Lakes across the globe, including the Volta Lake in Ghana, face insidious threats from pollutants driven by high dependency on aquatic ecosystems. Cage aquaculture is expanding in Africa due to its potential to address food insecurity, provide livelihoods, and contribute to local economies. However, the uncontrolled expansion of cage aquaculture can have significant negative impacts on water resources, including environmental footprints that threaten biodiversity. Considering the intensification of cage aquaculture on the Volta Lake, we argue for a shift to sustainable alternative aquaculture systems. Deepening stakeholder collaborations are needed to enhance competence in mapping inland aquaculture areas, identifying eco-friendly alternatives, and strengthening aquaculture regulations and their enforcement in general and cage culture in particular on Lake Volta. This approach would promote best management practices. While competence building must be a continuous process to address knowledge gaps, the establishment of workable preparedness plans is needed in the event of emergencies. As the Lake is a hotspot for certain fish pathogens, implementing these strategies can reduce disease risks and subsequently decrease the development of resistance associated with excessive antimicrobial use in farmed fish.
Lakes around the world, including Ghana’s Lake Volta, are facing insidious threats from pollutants due to high dependency on aquatic ecosystems. Cage aquaculture is expanding across Africa because of its potential to address food insecurity, provide livelihoods, and boost local economies. However, the uncontrolled expansion of cage aquaculture can have significant negative impacts on water resources, including environmental footprints that threaten biodiversity. Given the intensification of cage aquaculture for tilapia farming on Lake Volta, we advocate for a transition to inland-integrated aquaculture systems that promote circularity. Strengthening stakeholder collaboration is essential for enhancing competence in mapping inland aquaculture areas, identifying eco-friendly alternatives and reinforcing aquaculture regulations, with particular emphasis on cage culture on Lake Volta. These strategies can reduce the pressures imposed by tilapia cage farms on the lake while promoting best management practices. Additionally, capacity building must be an ongoing process to address knowledge gaps, including the development of effective preparedness plans executed during emergencies. The ongoing pollution from illegal mining in the Black Volta River, a tributary of Lake Volta, along with endemic diseases in the lake, further compounds fish health and welfare issues. This underscores the urgent need to implement inland transition strategies to protect the lake, mitigate disease spread, and ensure safe fish food production.
Education, research, and biosecurity have global recognition as strong pillars of sustainable aquaculture development. In many developing countries, insufficient knowledge and awareness among stakeholders regarding the relevance of education, research, and biosecurity have influenced aquaculture sustainability negatively. To uncover the gaps in education, research, and biosecurity practices in aquatic animal health management, we conducted a questionnaire-based study in various East and West African countries. By adopting the methodology of self-reporting data, we invited a significant number of individuals to participate in the study. In the end, 88 respondents contributed, with the majority from Ghana (47) and Kenya (20), and 21 respondents from five other East and West African nations. The results revealed substantial educational gaps, including the need for practical training in aquatic animal health management, nutrition, and genetics. Respondents also emphasized the importance of creating additional national aquaculture research institutions and augmented funding to enable them to address industry needs. Governments of the represented nations should actively intervene by providing the essential logistics and capacity to support aquaculture research and development. Informed government involvement is paramount for bridging the disconnection among all stakeholders, as revealed in the results. Furthermore, the lack of biosecurity measures and the understanding of the importance of biosecurity measures in the industry addressed through awareness creation. Creating awareness on biosecurity underpinned with national aquaculture biosecurity policies can prevent disease incidences in the industry. The outcomes of this study can serve as a vital working document to enhance aquatic animal health management in East and West Africa, thereby fostering sustainable and resilient aquaculture.
Farming seabass (Dicentrarchus labrax) is an essential activity in the Mediterranean basin including the Aegean Sea. The main seabass producer is Turkey accounting for 155,151 tons of production in 2021. In this study, skin swabs of seabass farmed in the Aegean Sea were analysed with regard to the isolation and identification of Pseudomonas. Bacterial microbiota of skin samples (n = 96) from 12 fish farms were investigated using next-generation sequencing (NGS) and metabarcoding analysis. The results demonstrated that Proteobacteria was the dominant bacterial phylum in all samples. At the species level, Pseudomonas lundensis was identified in all samples. Pseudomonas, Shewanella, and Flavobacterium were identified using conventional methods and a total of 46 viable (48% of all NGS+) Pseudomonas were isolated in seabass swab samples. Additionally, antibiotic susceptibility was determined according to standards of the European Committee on Antimicrobial Susceptibility Testing (EUCAST) and Clinical and Laboratory Standards Institute (CLSI) in psychrotrophic Pseudomonas. Pseudomonas strains were tested for susceptibility to 11 antibiotics (piperacillin-tazobactam, gentamicin, tobramycin, amikacin, doripenem, meropenem, imipenem, levofloxacin, ciprofloxacin, norfloxacin, and tetracycline) from five different groups of antibiotics (penicillins, aminoglycosides, carbapenems, fluoroquinolones, and tetracyclines). The antibiotics chosen were not specifically linked to usage by the aquaculture industry. According to the EUCAST and CLSI, three and two Pseudomonas strains were found to be resistant to doripenem and imipenem (E-test), respectively. All strains were susceptible to piperacillin-tazobactam, amikacin, levofloxacin, and tetracycline. Our data provide insight into different bacteria that are prevalent in the skin microbiota of seabass sampled from the Aegean Sea in Turkey, and into the antibiotic resistance of psychrotrophic Pseudomonas spp.
Abstract Aquaculture developmental plans represent a nation's determination for self‐reliance on domestic fish production through resilient aquaculture. This study reviewed the 2012 Ghana National Aquaculture Development Plan (GNADP) and sought inputs from industry stakeholders to inform GNADP 2023 using the ecosystem approach to aquaculture (EAA). In furtherance of this, we also investigated the justifications for antibiotic treatments including the assessment of the sector that is supposed to regulate aquaculture growth. The findings suggest that GNADP 2023 must be strategized to address industry sustainability bottlenecks identified as input availability and quality, permitting, regulation and enforcement, financing schemes and technical expertise. In terms of technical expertise, the inclusion of women in aquaculture can diversify the skill sets for the improvement of capacity and competence in good aquaculture practices and fish health management. Sector partnerships can aid in leveraging the expertise and resources among sectors to address persistent industry issues. The justifications for antibiotic treatments are disease management, prophylactics, antibiotic availability, application, and effectiveness, capacity and competence, including regulation and enforcement. This also comprised the sense of ownership and responsibility as farmers feel they must safeguard their investment. It is therefore important for farmers to pursue preventative aquaculture biosecurity measures. The government sector was selected predominantly to regulate aquaculture growth. We however recommended a participatory approach as this could facilitate peer regulation to enhance the regulation and enforcement of aquaculture regulations. The findings in this study are worth considering as it pioneers the adoption of the EAA framework for aquaculture developmental planning in Ghana.
Unusual fish mortalities in aquaculture threaten global food security and carry significant socio-economic burdens. In 2018, Nile tilapia ( Oreochromis niloticus ) suffered unusual patterns of mortalities, attributed to disease-causing agents in Lake Volta cage aquaculture. In recent times, disease investigations have shifted from single to consideration of multiple factors to understand the puzzling range of causal risk factors. This study therefore aimed at expanding on tilapia mortality risk factors, while documenting fish health and Lake Volta management practices for sustainable aquaculture. We interviewed relevant aquaculture stakeholders operating on Lake Volta and conducted thematic analysis on their responses to map out mortality risk factors and management practices. The identified risk factors were conceptualized in established models of causation web and Social-Ecological System to explain the practical significance of the findings. The results showed that the risk factors of tilapia mortalities are a combination of pathogens and non-infectious factors mediated by weak law enforcement. The results further suggested mortality reinforcing mechanisms through the horizontal transmission of pathogens, namely, Streptococcus agalactiae and Infectious Spleen and Kidney Necrosis Virus. Moreover, the recognition of weak enforcement as a possible factor reinforcing human activities is a non-infectious route that can be deleterious to fish health. Health management practices comprised phytotherapy, vaccination, heat shock treatment, biological controls, and best husbandry practices. Lake management involves creating a waterfront buffer of 85.34 m, surveillance, and executing the framework guiding aquaculture development on the Lake. The findings are suggestive of complementary quantitative studies that augment the qualitative evidence herein. Such follow up studies can disclose precise mortality risk factors to inform policy directives and effective remedial strategies that can secure fish and lake health.
