Aquaculture
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12348/2
Browse
Recent Submissions
- 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.
- Efforts to promote women’s participation, benefits, and empowerment in aquaculture entrepreneurship face persistent challenges rooted in patriarchal norms, policy frameworks, and local contexts. This article investigates how women’s entrepreneurship, supported by targeted programs, can help address these entrenched barriers. To do so, we employ the multi-level perspective (MLP) framework, which examines women’s entrepreneurial “niches” in relation to the dominant “regime” of local policies, public action, and gender norms. Our central aim is to understand how supporting women’s entrepreneurship can drive systemic change within aquaculture. Using a governance framework, we analyze strategies applied in two pilot interventions in Bangladesh, seeking to identify the limitations of current governance approaches and to propose strategies for establishing a more gender-equitable aquaculture regime. Our analysis reveals that existing strategic frameworks often fail to capture the agentic actions women take prior to program implementation and do not sufficiently address the influence of social and gender norms. Based on our findings, we recommend integrating gender transformative approaches and agentic strategies into governance frameworks, with the goal of challenging the prevailing regime and fostering greater gender equality in aquaculture. This approach recognizes women’s proactive roles and the importance of reshaping governance to support systemic gender equity.
- This study presents a literature-based review of Malaysia’s fishery and aquaculture sectors, examining their historical development, production trends, contributions, and challenges. Unlike existing studies that focus primarily on production trends or environmental concerns, this paper provides a policy-oriented perspective, linking production challenges to governance, economic constraints, and gaps in small-scale aquaculture and private-sector involvement. The study show that in 2022, Malaysia’s total fishery production reached 1.89 million metric tons, with aquaculture contributing 30%. While capture fisheries have stagnated due to overfishing and environmental pressures, aquaculture has expanded, playing a crucial role in post-Covid-19 recovery. However, sustainability remains a challenge due to climate change, water pollution, rising production costs, and regulatory barriers. To address these issues, the study recommends promoting sustainable fishing and aquaculture practices, enhancing research and development (R&D), streamlining regulatory frameworks, improving disease management, and expanding economic support and market access. These measures are essential to strengthening Malaysia’s aquaculture sector and ensuring long-term food security and economic resilience.
- Introduction: Tilapia (Oreochromis spp.) are among the most widely cultivated freshwater finfish species worldwide. The industry increasingly relies on tilapia strains selected for improved growth and other traits, particularly the Genetically Improved Farmed Tilapia (GIFT) strain. Despite the industry’s reliance on tilapia, knowledge of microbiome dynamics in reared tilapia remains limited. Understanding normal successional patterns in the microbiome of farmed tilapia is essential for identifying the characteristics that constitute a healthy microbial community. Methods: In this study, we assessed the microbiomes of tank and pond-reared GIFT tilapia by analyzing 568 samples, including water, gut, skin, and gill microbiomes of tilapia, from tank systems housing the source GIFT populations in Malaysia. We compared them to those reared in earthen ponds on another farm in Malaysia. Results: A total of 2,307 amplicon sequence variants (ASVs) were identified, encompassing a broad taxonomic diversity of 39 phyla, 86 classes, 180 orders, 299 families, 501 genera, and 399 species. Our findings elucidated distinct microbial community structures between rearing environments and across fish tissues, shedding light on intricate host-microbe interactions shaped by environmental conditions and management practices. The gut microbiome of tank-reared tilapia was dominated by Fusobacteriota (71.14%), in contrast to pond-reared fish (22%). At the same time, other taxa, such as Bacteroidota, Firmicutes_A, and Cyanobacteria, also varied markedly between environments and sampling periods. Skin and gill samples exhibited notable variability in the relative abundances of Fusobacteriota and Deinococcota between the two rearing sites. Principal Coordinates Analysis (PCoA) highlighted the distinct clustering of samples by rearing environment, particularly within gut microbiomes. Biomarkers such as Cyanobiaceae (pond water) and Sphingomonadaceae (tank water) underscored the impact of rearing conditions on microbial composition. Discussion: These results establish valuable baseline information on the types of bacteria associated with healthy, genetically defined (GIFT) tilapia strains. This foundational information will help identify specific microbial taxa associated with beneficial or detrimental effects on tilapia health and productivity across varying rearing conditions. Such insights can guide the development of practical microbiome monitoring strategies, such as early-warning tools for farm health, and inform targeted interventions to improve aquaculture performance.
- This Results Framework (RF) is based on the updated WorldFish (WF)’s Theory of Change (ToC) version in May 2023. The RF is built around a conceptual framework that focuses on determining the extent to which there is control over research results and contribution to development impacts. This document covers the details at all the above-mentioned levels as well as identifying roles and responsibilities and the ways of tracking the different outputs and outcomes. The high-level indicators were endorsed in 2023, during the annual retreat, taking reference of CGIAR indicators. This document also helps to identify (a) how the framework is operationalised and, (b) the key MEL activities and timelines to ensure the improvement of the program quality and efficiency of WF. For the full result framework table please refer to Annex 1, which provides more details of how each indicator will be reported, ways of segregation and aggregation, and frequency of data collection.
- Baseline characterization of aquaculture systems and livelihood in Nigeria objectives are to identify the prevalence and performance of different farming systems, as well as opportunities for interventions across the value chain that could enhance the performance and diversification of aquaculture in these areas. The study covered 524 farmers and 66 hatchery operators in two states, Delta and Ogun, using digital surveys.
- Global demand for seafood continues to rise, positioning aquaculture as a critical pathway for improving food security, nutrition, and rural livelihoods. In Kenya, the aquaculture sector remains constrained by structural challenges, with fish feed accounting for 60%–70% of production costs and limiting sectoral growth, particularly for smallholder farmers. This review critically analyzes Kenya's fish feed sector through an integrated PESTEL- SWOT framework, drawing on a scoping review of academic literature, policy reports, and sector development studies. The paper highlights key macro- level drivers, including fragmented policy implementation, dependency on imported ingredients, and climate- related risks, and connects these with internal industry dynamics such as innovation gaps and regional disparities in aquafeed accessibility. It presents a conceptual model illustrating how external and internal factors interact to shape aquafeed sector outcomes, positioning Kenya's experience within a broader Sub- Saharan Africa aquaculture context. The review identifies missed opportunities in scaling insect- and microalgae- based feed innovations, constrained by regulatory, technical, and market barriers. The discussion offers actionable recommendations for researchers, policymakers, donors, investors, and industry stakeholders, emphasizing the importance of integrated policy reforms, investment in local aquafeed technology development, and regional collaboration to strengthen feed supply resilience and address production bottlenecks.
- In the BMGF project WorldFish will support the sustainable growth of this extremely important aquatic food system to become a safe source of food for a growing population, providing important nutritional benefits to both women of reproductive age and young children. WorldFish will partner with NGOs, the private sector and government to drive systemic change within the aquaculture sector to support sustainable private sector development, using a market systems and consumer-led approach.
- In 2024, significant strides were made in advancing aquatic food systems that are climate-resilient, inclusive, and nutrition-sensitive. Through targeted innovation, scientific research, and strategic policy engagement, efforts supported communities in building resilience to climate-related shocks. The application of digital technologies, sustainable aquaculture practices, and co-management approaches contributed to improved livelihoods, while inclusive value chains and emerging technologies enhanced opportunities for women and youth. Nutrition-focused interventions further demonstrated the critical role of small fish and fish-derived products in addressing micronutrient deficiencies. Collectively, these developments highlight the growing importance of aquatic foods in global strategies for food security, public health, and climate adaptation.
- WorldFish has recently joined the Antimicrobial Resistance and One Health–South Asia (AMROH-SA) consortium—part of the Fleming Fund Regional Grants, a UK Department of Health and Social Care initiative—to help address the escalating threat of antimicrobial resistance (AMR) in aquaculture across Bangladesh, Nepal, Pakistan, and Sri Lanka. As a technical partner, WorldFish is contributing to the design of aquaculture-specific surveillance protocols for antimicrobial use (AMU) and resistance (AMR), delivering laboratory training, reinforcing One Health–oriented interpretation of surveillance data, and engaging aquaculture practitioners to promote responsible antimicrobial practices. These efforts aim to fortify sustainable aquatic food systems and inform evidence-based stewardship across the region.
- Development of the framework was undertaken in consultation with stakeholder representatives from SADC, particularly the SADC Regional Aquaculture Genetics Working Group, and the SADC member states via an online survey and a series of consultation meetings.
- Nigeria’s extensive coastline holds excellent potential for aquaculture but remains underutilized. This study examines stakeholders’ perspectives on the current status of coastal activities and their preferences for mariculture development in southwest Nigeria. The study gathered data from field observations, key informant interviews, and focus group discussions with stakeholders from the six coastal Local Government Areas in Ondo, Ogun, and Lagos states, representing both the private and public sectors. Descriptive statistics and thematic content analysis were employed to analyze the data. The findings revealed that coastal activities were limited to the culture of freshwater finfish, the wild recruitment of some brackish-water species, and artisanal fishing in the water bodies. Specifically, Clarias gariepinus and Oreochromis niloticus were the most cultured fish by 100 % and 75 % of the respondents, respectively. The farming of marine finfish, shellfish, and seaweeds is lacking due to insufficient technical knowledge (x‾ = 3.84), limited access to fish seeds (x‾ = 3.86) and feeds (x‾ = 4.59), and the absence of extension (x‾ = 3.82) and credit services (x‾ = 4.55). Despite these challenges, stakeholders identified opportunities for mariculture development, including the availability of wild finfish fingerlings (86 %) and broodstocks (55 %), hatchery facilities for induced propagation (64 %), and adaptable fish feeds (68 %). The respondents would prefer farming in brackish waters (41 %) and tidal ponds (28 %) to offshore sea cage installation (10 %). The study suggests that mariculture development in Nigeria could be tailored towards brackish species due to the availability of technical expertise on some of these species, their popularity, and general acceptability.
- Inland aquaculture is becoming an important source of animal-based protein in many low- and middle-income countries of Asia. In several of these countries such as Bangladesh the inland aquaculture sector is dominated by small-scale producers that rely on unimproved production practices. However, the heterogeneity of these producers is not well understood, leading to assumptions of low variability in both the underlying characteristics of aquaculture production systems, as well as their sustainability performance. This in turn can lead to the ineffective design and implementation of interventions and policies for the sustainable intensification of the sector. This study explores the differentiated characteristics, sustainability performance and preferences among carp producers in Bangladesh. We focus on Bangladesh as it is the 5th largest inland aquaculture producer globally, with the sector contributing significantly to livelihoods and food security. We undertake comprehensive in person surveys with 4540 carp producers across 54 regions of the country. We use 18 production variables to develop a nuanced typology of carp production systems using Principal Component Analysis (PCA) and Hierarchical Clustering Approach (HCA). We then assess whether these production systems have significantly different sustainability performance across eight socioeconomic and environmental indicators. Finally, we elicit the preferences of producers for improved carp species through three choice experiments. Overall, we identify four major types of carp production systems, characterized by very different production characteristics, sustainability performance and preferences for improved fish species attributes. Collectively, our results provide a nuanced picture of the carp aquaculture sector in Bangladesh, which moves beyond simple binaries (e.g., commercial vs. subsistence; intensive vs. extensive; large-scale vs. small-scale). This information can inform the development and implementation of fit-for-purpose interventions for the sustainable intensification of the sector.
- decussatus) collected from the Suez Canal near Ismailia, Egypt. The focus was on seasonal variations in contamination levels and the associated health risks to the local population. Bivalve samples were analyzed across four seasons (2023–2024) to identify harmful microorganisms and trace metal concentrations. Naturally occurring bacteria were isolated and identified, revealing prevalent species such as Streptococcus faecalis, Aeromonas spp., and Vibrio spp. These bacterial strains were purified and evaluated for their pathogenic potential. Mortality experiments demonstrated that S. faecalis and Vibrio spp. exhibited high pathogenicity, while Aeromonas spp. showed moderate pathogenicity. In parallel, atomic absorption spectrophotometry was used to measure the concentrations of heavy metals—Fe, Cu, Mn, Zn, Pb, and Cd—in the bivalves’ soft tissues. The results showed that the annual mean concentrations of Fe, Cd, Pb, Cu, and Zn exceeded FAO/WHO safety thresholds, particularly in winter, raising serious concerns regarding seafood safety. Overall, the findings highlight that bivalves function effectively as bioindicators of environmental contamination and underscore the need for strengthened monitoring and regulatory measures in the region to protect public health.
- This report provides valuable insights and recommendations for policymakers, practitioners, and other stakeholders seeking to support the development of small and medium-sized enterprises (SMEs) in the aquatic food sector in Southern Africa. The report highlights the importance of targeted capacity-building programs in addressing the specific needs of SMEs to enhance their capacity to deliver nutrient dense aquatic foods to address household food and nutritional insecurity and in turn promote sustainable development in the region.