Journal of The World Aquaculture Society最新文献

This study evaluates the growth, proximate, and fatty acid composition of black mussel, Mytilus galloprovincialis fed four marine microalgae (Pavlova lutheri, Nannochloropsis oculata, Diacronema vlkianum and Rhinomonas reticulata) diets for 21 days. Black mussel is a common bivalve species that has been recognized as important for marine aquaculture with increasing production in the last two decades. The mussel group fed N. oculata showed a significantly lower survival rate than the other groups (p < 0.05). Shell height, length, and width of mussels were measured. The height and length of the mussel group fed N. oculata were statistically higher than other experimental groups (p < 0.05). Shell width did not show any significant differences among groups (p > 0.05). The microalgae N. oculata showed the highest protein content whereas P. lutheri had the highest crude lipid content among dietary treatments. The group fed P. lutheri showed significantly higher protein, lipid, and ash contents among experimental groups (p < 0.05). The D. vlkianum diet enhanced the highest docosahexaenoic acid level in black mussels. Black mussel fed P. lutheri showed the highest eicosapentaenoic acid and polyunsaturated fatty acid levels. Arachidonic acid was found to be similar among experimental groups. In our study, P. lutheri and D. vlkianum had outstanding results on survival, growth, and essential fatty acid accumulation in mussel culture.

The Chinese mitten crab (Eriocheir sinensis) is bred extensively in Eastern and Northern China and faces a series of problems such as frequent diseases, germplasm degradation, and declining benefits, which have appeared to seriously affect the sustainable development of the cultivation industry. Haematococcus pluvialis, a type of unicellular green algae, have been proven to be the suitable dietary supplementation in crustacean feeds. After 14 days of feeding with 5% dietary supplementation with Haematococcus pluvialis powder, the growth, antioxidantase activities, and gut microbiota of E. sinensis were analyzed. The results indicated that H. pluvialis powder could significantly improve growth indicators including weight gain rate (WGR) and specific growth rate (SGR) of E. sinensis (p < 0.05). The levels of superoxide dismutase (SOD) and catalase (CAT) declined, while that of phenoloxidase (PO) kept rising under the treatment of H. pluvialis powder. Moreover, alkaline phosphatase (AKP) activity dropped initially and then increased. No significant differences in the Simpson index and Chao1 index in the control and H. pluvialis powder treatment were observed (p > 0.05). Although the dominant microbiota in the crab gut were not affected significantly by H. pluvialis powder, significant differences in the relative abundance of the dominant phyla between the control and H. pluvialis powder treatment groups were observed (p < 0.05). Furthermore, the relative abundance of Firmicutes and Candidatus_Bacilloplasma, which play an important role in the life activities of E. sinensis, were significantly higher in the group treated by H. pluvialis powder than in the control (p < 0.05). Therefore, the H. pluvialis powder could be potentially used not only as a rapid fattening regulator, but also to improve the immunity and metabolic capacity of E. sinensis.

Aquaculture recirculation technology has evolved in recent years, as it can save water use and maintain good water quality during tiger shrimp fry rearing and ultimately increase juvenile production. The recirculation technology in this experiment is expected to be adopted by small-scale tiger shrimp seed farmers. This study aims to develop the technology for producing a juvenile tiger shrimp recirculation system to support shrimp cultivation in ponds. The recirculation system container comprises a biofiltration tank filled with oysters, seaweed, and tilapia. Containers to keep tiger shrimp larvae alive in the recirculation system use a round-shaped container with a volume of 2 m³. Tiger shrimp larvae were cared for at; A. density of 2000 individuals/m²; B. density of 1500 individuals/m²; and C. density of 1000 individuals/m². This study found that the survival rate of tiger shrimp in treatments C and B were high, reaching 96.800^b ± 2.716% and 91.62^b ± 3.432%, respectively, while survival in treatment A was the lowest, at 81.700^a ± 4.715%.

Feed conversion ratio (FCR) is widely used as a measure of feed use efficiency in commercial aquaculture production and research. Surprisingly, little work has focused on the factors that affect FCR in plankton-based, commercial ponds despite the widespread use of FCR as a production metric. Proposals to use FCR as a numeric standard for environmental regulation (mandatory or voluntary) raise questions as to whether FCR meets the reliability and consistency requirements of a good metric, and whether it would lead to desired behavioral changes. This article summarizes FCR data from university research verification programs conducted on US catfish farms and databases developed from commercial farm records. The relevant research literature is synthesized with respect to factors that affect FCR. US catfish is used as a case study because pond-level data from verification trials (Extension/research-led on-farm trials of best available science) and commercial farm records are available. While specific to US catfish production, the analysis provides insights into factors affecting FCR that likely apply to other pond-based aquaculture species. Commercial verification of pond data showed (1) significant variation in FCR (coefficients of variation from 1% to 47%) among ponds with similar stocking, feeding, and aeration rates; (2) significant effects of survival on FCR; and (3) no significant effects on FCR of yield, feed type, management, or production system. Improvements in FCR would occur with improved survival that requires improved management of federally protected fish-eating bird populations and development of additional, effective vaccines for diseases. FCRs were found to not exhibit the degree of reliability and consistency required for use as an effective metric or numeric standard for regulatory purposes. Use of FCR for mandatory or voluntary regulation is unlikely to lead to behavioral changes by farmers.

This study focuses on the structural integrity analyses of a submersible cage with dimensions of 20 m in diameter and 10 m depth under extreme oceanographic conditions, including current speed of 0.5 and 1 m/s, combined with waves ranging from 2 to 5 m in height and a period of 7 s. Employing a dynamic simulation model based on finite elements, The study examines the stresses in the cage's pipes, as well as the tension in the bridle lines and mooring lines. Results indicate that submerging the cage leads to a reduction in peak tensions, with mooring lines experiencing a decrease of up to 32% and bridle lines experiencing a decrease of up to 59%. Furthermore, the stresses in the pipes exhibit a significant decline of up to 71.4%. These findings demonstrate that the submersible cage, when submerged, significantly reduces peak stresses, thereby decreasing the risk of structural loss or damage when the system is submerged.

In this study, the impact of adding 10% or 20% torula yeast (PB TY10 and PB TY20) to a fishmeal-free diet on digestibility and growth of juvenile rainbow trout was assessed. The yeast diets were compared with a plant-only diet (PB) and a diet containing 20% fishmeal (FM). The apparent digestibility of dry matter, protein, energy, and ash of yeast in trout (~120 g) were 78.6%, 93.8%, 84.8%, and 48.7%, respectively. All PB diets had higher protein digestibility and PB TY20 had higher ash digestibility than the FM diet. To assess growth, trout (~44 g) were divided into triplicate tanks (30 per tank) and fed one of the four experimental diets for 12 weeks. The PB diet resulted in lower growth and daily feed intake (p < 0.05), but adding yeast significantly improved them. Final weight of PB TY10 did not differ significantly from that of FM. Expression of oclna and cldn15 in the proximal intestine increased in trout fed yeast (p < 0.05). Expression of tlr2, mcsfr, and tnfa, as well as the plasma lysozyme concentration, increased with PB TY20 (p < 0.05). In conclusion, torula yeast has the potential to improve the robustness and growth of rainbow trout in the context of fishmeal-free diets.

Aquaculture is now the main source of seafood in human diets and is one of its fastest-growing industries worldwide. However, the industry is facing several difficulties, including infectious diseases, the most significant limiting factor for aquaculture expansion. The impact of diseases on aquaculture growth, fecundity, mortality rates, and marketability is profound. Hence, the ability to predict disease outbreaks is crucial to overcoming these challenges. Various infectious agents such as bacteria, viruses, fungi, and parasites can cause significant losses of fish in intensive aquaculture practices. In an aquaculture environment, the high host density coupled with restricted water flow promotes pathogen spread. Early detection of disease is crucial for farmers as mortality rates can reach as high as 100% if left untreated. Therefore, new techniques and technical solutions for disease management in aquaculture are required. In this context, data analytics technologies, such as internet of things (IoT) sensors, artificial intelligence, and machine learning, allow farmers to proactively monitor their farms and detect potential disease outbreaks before they strike. Here, we highlighted the potential of machine learning algorithms in early pathogen detection and the possibilities of intelligent aquaculture in controlling disease outbreaks at the farm level. IoT is currently a popular study topic for smarter and sustainable aquaculture, as seen by the growing interest and broad overall assumptions. Therefore, this review aims to provide comprehensive information on the various aspects and challenges associated with modern technologies for controlling pathogenic microorganisms, as well as the potential benefits of using the IoT to improve fish health and welfare in aquaculture.

This trial was performed in order to investigate the response of zebrafish (Danio rerio) to dietary exposure to polystyrene nanoplastics (PS-NPs) under laboratory conditions on fish growth and health. Healthy zebrafish (n=240) were divided into 12 tanks and fed with diets including 0 (T0), 100 (T1), 500 (T2), and 1000 (T3) mg kg⁻¹ synthesized polystyrenes nanoplastics (PS-NPs) for 30 days. At the end of trial, fish fed the PS-NPs supplementation showed weight gain percentages of 79.45%, 70.35%, and 61.88% for T1, T2, and T3 groups, respectively, compared with 87.39% in the control fish. The SOD, GPX and MDA activities and cortisol levels increased by 47%, 32% and 35% and 46%, respectively, especially at high-dose administration (p < 0.05). The expression of GPX (T2-81% and T3-82%) and SOD (T2-101% and T3-187%) were remarkably upregulated in T2 and T3 groups. Moreover, the relative gene expression of HSP70, interleukin-1 (IL1), Interferon γ (IFN-γ) and tumor necrosis factor-α (TNF-α) increased by 178%, 202%, 154% and 307%, respectively, especially at high-dose administration (p < 0.05). The results of the present study demonstrated that exposure to PS-NPs especially at high concentrations (500 and 1000 mg kg⁻¹ of diet) negatively influenced growth, health status-, antioxidant-, and immunity-related gene expression responses of zebrafish.

This research aimed to standardize the growth of two commonly cultivated herbs in the United Arab Emirates, basil (Ocimum basilicum L.) and coriander (Coriandrum sativum L.), within an aquaponic system. The study compared a recirculatory aquaponic system (RAS) with static aquaculture systems (for fish performance) and irrigated greenhouse cultivation systems (for herb performance). The project assessed growth, element composition, and aquaponic efficacy to determine the viability of aquaponics for these herbs. In the soilless (aquaponic) system, both herbs exhibited significantly enhanced growth parameters, including plant height, root length, leaf count, and fresh and dry weights, compared to conventional soil-based cultivation. This growth enhancement was attributed to the additional nutrients derived from fish waste in the aquaponic system. Furthermore, plants displayed significantly higher element levels, highlighting the effectiveness of aquaponics in nutrient delivery. Notably, the aquaponic system demonstrated superior antioxidant activity in both herbs. The study also revealed remarkable water use efficiency in the aquaponic system, with water savings exceeding 90% compared to conventional methods. These findings establish the efficiency and sustainability of aquaponic systems over traditional food production approaches, particularly in arid regions such as the United Arab Emirates. Utilizing an aquaponic system for these commonly cultivated herbs resulted in improved growth and resource efficiency, affirming its viability as an environmentally sustainable and efficient method of food production in desert climates.

In this study, 2 yeasts, Candida zeylanoides isolate Y12-3 (MN073455.1) and Hyphopichia pseudoburtonii isolate Y12-1 (MN073489.1), were isolated from rainbow trout hindguts. Their identity was confirmed by amplification of internal transcribed spacer (ITS) gene regions. Their in vitro probiotic properties showed that they were hydrophobic and did not inhibit bacterial growth. However, they displayed positive co-aggregation with several bacterial pathogens. It was interesting that Y12-1 and Y12-3 isolates survived and grew well in bile salt concentrations ranging from 0.6% to 1.5% and at low pH conditions. After a 35-day feeding trial, the results of dietary incorporation of the yeast isolates showed that serum myeloperoxidase activity was unchanged in the treated and control groups. Meanwhile, serum lysozyme activity in yeast groups was decreased significantly compared to the control. However, fish fed with Y12-1 had higher total protein, albumin, and globulin than other groups. Total cholesterol levels were decreased significantly in yeast groups compared to the control. Interestingly, the Y12-1 and Y12-3 groups showed higher survival (69.05% and 80.95%) after the challenge with Lactococcus garvieae compared to the control (45.24%). In brief, the aforementioned findings showed that Y12-1 and Y12-3 strains could be potential probiotic candidates for use in rainbow trout farming.