Aquaculture International最新文献

Aquaponics (a sub-field of integrated agri-aquacultural practices (IAAS)) has emerged as a novel approach to combat global food security, reduce soil erosion and nutrient loss, and mitigate agronomic greenhouse gas (GHG) emissions. However, little remains known of potential consumer markets. Despite recent research throughout Europe, Central America, Australia, and the Middle East, this work represents the first large-scale evaluation of UK consumer understanding, assessment, and willingness to pay (WTP) for aquaponic products. Following analysis of 588 survey responses, we identify environmental awareness and green consumption, recognition of common UK eco-labels and sector-specific certification schemes, and consumer perceptions of aquaponics compared to conventional, locally sourced, and organic food production. Initially, 44% of survey respondents were familiar with aquaponics, with familiarity positively influenced by age and level of education. After presenting a definition of aquaponics (detailing its use and commonly cited socio-environmental benefits), consumer perceptions were mixed, with respondents broadly favourable to the practice despite uncertainty. Over 43% of consumers were willing to pay an associated price premium for aquaponic produce (valued, on average, as a 23% price increase over conventional alternatives). This willingness to pay was statistically in line with the organic market premiums and independent of prior familiarity with aquaponics as a food production system. These findings suggest a sizable consumer market for aquaponic produce and public interest in its sustainability benefits. Tailored marketing strategies could position aquaponic produce competitively alongside organic and environmentally friendly alternatives (irrespective of certification/eco-labelling), ensuring the long-term economic viability of the emerging aquaponics industry.

The biological effects of different particle sizes of bioflocs on Litopenaeus vannamei remain unclear. A 4-day short-term stress response experiment was conducted with small-sized group (SG), medium-sized group (MG), and large-sized group (LG), which were treated with bioflocs, and a control group (CG) treated with clear water. The diameters of the median particle size of SG, MG, and LG were 93.19 μm, 139.83 μm, and 173.09 μm, respectively; besides, the diameters of the coarse telomere of SG, MG, and LG were 181.40 μm, 279.60 μm, and 372.52 μm, respectively. The pathological observation of paraffin sections indicated varying degrees of tissue damage in SG, MG, and LG when compared with CG, with SG exhibiting more evident damage characterized by the presence of high-density vacuoles in the gill lumen. The activity of alkaline phosphatase and phenol oxidase exhibited varying degrees of fluctuation in all groups, with SG exhibiting a consistent downward trend. The activity of antioxidant enzymes, including superoxide dismutase, catalase, and glutathione peroxidase, was enhanced by the influence of bioflocs. Additionally, the content of malondialdehyde in SG was significantly higher than that in MG and LG after 2–4 days of stress (P < 0.05). Gill transcriptome analysis showed that CA, PDIA3, V-ATPase, and genes related to oxidative phosphorylation pathway and tricarboxylic acid cycle were significantly up-regulated under the stimulation of bioflocs. Compared with MG, MHC, TnI, and GS were significantly down-regulated in SG. Compared with LG, DanjC9 was significantly down-regulated in SG. Overall, the results showed that the short-term biological effects of small-sized bioflocs on L. vannamei were the strongest.

Shrimp production has adapted to recent disease outbreaks that have caused significant economic losses. Recognizing the importance of optimal shrimp nutrition is crucial for the sustainability of the industry. With increasing demand for high quality feeds that promote shrimp health, this study aimed to evaluate the effects of dietary nucleotide addition on performance, health status, nitrogen stress resistance, and ROI of Pacific white shrimp in an intensive synbiotic system. Experimental diets included a control group with no added nucleotides and diets with 75 mg kg⁻¹, 150 mg kg⁻¹, and 300 mg kg⁻¹. Shrimps, initially weighing 1.78 ± 0.02 g at a density of 100 shrimp m⁻², were randomly distributed and fed four times a day for 60 days. At the end of the trial, the nucleotide-addition diets had higher shrimp performance and protein composition than the control (p < 0.05). Notably, nucleotide supplementation improved gut morphology, evidenced by increased fold height, villus height, and enterocyte height. While Vibrio sp. and Bacillus sp. counts decreased across all treatments, yeast (fungi) showed an insignificant increase. Besides, no significant differences in survival rates, hemocyte counts, or gill histology were observed among treatments in ammonia and nitrite stress tests. Revenue generated from shrimp sales minus feed costs ranged from US$ 29,244 to US$ 30,542 ha⁻¹, with the N150 treatment exhibiting the highest return on investment. Consistently, nucleotide addition enhanced shrimp performance, protein composition, gut morphology, and return on investment. These results highlight the potential of nucleotide supplementation in optimizing shrimp feeding practices.

Diseases are the most significant constraint to the sustainable growth of aquaculture. Therefore, surveillance for aquatic animal diseases is essential for early detection of diseases which is important for management of endemic diseases and eradication or containment of exotic or emerging diseases. Often, many disease incidences in aquaculture go unreported due to unavailability of the field-level disease reporting mechanism. Therefore, there is a necessity of a mechanism that can connect farmers, field-level officers and fish health experts for strengthening the farmer-based disease reporting. Keeping the same in consideration, for improving the reporting of aquatic animal diseases in the country, an android-based GPS-enabled mobile application named as ‘ReportFishDisease (RFD)’ has been developed. Using the RFD app, the farmers can report incidence of disease in finfish, shrimps and molluscs on their farms to the field level-officers and fish disease experts as and when required, and get timely scientific advice for efficient management of diseases. The data regarding the diseases is being stored on temporal and spatial scale and can be used for mapping the disease cases. It is expected that the app would help in improving farmer-based reporting, getting scientific advice and reducing losses due to diseases.

This study investigated the effects of varying dietary protein and lipid levels on the growth performance and whole-body composition of climbing perch (Anabas testudineus) fry. Fish (initial weight: 0.34 ± 0.01 g) were fed nine semi-purified diets with three protein (35%, 40%, and 45%) and three lipids (6%, 8%, and 10%) levels for 60 days. While survival rates were unaffected by dietary treatments, fish fed a diet containing 40% protein and 8% lipid exhibited significantly higher (P < 0.05) weight gain (WG), specific growth rate (SGR), protein efficiency ratio (PER), and protein productive value (PPV), and lower feed conversion ratio (FCR) compared to other groups. Dietary protein and lipid levels had significantly (P < 0.05) affected whole-body composition. Second-order polynomial regression analysis showed that the optimal dietary protein and lipid requirements for climbing perch fry are in the ranges of 40.54—40.68% and 8.17—8.30%, respectively. These findings provide valuable insights for formulating nutritionally balanced diets to support optimal growth and development of A. testudineus fry.

Ranaviruses, from the Iridoviridae family, are globally distributed viruses that infect ectothermic vertebrates and cause significant harm to infected animals. The Nile tilapia (Oreochromis niloticus), crucial in global aquaculture, is susceptible to these viruses, particularly the frog virus 3 (FV3) species. The study investigated FV3 pathogenesis in this fish over a 60-day period, revealing the presence of inclusion bodies in different tissues, characteristic of FV3 infection. Macroscopic alterations were observed in infected fishes, including collapsed eyeballs showing edema, white spots on the liver, pale liver, submandibular erythema, dark pigmentation, reddish streaks, varying degrees of exophthalmos, and ascites with accumulation of proteinaceous fluid. Histopathological examinations revealed acute pancreatitis, hepatitis with necrotic areas, vacuolated and hyalinized renal tubules, necrotic and desquamative enteritis, melanomacrophage presence, inflammatory cell accumulation in the liver and pancreas, autolysis in areas of the intestine and pancreas, hemorrhagic vacuolated tubular areas, dissociated heart fibers, myocarditis, and cytoplasmic rarefaction. There was a statistically significant interaction (concentration/day) for hepatosomatic (p < 0.01) and splenosomatic (p < 0.05) indexes in animals infected with FV3. This study contributes to a better understanding of FV3 infection in Nile tilapia and raises the alarm that these fishes may host and consequently disseminate these viruses.

Due to the advantageous tidal movements and water exchange in coastal ponds, pangasius and tilapia farmers in Bangladesh benefit from higher water quality and nutrient levels, leading to higher quality fish at lower feed and water exchange costs. Therefore, the economic performance of coastal farms may be higher than for noncoastal farms. This study investigates the differences in technical efficiency and other economic performance indicators between coastal and noncoastal pond aquaculture farms. Data from 121 coastal and 479 noncoastal farms were analyzed using meta-frontier data envelopment analysis (DEA) and propensity score matching (PSM). Results show coastal farms are more efficient than noncoastal ones due to their advantageous locations. Locating new aquaculture farms to coastal regions could increase average output with the same inputs, follow industry best practices, save costs, and achieve higher returns on investment, reaching break-even at lower prices and quantities than noncoastal farms. Prioritize the development of aquaculture in coastal regions by providing incentives and infrastructure supports, as these areas offer competitive advantage over noncoastal regions.

In this study we describe for the first time the reproductive management of the ornamental fish L333, king tiger pleco, Hypancistrus sp., an endemic species from the Xingu River in the Amazon basin. A total of 56 fish were separated in 120 L aquariums (60 × 50 × 40 cm) with four breeding groups: Group 1 (1 male: 1 female); Group 2 (1 male: 2 females); Group 3 (1 male: 3 females) and Group 4 (1 male: 4 females). The study lasted for 180 days and a total of 145 spawns were observed, with every group spawning in the first month of the experiment. The highest mean of spawns per month was observed in Group 1 (2.04 ± 0.16), followed by Groups 4 (1.63 ± 0.50) and 2 (1.38 ± 0.34), while Group 1 had the lowest mean (1.00 ± 0.14). The highest eclosion rates were registered in Groups 1 (98.90 ± 0.92%) and 2 (93.50 ± 12.35%), followed by Groups 3 and 4, with 84.20 ± 5.30% and 82.60 ± 13.06% respectively. This study presented an alternative for breeding Hypancistrus sp., which can support the sustainable development of the pisciculture of loricariids and contribute to the conservation and preservation of species in natural environments.

Seaweed aquaculture is vital for economic resilience in Zanzibar’s blue economy communities. However, women’s participation in seaweed farming impact on their income remains underexplored. This study investigated the effects of women’s involvement in seaweed farming alongside selected socio-economic factors on their income levels. The study was descriptive and collected data in a cross-sectional survey involving 94 women seaweed farmers in the South Unguja district in Zanzibar. Ordinal logistic regression was used to analyze the relationships between women’s participation, socio-economic variables, and income levels. The study revealed that women’s participation in seaweed farming significantly inversely relates to higher income levels, indicating that the anticipated economic benefits are often not realized due to market challenges, limited empowerment, and operational issues. Similarly, farmer’s age significantly positively correlated with higher income levels, suggesting that older women tend to earn more. Conversely, other socio-economic variables, including education level, marital status, farming experience, business planning skills, access to seaweed equipment, and access to finance, did not show significant influence on income levels. These findings challenge assumptions about women’s economic empowerment in seaweed aquaculture and underscore the need to understand the barriers limiting income growth. To improve women’s economic empowerment in seaweed aquaculture, we recommend enhancing market access, diversifying income activities, and improving access to resources like equipment and finance.

Medicinal herbs are known for their diverse immunomodulatory properties, with bioactive compounds making them potential immunoadjuvants in vaccination. This study investigated the immunoadjuvant potential of ethanolic root extract from Asparagus racemosus (AREE) in rohu (Labeo rohita) fingerlings, using a formalin-killed Aeromonas hydrophila vaccine. A total of 360 rohu fingerlings were randomly divided into six groups, each with three replicate tanks. The fish were immunized via intraperitoneal injection with one of the following: phosphate-buffered saline (PBS), bacterin (B), bacterin combined with AREE (B + AREE), bacterin mixed with Freund’s complete adjuvant (B + FCA), FCA alone, or AREE alone. Serum, head kidney leucocytes, and head kidney tissues were collected 30 days post-immunization to assess antibody titers, antigen-specific leucocyte proliferation, and expression of immune genes (IL-1β, IFN-γ, IL-2, IgM, and IgT). Thirty days after immunization, ten fish from each group were challenged with A. hydrophila, and mortality was monitored for 2 weeks to calculate survivability. The B + AREE and B + FCA groups exhibited significantly higher (P ≤ 0.05) antibody titers, leucocyte proliferation, and immune gene expression compared to other groups. The post-immunization challenge revealed a significantly higher (P ≤ 0.05) survivability rate in the B + AREE (66.67 ± 3.33%) and B + FCA (70 ± 5.77%) groups. These findings suggest that AREE can serve as an effective immunoadjuvant with A. hydrophila bacterin, offering similar protection to Freund’s complete adjuvant in rohu against A. hydrophila infection.