Reviews in Aquaculture最新文献

Studies have demonstrated adverse effects of global warming on aquatic ecosystems. However, the effects of increased water temperature (IWT) on fish reproduction are still doubtful in species spawning at low or high temperatures. In this meta-analysis, we elucidated the effects of global warming on spermatozoa functions, key determinants of male fertility. We recruited 245 data records from 20 studies spanning 20 cold- and warm-water fishes to identify the effects of IWT on sperm quality. Data were re-processed and re-analyzed to determine the overall effects of IWT on sperm kinetics such as percentage of motile spermatozoa (MOT), duration of spermatozoa motility (DSM), curvilinear velocity (VCL), straight line velocity (VSL), average path velocity (VAP), as well as on enzymatic activities for energy supply (EAES) and antioxidant enzyme activity (ANEA). The standardized mean difference was calculated for each study, with positive values indicating higher performance under IWT. Results showed that (a) the overall effect size for MOT was larger negative in cold-water fishes (−1.22) than in warm-water fishes (−0.95). (b) Each 1°C increase in the activation medium reduced MOT by 1.30% (cold-water fishes) and 3.47% (warm-water fishes). (c) IWT negatively affected DSM, decreasing it by 10 s (cold-water species) and 5.64 s (warm-water species) per degree of IWT. (d) Spermatozoa velocity (VCL and VSL) increased by IWT in warm-water species. (e) In cold-water species, IWT-induced detrimental effects on EAES were associated with adverse impacts on sperm motility kinetics. In conclusion, IWT negatively affects sperm motility kinetics, suggesting an impact of global warming on fish reproduction.

The expansion of aquaculture production into more exposed harsh and remote ocean environments presents both new opportunities and challenges. To manage the complexities of exposed operations, research into fish welfare, personnel safety, and facilitating technology is thus of key importance. This paper reviews recent research advances in the areas of safety, fish welfare, and technology, while the focus is on the Norwegian salmon farming industry, the results could benefit exposed fish farming internationally. Regarding fish welfare, the study summarizes the current knowledge status of salmon coping abilities and welfare indicators in strong currents and waves. On the safety front, there has been significant progress in operational safety management, accident analysis, and emergency preparedness, all of which are crucial for human personnel in these demanding settings. Human safety and fish welfare also rely on structures and equipment, and recent research results include advances in environmental load analysis, vessel design, simulations of fish farms. Notably, the development of contact-free, autonomous lifting operations, and hole detection methods represents a significant leap in maintaining aquaculture infrastructure. This multidisciplinary study underscores the need for integrated research approaches to address exposed aquaculture, emphasizing that while recent innovations have enhanced safety and robustness, ongoing research and new strategies are critical for safety and fish welfare in exposed aquaculture operations.

In 2017, a new regulatory management system, the traffic light system (TLS), was implemented to estimate the effects of salmon lice from Norwegian salmon aquaculture on marine survival of wild Atlantic salmon and forms the basis of aquaculture capacity regulation. The TLS relies on observational data and a set of models to estimate the risk for negative impact on wild salmon populations. This review of the literature that forms the basis for the TLS as well as other relevant studies is presented in the context of the currently practiced TLS and suggestions are made for immediate and long-term improvements. The main findings of this review are that: (1) assumed timing and duration of smolt migration contribute to unreliable observational and modelled data and overestimates of infection pressure; (2) production of lice larvae from farmed salmon is overestimated; (3) TLS model systems rely on or are calibrated by the same potentially flawed data; (4) lice-associated mortality in wild salmon smolts may be overestimated; and (5) lice infection levels on farms are not associated with measurable effects on wild salmon. Recommendations to improve the accuracy and reliability of the TLS, and hence its environmental efficiency include the more complete use of available biological and physical environmental variables, adjusting the time period that observational data are registered and modelled data are integrated, adjusting the interpretation of data including recognition of uncertainty in model outcomes, and use of more realistic assumptions concerning lice-induced mortality thresholds.

Bivalve farming was usually considered as a CO₂ source through respiration and calcification, but recent studies suggest its potential as a CO₂ sink, prompting exploration of its inclusion in carbon markets. Here we reviewed the scientific basis behind this idea and found that it is not supported by observational and experimental studies. This idea indeed arises from carbon budget models that are based on theoretical misconceptions regarding seawater carbonate chemistry. The main misunderstanding consists of assuming that the carbon trapped in the shell originates from atmospheric CO₂ when it mostly comes from (bi)carbonate ions. While these ions originate from atmospheric CO₂ through the erosion of minerals over geological time scales, their incorporation into shells does not prompt short-term CO₂ compensation. The opposite occurs—calcification releases CO₂ in seawater and limits or even prevents the uptake of atmospheric CO₂. Some authors suggest that considering the bivalve farm ecosystem could change the perspective on the source/sink issue but there is no evidence for that now. Most ecosystem-based carbon budget models rely on several unverified assumptions and estimates. Although challenging, field measurements must be conducted for monitoring, reporting, and verifying atmospheric CO₂ uptake before qualifying for carbon credits. To achieve scientific consensus, we need reinforcing measurement-based studies of CO₂ fluxes in shellfish ecosystems, integrating carbon balance models with observational and experimental science, and fostering interdisciplinary collaboration. Although bivalve farming provides numerous environmental benefits and is vital for sustainable aquaculture, there is currently no evidence that it contributes to CO₂ capture.

The trade in live ornamental fishes to be held as companion animals or displayed in public aquaria has an estimated global annual value of US$15–20 billion. Supply chains for ornamental pet fishes often involve many more parties than for fish farmed as food fishes, and at each stage, fishes are exposed to stressors including handling, confinement, crowding, mechanical disturbance, and poor water quality. If chronic, these stressors can compromise their immune system, making fishes more susceptible to pathogens. Mortality and morbidity from infectious disease can result in considerable welfare impacts and massive economic losses for the industry, and the range of infective agents seen in ornamental species is well documented. However, treating these diseases is not straightforward with practices varying greatly across the trade and with several approaches having unintended consequences, such as the emergence of resistant strains of pathogens. While disease treatments for a handful of fish species (e.g., koi, goldfish) have received focused research attention, for the home aquarium owner, there is an increasing reliance on products based on natural compounds which have received far less scientific attention. This review aims to highlight the gaps in our knowledge surrounding the range of disease treatments used across the ornamental pet fish trade, with a particular focus on freshwater tropical species destined for home aquaria. Consideration is given to the potential problems arising from these treatments, including microbial resistance and effects of treatments themselves on fish health and welfare.

A literature search approach (using Scopus®, Elsevier© database) was established to identify peer-reviewed articles published in English between 1960 and 2023 dealing with ‘sustainable aquaculture’ and focusing on specific aquaculture practices (aquaponics, integrated multi-trophic aquaculture, biofloc and recirculating aquaculture systems). Text Mining combined with Topic Analysis was utilized to extract information from the text data of the papers identified. After an appropriate screening procedure, 1111 articles were selected. The analysis showed a gradual increase in sustainable aquaculture publications over time, peaking at more than 200 publications in 2023. The first articles on biofloc, integrated multi-trophic aquaculture and recirculating aquaculture systems as alternative aquaculture practices began to appear in 2010, while studies in aquaponics have only been published since 2015. Most publications (40%) came from Asia, in line with the leadership of this continent in aquaculture. European also showed considerable interest in sustainable aquaculture practices, with Italy (leader in publications), Portugal and Germany researchers contributing with 111 papers on the subject in the past 30 years. This study identified the main research topics on the subject and observed how these have evolved. The papers analysed dealt mainly with optimization of aquatic life, genetic in aquaculture and disease management. The topic of protein replacement in feed was also important, with the term ‘diet’ the most frequently utilized in papers. The subjects identified could serve as valuable primary data source, offering opportunities for deeper examination, such as systematic reviews on research topics or geographic regions.