Aquaculture
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12348/2
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- The presentation was presented at the International Workshop on Aquaculture Medicine & Aquatic Animal Health Management in Asia Pacific (AQUAMAP 2025). It discusses opportunities and challenges in enhancing biosecurity across aquaculture operations in the Global South, with a focus on Bangladesh. It outlines the drivers of disease emergence, such as live animal trade, poor regulation, and inadequate pathogen data. The work introduces a Participatory Biosecurity Gap Assessment (PBGA) and training module for finfish farms developed by WorldFish, the Department of Fisheries, FAO, BFRI, and CEFAS. Pilot assessments in Mymensingh identified twelve key pathogen pathways and potential biosecurity improvements. The study emphasizes equity, recognizing the need for inclusive, practical biosecurity processes that avoid excluding smallholder farmers, and promotes building resilience through education, diagnostics, vaccination, and better management practices.
- The presentation showcases WorldFish’s ongoing and planned initiatives on antimicrobial resistance (AMR), antimicrobial use (AMU), and residue monitoring in aquaculture under the One Health framework. It highlights extensive fieldwork in Bangladesh, including enumerator training, AMU/AMR surveys across tilapia-dominant systems, and the development of a comprehensive aquamedicine photobook cataloging over 300 brands, including critically important antibiotics. It also features results from antimicrobial residue testing of tilapia muscle samples using U-HPLC, revealing detectable residues of sulfamethoxazole and amoxicillin above permissible levels. Future plans include expanding surveillance to other aquaculture hubs and species, environmental residue testing, and developing rapid detection methods. The presentation underscores the need for cross-sectoral coordination, evidence-based surveillance tools, and stronger regulatory frameworks to mitigate AMR risks in aquatic food systems.
- The presentation provides a comprehensive overview of antimicrobial use in global aquaculture and its role in the emergence of antimicrobial resistance. It outlines patterns of antibiotic application, common pathogens such as Aeromonas, Vibrio, and Streptococcus, and historical examples of resistance spread through plasmids and gene transfer. Highlighting case studies from Asia, Africa, and Europe, it discusses unregulated antibiotic usage, limited vaccine access, and poor AMU monitoring in low- and middle-income countries. The presentation further describes WorldFish-led initiatives in Bangladesh, including AMU/AMR surveys, aquamedicine photobook development, wet-market sampling, and capacity-building workshops, emphasizing the need for harmonized surveillance, strengthened biosecurity, and policy-driven stewardship to mitigate AMR risks in aquaculture.
- This policy brief discusses the challenges SMEs face in leveraging trade opportunities under the African Continental Free Trade Area (AfCFTA). It also discusses measures that can help SMEs access trade benefits under the AfCFTA and contribute to the SADC’s health and nutrition agenda through improved access to safe and nutritious aquatic foods.
- The presentation highlights WorldFish’s integrated One Health initiatives in Bangladesh aimed at strengthening disease prevention, food safety, and AMR mitigation in aquaculture. It outlines collaborations with government and research partners to enhance biosecurity, antimicrobial use surveillance, and capacity-building across five upazilas in Mymensingh. Activities include AMU/AMR monitoring in tilapia farms, agrovet surveys, and antibiotic residue testing in aquaculture environments. Training programs on bacterial isolation, antimicrobial susceptibility testing, and molecular identification have built technical expertise among government and academic institutions. The presentation also addresses challenges such as unregulated antibiotic use, environmental pollution, and climate stress, while promoting solutions like digital tools, rapid diagnostics, biosecurity practices, and ecosystem-based aquaculture models for a more sustainable and resilient blue economy.
- The leaflet provides practical guidance for fish farmers and veterinary drug sellers on the responsible use of antibiotics in aquaculture. It explains what antibiotics are, outlines the risks of misuse such as treatment failure and AMR, and gives clear do’s and don’ts for both farmers and drug sellers. The key message emphasizes consulting professionals before using medicines, maintaining biosecurity, observing withdrawal periods, and avoiding unapproved or expired drugs. The leaflet concludes that biosecurity and good farm management are the most effective ways to prevent disease, and that prescription-based medicine sales protect both health and business.
- Selective breeding is a potent method for developing strains with enhanced traits. This study compared the growth performance and stress responses of the genetically improved Abbassa Nile tilapia strain (G9; GIANT-G9) with a local commercial strain over 12 weeks, followed by exposure to stressors including high ammonia (10 mg TAN/L), elevated temperature (37 °C), and both for three days. The GIANT-G9 showed superior growth, including greater weight gain, final weight, length gain, specific growth rate, and protein efficiency ratio, as well as a lower feed conversion ratio and condition factor compared to the commercial strain. The expression of growth hormone in the brain of the GIANT‐G9 increased significantly after 6 weeks, although it slightly decreased after 12 weeks. Growth hormone receptor 1 expression also increased significantly after 6 weeks. Muscle insulin-like growth factors (igf1 and igf2) levels up-regulated significantly only after 12 weeks in the GIANT‐G9. Under stress, serum enzymes (alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase (ALP)) were significantly higher in the GIANT‐G9, while the commercial strain had lower levels. No significant changes were observed in liver ALP activity among stressed strains. Under stress, the GIANT‐G9 exhibited marked upregulation of splenic Toll-like receptors (tlr2, tlr9, tlr21), myeloid differentiation primary response protein 88 (myd88), nuclear factor kappa B (nf-κB), interleukin (il) 1β, and il6. Notably, il6 expression was higher than il1β in the spleen, with the opposite pattern in the head kidney. In response to immune stimulation, globulin levels significantly increased in the GIANT‐G9 but with similar values to the stressed commercial strain. Myostatin expression increased in the spleen of the stressed GIANT‐G9. The commercial strain exhibited the best liver catalase and superoxide dismutase activities under stress, while the GIANT‐G9 showed increased liver glutathione-S-transferase (GST) activity after exposure to ammonia and temperature stress. Serum lysozyme activity increased in the stressed commercial strain and under temperature stress in the GIANT‐G9 but decreased under other stress conditions. Overall, the stressed commercial strain demonstrated higher survivability than the stressed GIANT‐G9. The study revealed significant interactions between strains and stress factors. The GIANT‐G9 exhibited higher growth rates but lower antioxidant and immune capacities compared to the commercial strain at the juvenile stage of life and production cycle.
- This brief highlights the vision, objectives, outcomes and strategy for WP2 of the AABS project - Integrated Multi-Trophic Aquaculture: Adapting and implementing Integrated Multi-Trophic Aquaculture tailored to local contexts in Asia and Africa.
- This report details the process of data input to WorldFish Genetic Improvement Program (GIP) Databases through Data Management System Graphical User Interfaces (Chang et al., 2021) (Figure 1). Outputs of GIP Data Management Systems are not described. Access to these systems and databases is restricted to authorized WorldFish personnel. Currently, four Data Management Systems support carp species (catla, rohu, silver carp), GIFT tilapia, Abbassa (GIANT) tilapia, and other tilapia species.
- This presentation was delivered at the workshop “Carp Genetic Improvement and Dissemination: Progress and Future Pathways” held on 24 September 2025 in Khulna, Bangladesh. It highlighted WorldFish’s work on the development and dissemination of improved strains of rohu (Labeo rohita), catla (Catla catla) and silver carp (Hypophthalmichthys molitrix) through family-based selective breeding, currently supported by the CGIAR Sustainable Animal and Aquatic Foods (SAAF) program. The initiative has already released G3 rohu, which has reached more than 200,000 farmers and demonstrated significantly higher growth and profitability. The presentation outlined the planned release of G5 rohu in 2026 and the forthcoming introduction of other improved strains, including G4 silver carp and G3 catla, in the coming years. It underscored the importance of long-term research and dissemination partnerships to sustain and expand these gains. Looking ahead, it emphasized opportunities to refine breeding objectives, apply advanced genomic tools, incorporate new traits and species, use cryopreservation to secure genetic resources, and strengthen quality-assurance systems to safeguard genetic integrity.
- The purpose of the Workshop was Build a shared vision and sense of ownership among stakeholders engaged in animal and aquatic food systems, enabling them to collaboratively address key food system challenges. In Bangladesh, millions of people depended on animal and aquatic food systems for both nutrition and livelihoods, yet these systems faced significant challenges, including overfishing, disease risks, climate impacts, and gender inequities. To address these challenges in a locally relevant and sustainable manner, SAAF organized a Co-design Workshop in Rangpur Division, a northern agroecological zone marked by diverse socio-political and climatic conditions. The workshop convened local stakeholders—including government officials, particularly from the Department of Fisheries (DoF), Department of Livestock Services (DLS), and Bangladesh Fisheries Research Institute (BFRI), as well as academicians from universities, farmer groups, researchers, and private sector actors—to collaboratively identify priority needs, co-develop solutions, and design context-specific interventions. By fostering participatory planning, shared ownership, and strong local partnerships, the workshop ensured that SAAF initiatives were inclusive, relevant, and positioned to improve nutrition, livelihoods, and resilience of people in Bangladesh.
- In March 2025, WorldFish conducted a comprehensive technical and biosecurity assessment of Jaweta Fish Farms Ltd, located in Homa Bay County, Kenya, as part of the Climate-Resilient Aquaculture Systems for Africa (CASA) Project. The evaluation aimed to determin the farm’s readiness to receive and manage Genetically Improved Farmed Tilapia (GIFT) fry. The assessment was conducted by WorldFish scientists Dr. Samuel Bekele Mengistu and Dr. Sameh Attia through on-site visits, technical meetings, and a standardized evaluation framework.
- A survey of feed ingredients was carried out in the six geopolitical zones to determine the availability, abundance, and effectiveness of these ingredients as considered for incorporation into fish feed for aquaculture production. A total of 516 well-structured questionnaires were administered to 228 ingredient producers and 288 ingredient sellers in the selected local government areas (LGAs), urban and rural markets, to obtain information on ingredient type, price, production capacity, and seasonality over a five-year period (2018-2022). It was observed that the ingredients were used in various ways, such as animal feeds, industrial use, and human consumption. The majority of the ingredients from producers reach the sellers through the market. The forms in which the ingredients were sold include grains, amounting to 64%; coarse form, 24%; powder form, 10%; and liquid form, 2%. The types of sellers operational are small-scale (51%), medium-scale (41%), and large-scale (8%), with 33% having more than 10 years of experience, 40% having 5 to 10 years of experience, and 27% having less than 5 years of experience. Based on the data collected, cassava can be found all year round. Maize, beans, nuts, soybeans, and sorghum were reported to be more abundant in the dry season; yam was observed to be available all year round but very expensive at the onset of rains until the third quarter of the year. Based on the sellers' opinion, fishmeal is found all year round. It was concluded that there should be an intensification of Black Soldier Fly Larvae (BSFL) production to further reduce the price of aquafeeds for increased aquaculture production.
- High feed costs driven by reliance on imported ingredients hinder aquaculture development in Zambia. Locally available animal protein alternatives offer a promising solution, but their digestibility remains underexplored. This study evaluated the apparent digestibility coefficients (ADCs) of two local caterpillars: mopane caterpillar or vinkubala (Gonimbrasia belina) and silkmoth caterpillar or tukanja (G. zambesina), as well as three small fish species, namely kapenta (Limnothrissa miodon), kakeya (assorted fish), and chisense (Potamothrissa acutirostris), for potential inclusion in juvenile GIFT tilapia (Oreochromis niloticus) diets. A reference diet with yttrium oxide (Y2O3) as a digestibility marker and test diets (70% reference diet, 30% test ingredient) were used. Fish were fed at 90% satiation for 6 weeks, with feces collected in the last 2 weeks. The ADC of the test diet ranged from 98% to 99% for dry matter (p > 0.05), while crude protein (80%–92%), crude lipid (90%–97%), and energy (78%–89%) were significantly different (p < 0.05), reflecting the effective utilization of these ingredients in the diet. The ADCs of the tested ingredients showed numerical differences, but high variability in standard deviations resulted in no statistical significance (p > 0.05). ADC of dry matter ranged from 54% to 62% in caterpillars and 67%–81% in fish, crude protein from 62% to 65% and 68%–82%, crude lipid from 66% to 74% and 68%–83%, and ash from 60% to 69% and 74%–83%, respectively. These findings highlight the potential of locally available Zambian ingredients to support sustainable and cost-effective aquafeeds for tilapia. However, the variability in digestibility values indicates the need for further investigation to optimize their inclusion in diets.
- This study aimed to identify and validate male-specific genomic markers for two economically significant aquaculture species: catla (Labeo catla syn. Catla catla) and silver carp (Hypophthalmichthys molitrix). Using conserved male-specific genomic regions from closely related species—rohu (Labeo rohita) and bighead carp (Hypophthalmichthys nobilis)—short sequence fragments were aligned to catla and silver carp genome assemblies to identify candidate male-specific markers. These markers were incorporated into DArTag panels and evaluated, according to read-count thresholds, in individuals of known visually-assessed or functional (i.e. reproductive) phenotypic sex (PSEX). Consistent with a XX/XY sex determination system, the sequences were expected to be present in males and absent in females. In catla, three markers predicted functional PSEX with 94.7 % accuracy. Notably 10 out of 123 genotyped catla dams were marker-assigned a genotypic sex (GSEX) of male, likely due to the presence of marker sequences in non-sex-determining genomic regions. For silver carp, 11 markers demonstrated a very high accuracy of 99.7 % in predicting visually-assigned PSEX. The markers and methods identified in this study represent promising tools for efficient and accurate sex determination in catla and silver carp, though further validation across different populations is recommended to ensure their broader applicability. The identified markers showed strong potential for practical application in aquaculture, particularly for the quantification of sexual dimorphism in immature fish and identification of sex-reversed individuals, in addition to their use in genetic improvement programs.
- The success of the Nile tilapia (Oreochromis niloticus) as an aquaculture species is partly the result of continuous selective breeding leading to high performing strains. These elite strains have been derived from breeding populations of diverse origins and crosses with other Oreochromis species. Owing to the complex and unique evolutionary histories of each strain, existing reference genomes of wild populations are unsuitable to implement genomic selection for beneficial traits such as growth or environmental resilience in aquaculture programmes. Here we generated a high-quality genome assembly and annotation of the WorldFish Genetically Improved Abbassa Nile tilapia (GIANT) elite strain using a combination of PacBio HiFi, and Omni-C Illumina sequencing. As a male Abbassa Nile tilapia was used for the generation of the genome assembly, we reconstructed both X and Y haplotypes, identifying both amhY and amhΔy on LG23 indicating that Abbassa likely shares the same sex determination system as GIFT, and thereby differs from the existing reference genome, whose sex determination loci are located on LG1.
- Nigeria’s aquaculture sector, vital for food security and rural livelihoods, is increasingly threatened by the unchecked spread of water hyacinth. This study applied a mixed-methods approach, combining 22 key informant interviews (KIIs), field observations, informal interviews, and a survey of 454 fish farmers to assess its impacts and farmers’ willingness to support control measures. Results show widespread recognition of negative effects, including reduced fish catch, poor water quality, damaged infrastructure, with strong community demand for intervention. On average, households are willing to contribute ₦2492 (USD 1.51) per month for 20 years to finance control measures. Econometric analysis indicates that willingness to pay (WTP) is shaped by the interaction of income and education, as well as gender and regional differences, rather than income alone. While education moderates income to increase WTP, the education–income interaction negatively affects participation. Notably, these contrasting effects on participation (negative) and WTP (positive) can be understood through the lens of collective action theory. These findings emphasize the need to integrate community perceptions with economic valuation to design inclusive and regionally tailored control strategies, strengthening resilience in Nigeria’s aquaculture sector.
- Cambodia’s ricefield ponds are small water bodies within or near rice fields that provide multiple benefits beyond water storage. They serve as fish refuges during dry spells, support pest control, and create opportunities to integrate fish, rice, vegetables, and livestock into one climate-smart farming system. Research in Takeo and Prey Veng has shown that improved pond management can boost fish production by 67%, enhance biodiversity, and provide two crop cycles, leading to greater income and resilience for farming households. However, challenges remain, including water shortages in the dry season, limited feed, pesticide use, and gaps in farmer knowledge, which can be addressed through better pond design, integrated pest management, low-cost supplementary feed, and farmer-to-farmer learning. Demonstrations under the CGIAR Multifunctional Landscapes Initiative show that integrated ricefield pond systems can generate up to four times more value than rice alone, while reducing chemical inputs and strengthening ecosystems. This “One Family, One Pond” model promotes sustainable food production, natural resource use, and adaptation to climate change. Recognized in Cambodia’s national climate commitments (NDC 3.0), the approach offers benefits at household, community, and landscape levels by improving food security, conserving biodiversity, reducing costs, and building resilience. More than just rice or fish, ricefield ponds represent a holistic pathway for nearly a million Cambodian households toward resilient and sustainable livelihoods.
- Asia–Africa BlueTech Superhighway (AABS) will help Nigeria address its fisheries and aquaculture challenges by leveraging South–South collaboration to improve sustainability, resilience and prosperity in coastal communities. Through evidence-based models and partnerships, AABS will enhance the adaptive capacities of small-scale fish workers and farmers, mitigating the effects of climate change and increasing the sustainability of fish production. By focusing on Nigeria’s vulnerable coastal regions, the initiative will not only support the government’s goals but also ensure that the livelihoods of these communities are more secure and equitable.
- This paper offers new insights into gender norms, roles, participation, relations, and benefits derived by women and men engaged in the aquaculture sector in Ogun and Delta States in Nigeria. Data were collected using mixed methods, including structured surveys of 410 farmers, 175 market actors, and 53 input suppliers, 116 semi-structured key informant interviews, and 11 focus group discussions (FGDs). Overall results of the study revealed the linkages within the aquaculture value chain, which was highly gendered, with men dominating all the three main stages of the value chain as indicated by Duncan's index of dissimilarity of 17.35%. Results also revealed a gender difference in the value of assets, ownership, and wage rate among men and women participants in paid labor in the input supply and fish trading segments. Men tended to realize more profits than women, indicating an imbalance in the distribution of benefits by gender along the aquaculture value chain. Results revealed that the participation of women in decision-making was relatively high, attributable to their involvement in aquaculture value chain activities. The findings highlight the need for governments, development agencies, and non-governmental organizations to address gender disparities in policies designed to improve the imbalance in the distribution of benefits between women and men.