, combining ResNet and improved ConvNeXt, extracts local features from fish school images. The MobileViT module is then used for multi-level feature fusion, effectively capturing feeding behavior features for accurate feeding recognition. Finally, a multi-factor dynamic feeding strategy is provided, which combines fish biomass, water quality, and feeding states to reduce feed waste. This method introduces the MobileViT module into each stage of the ResNet and improved ConvNeXt networks. The proposed method is evaluated on real-world fish school datasets, achieving an overall accuracy of 99.19% and 98.5% for the medium state, surpassing existing comparative methods.

Microplastic (MP) contamination in aquaculture feed presents an increasing threat to both the aquaculture industry and global public health. This study examines the occurrence, abundance, characteristics, and risk assessment of MPs in commercial tilapia (Oreochromis niloticus) feeds. MP contamination was found in all feed samples, with the highest levels observed in grower feeds (2150 ± 70.71 MPs/kg), followed by starter feeds (1650 ± 70.71 MPs/kg) and finisher feeds (1300 ± 141.42 MPs/kg). Fibers were the dominant morphotype (85%), and polymer analysis using FTIR identified polypropylene (38.74%) and polyethylene (33.61%) as the most common polymers. Additionally, 84.64% of the extracted MPs were in the 100–1500 µm size range, posing significant health risks to tilapia and potential exposure to consumers. The estimated polymer hazard index (PHI) value for the three feed categories was very high, signaling alarming health risks. The mean polymer load index (PLI) values across the feed categories ranged from 4.23 to 8.03, indicating minor contamination. The study attributes the sources of MPs to feed ingredients, packaging materials, and processing machinery. The high PHI value underscores the need for urgent action to mitigate MP pollution in tilapia farming.

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The red seaweed Solieria filiformis is a source of nutrients, active biomolecules, and the iota(ι)-carrageenan hydrocolloid. In Brazil, it is found in natural stock; however, the sustainable biomass production of this seaweed species in the sea has not been reported. The S. filiformis cultivation was evaluated at Flecheiras Beach, on the coast of Ceara State in Northeast Brazil, using Long-line with Vertical Rope Structures (LVRS) and Colonized Modules (CM) methods during the rainy and dry seasons. The environmental parameters of the cultivation site, the daily growth rates (DGR) at 30, 45, and 60 days after planting, the biomass density, and the ι-carrageenan extracted were assessed. Local environmental conditions supported seaweed growth in both seasons. However, the highest DGR (6.1%) was recorded 30 days after planting during the dry season using LVRS. The highest seaweed biomass density was 53 kg ws module⁻¹ using CM method. The highest ι-carrageenan yields (48.3% and 53.1%) were obtained from the biomasses produced in the dry season, using LVRS and CM methods, respectively. The mean sulfate content of the ι-carrageenan extracted was 26.8 ± 1.9%, a relevant feature of their physicochemical properties and biological activities.

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The nursery phase in autumn is an important strategy for scaling up tilapia farming in subtropical regions, which otherwise suffers from a lack of fingerlings in winter. Tilapia nursery is carried out in a semi-intensive system in ponds; however, the biofloc technology system (BFT) has productive, environmental, and health advantages. This study aimed to compare the production of Nile tilapia (Oreochromis niloticus) juveniles in two rearing systems during autumn through the evaluation of fish growth performance, environmental, and hematological parameters, as well as production costs. The 46-day experiment was conducted on a pilot scale, with four experimental units per system stocked with fingerlings averaging 1.95 ± 0.32 g. In the semi-intensive system, 25 m³ ponds were used, and each was stocked with 1100 fingerlings (44 fish m⁻³). In the super-intensive system, 4 m³ circular tanks were used, each stocked with 2200 fingerlings (550 fish m⁻³). The production of tilapia juveniles in BFT showed greater stability of water quality parameters throughout rearing in association with higher water temperature owing to the greenhouse. This allowed similar growth between fish in both systems, but with productivity 12.7-fold higher in BFT, while consuming 29.6 times less water. Hematological parameters among fish in the two systems were also similar. Moreover, the BFT system demonstrated a 6.2% reduction in total operating costs compared to the semi-intensive pond system, positioning it as a more cost-effective option for producing Nile tilapia juveniles in subtropical regions. These results highlight the BFT system’s potential as a viable alternative for rural fish farmers.

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Quantum dots (QDs), a modern nanotechnology, have emerged as a transformative tool in aquaculture, enhancing efficiency and sustainability. This review highlights QD applications in detecting waterborne pathogens and pollutants through fluorescence, monitoring water quality parameters in real-time, targeted delivery of vaccines and therapeutics, and improving nutrition through nano-encapsulated feed supplements. QD’s unique optical properties enable sensitive and selective detection, while their small size facilitates cellular uptake and targeted delivery. Benefits of quantum dots in aquaculture include disease management, enhanced water quality, increased feed efficiency, and reduced environmental impact. Furthermore, recent applications of nano-inspired genes, nano-sensors, DNA-based nano-vaccines, and medication delivery systems have positively impacted fish health, immune systems, and reproduction. However, toxicity concerns and regulatory frameworks must be addressed. This comprehensive review provides an overview of QD applications in aquaculture, highlighting opportunities, challenges, and future research directions, ultimately contributing to a more sustainable and efficient aquaculture industry.

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The finfish aquaculture sector of Bangladesh plays a vital role in food security and the national economy. However, its sustainability is often jeopardized by disease outbreaks. This study evaluated disease management practices, biosecurity adoption status, and the factors influencing disease occurrence and biosecurity adoption in Bangladesh’s finfish aquaculture sector. Data were collected from 400 farmers across 6 major fish-producing districts through an online survey tool covering farmer demographics, fish culture practices, disease management practices, and adoption of biosecurity measures. Results revealed that most farmers were male (87%), experienced (> 10 years, 53%), literate, full-time (78%) operators, managing small-scale farms (< 0.45 ha), and favored polyculture technique. Disease occurrence ranked among the top two challenges, affecting approximately 70% of the studied farmers. Common disease management practices included water quality management and chemical therapeutics use (91% each), antibiotics use (53%), and other operational modifications. Overall, biosecurity adoption among farmers was approximately 68%, with 56% identified as high adopters. Widely adopted biosecurity practices included regular farm monitoring and having proper feed storage (96% each) while avoiding restocking (14%) was the least adopted. Significant (P < 0.05) regional variations were observed in farmer demographics, fish culture practices, disease occurrences, and biosecurity adoption levels. Significant associations between disease occurrence and biosecurity adoption with several socio-demographic and operational factors emphasized the need for tailored interventions. The findings thus underscore the importance of area-specific biosecurity guidelines and strategic approaches to enhance biosecurity compliance, reduce disease risks, and ensure the sustainability of the aquaculture sector.

The cytochrome P4503A (CYP3A) subfamily has been well characterized in vertebrates, where it plays a pivotal role in xenobiotic detoxification and the regulation of steroid hormone levels. However, their molecular features and functions in invertebrates remain poorly understood. The sea cucumber (Apostichopus japonicus) is not only a commercially significant mariculture species but also an excellent model for studying organ development and evolutionary biology. In this study, we identified seven CYP3A genes in A. japonicus using gonadal transcriptomic data. These genes exhibited ubiquitous expression across adult tissues, with significantly higher levels in ovarian tissues compared to testes tissues. Protein sequence analysis revealed that the catalytic residues Ala ₃₀₆-Thr ₃₁₀-Cys ₄₃₇, which are critical for aromatase activity, are highly conserved. This suggests that CYP3A proteins may mediate aromatization-like reactions similar to CYP19A in vertebrates. Additionally, dietary administration of the aromatase inhibitor letrozole led to histological changes in the testes and a reduction in the diameter of large oocytes in the ovaries. These findings provide valuable insights into the molecular mechanisms underlying gonadal development in sea cucumbers and lay the groundwork for future research on the artificial induction of sex reversal in echinoderms.