Browsing by Author "Langi, Sandra"
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Item Food system innovation platforms as a pathway towards regenerative inclusive food systems(Wageningen University & Research, 2023) Froebrich, Jochen; Groot, Annemarie; Adokorach, Molly; Aranguiz, Adolfo Alvarez; Andeweg, Karin; Omedo, Bockline Bebe; Beekman, Gonne; Bennink, Viola; Berecha, Gezahegn; Alho, Carlos Brazao Vieira; Brummelhuis, Amber; Kajobe, Robert; Langi, Sandra; Malingumu, Richard; Nabulime, Maureen NorahFood systems in East Africa are under pressure. Climate change, biodiversity loss, natural resource depletion, and declining soil health are having an impact. Hunger continues to grow. Recent developments, such as the increasing price of inputs like mineral fertilisers, make the need for change even more urgent. Many agree that to reverse these trends requires a fundamental change. We need a transition towards Regenerative Inclusive Food Systems. In another booklet we describe what Regenerative Inclusive Food Systems may look like, why we need them and what lessons we have learned in the REFOOTURE project on the transition towards such food systems.Item Histological features of the gastrointestinal tract of elongate tigerfish, Hydrocynus forskahlii (Cuvier, 1819), from Lake Albert(Springer Nature, 2024-05-10) Kasozi, Nasser; Iwe, Gerald D.; Langi, Sandra; Namulawa, Victoria T.; Walakira, JohnThe tigerfsh (Hydrocynus forskahlii) is an important food fsh in diferent regions of Africa. As such, interest in its performance and nutritional requirements as a potential candidate for aquaculture is increasing. Characterization of the morpho-histological features and functions of the gut provides valuable insights into the feeding physiology and digestive system of fsh species. An investigation of the morpho-histological features of the gastrointestinal tract of H. forskahlii captured from Lake Albert was conducted over an eight-month period. The digestive tract of H. forskahlii is characterised by a short oesophagus, well-developed and distensible stomach and moderately long intestine. The oesophagus had a higher abundance of mucous-secreting goblet cells compared to other digestive tract tissues. The stomach had a bag-like shape for swallowing large prey and was distinguishable into the cardiac, fundic and pyloric regions. Both the cardiac and fundic regions of the stomach had numerous gastric glands, whereas the pyloric region had large compound folds consisting of pseudo-stratifed columnar epithelium. Many goblet cells were also observed in the mid and posterior regions of the intestine. The relative length of the gut of the H. forskahlii was 1.27±0.03 cm, and it had a total of 20–22 pyloric caeca. The liver was observed to be divided in lobules by a central vein contained within connective sheets. Irregular cords of hepatocytes were also visible throughout the parenchyma.The histological features of the H.forskahlii gut observed in the present study are consistent with those of carnivorous and omnivorous fsh.Item Integration of probiotics in aquaponic systems: an emerging alternative approach(Springer Nature, 2023-08-28) Kasozi, Nasser; Iwe, Gerald Degu; Walakira, John; Langi, SandraThe increasing demand on water resources, reduced land for agriculture, and concerns over food and nutrition security have prompted the evolution of innovative and complex food production systems. In this context, efficient and sustainable food production systems such as aquaponics are viewed as an important and environmentally friendly technology for adaptation under resource-limited environments. Producing food in soilless systems is a promising strategy, as this method utilizes significantly less water than traditional agriculture. However, optimizing growing conditions to enhance crop and fish yields in aquaponics is frequently ambiguous and is often not economically feasible. One of the strategies to improve plant yields and supply of nutrients in aquaponics is the application of probiotics. With this strategy, the crop yields in aquaponics are improved via a variety of mechanisms, including nitrogen fixation, solubilization of mineral nutrients, organic matter mineralization, plant hormone modulation, and biocontrol. As a result, incorporating probiotics in aquaponic systems is a strategy for mitigating environmental effects and advancing sustainable agriculture. This review paper provides the current knowledge of the use of probiotics in aquaponics. Suggestions for further studies on the effects of probiotics in aquaponic systems are proposed. Through literature review, integrating probiotics into aquaponic systems has the potential to improve nutrient supply, modulation of water quality parameters, and microbial communities, which are key processes in enhancing the productivity of aquaponic systems.Item Moving towards regenerative inclusive food systems(Wageningen University & Research, 2023) Froebrich, Jochen; Groot, Annemarie; Adokorach, Molly; Aranguiz, Adolfo Alvarez; Andeweg, Karin; Omedo, Bockline Bebe; Beekman, Gonne; Kajobe, Robert; Langi, Sandra; Malingumu, Richard; Nabulime, Maureen NorahThe food systems in which people in East Africa produce and consume their daily meals are in crisis. Hunger continues to grow. Climate change, biodiversity loss, depletion of natural resources and declining soil health are the factors making the lives of farmers and other actors in these food systems increasingly difficult. This booklet is about Regenerative Inclusive Food Systems. These are based on the idea that for the food system to change for the better, fundamental changes are needed in society – in the agricultural sector and among both consumers and policy makers. There are already many initiatives that aim to improve the current situation by focussing on sustainable outcomes, most of which are based on technology and economics. Regenerative Inclusive Food Systems approach go beyond this, by focussing on how to get to these outcomes, where the capacity to regenerate is key. Regenerative Inclusive Food Systems are about the motivation and capacities of people in the food system, starting from local communities: about their motivation and capacities to reflect on the situation, to create a common vision, and to inspire others to make a change. With this approach, interpersonal relationships will become stronger, as people take care of each other and pursue paths for equal opportunities in transforming their food systems, while leaving no one behind. Moreover, in Regenerative Inclusive Food Systems, people are seen as being embedded in nature and their relationship with nature is therefore fundamentally different. The ecosystem is regenerated, including the rich life in the soil beneath our feet.Item Nutritional requirements and effect of culture conditions on the performance of the African catfish (Clarias gariepinus): a review(Taylor & Francis, 2024-01-23) Langi, Sandra; Maulu, Sahya; Hasimuna, Oliver J.; Kapula, Veronica Kaleinasho; Tjipute, MartinAquaculture is crucial for global food and nutrition security due to the inability of wild harvests to meet increasing demand. Africa’s contribution to aquaculture is generally low, despite its potential for economic development, food security, and reduced unemployment. The study focuses on the African catfish (Clarias gariepinus) a freshwater fish species that is widely farmed for food in Africa and other parts of the world. Proper nutrition is essential for the growth and development of the fish, and understanding their nutritional requirements is critical for producing healthy and high-quality fish. This review article provides an overview of the knowledge on the nutritional requirement of the African catfish, including protein, lipids, carbohydrates, vitamins, minerals, and amino acids. The recommended protein content for juvenile fish is between 40 and 50% and for adult fish is between 30 and 40%. Based on the reviewed studies, the recommended amount of methionine in C. gariepinus diets ranges from 18.7 to 29.7 g/kg of protein while the lysine requirement ranges from 44.9 to 62.2 g/kg protein). The recommended lipid content in the diet is between 5–15% for juvenile fish and 5–10% for adult fish. The African catfish requires a low-carbohydrate diet, with recommended carbohydrate content between 26 and 32%. They require a variety of vitamins, including vitamin A, vitamin D, vitamin E, and vitamin C, as well as minerals, such as calcium, phosphorus, and potassium. Clarias gariepinus also require a variety of essential and non-essential amino acids. Besides the nutritional requirements, culture conditions also have a significant effect on the feed performance. The recommended conditions include temperature ranging from 28 to 32 °C, Light intensity of 150 Lx, 12D:12L photoperiod, and stocking density in earthen of 7 fish m−3. Overall, understanding the nutritional requirements of C. gariepinus is crucial for the successful fish farming and sustainable aquaculture. Information in this review will be built to further guide the development of feeds for C. gariepinus.Item Prospects for aquaculture development in Africa :(Center for Development Research (ZEF), 2022-01) Hinrichsen, Etienne; Walakira, John K.; Langi, Sandra; Ibrahim, Nabil Ahmad; Tarus, Victoria; Badmus, Olanrewaju; Baumüller, HeikeAfrican aquaculture production has gradually increased over the years, but progress is still slow. Given large variations between African countries with regard to the availability of water, the macro-economic context, access to capture fisheries resources and other factors, the performance of African countries in aquaculture cannot be considered only by absolute production levels or contribution to GDP. Additional indicators must be considered that also take into account the role of aquaculture as a source of food supply as well as other macro-economic variables, such as population size and natural resource endowment. To this end, relevant data were collected for 54 African countries covering a range of indicators, drawing on existing data collections of the World Bank and the Food and Agriculture Organization of the United Nations (FAO). The need for development of the sector and its potentials are identified by assessing African countries’ performance with regard to the role of aquaculture as a source of food supply, absolute and per capita production volumes and values (including changes over time), and the economic importance of the sector. The contribution of aquaculture to national fish supply is highest in Egypt. Lesotho features second in this indicator, but much of the production is targeted at the export market as confirmed by the low level of per capita fish supply. The greatest gap between per capita fish supply and average African fish supply was recorded for Ethiopia (followed by Guinea-Bissau and Sudan). Egypt also leads African aquaculture in terms of absolute production volumes and value (followed by Nigeria). In 2018, Egypt’s production was more than twice the total production of all the remaining African countries put together. In terms of production growth rates over the past decade, however, other countries stand out, including Rwanda, Burundi, Lesotho and Benin, albeit starting from a low base. Lesotho, South Africa and Mauritius lead in the value of production per tonne due to the cultivation of a number of high-value species for export. In terms of the economic importance of the aquaculture sector, its contribution to GDP is highest in Egypt, followed somewhat surprisingly by Lesotho, a country in which there was no aquaculture a mere two decades ago and where today the sector is a significant earner of foreign currency. Egypt also leads with regard to output relative to available renewable water resources (followed by Uganda). The study outlines a number of policy and investment priorities to support the growth of a sustainable, climate-resilient and equitable aquaculture sector in Africa as an integral part of food systems. Particular attention should be paid to engaging and building the capacities of small-scale actors in this sector to contribute to local food security, employment and income generation.Item Recent advances in the utilization of insects as an ingredient in aquafeeds:(Elsevier, 2022-08-08) Maulu, Sahya; Langi, Sandra; Hasimuna, Oliver J.; Missinhoun, Dagoudo; Munganga, Brian P.; Hampuwo, Buumba M.; Gabriel, Ndakalimwe Naftal; Elsabagh, Mabrouk; Van Doan, Hien; Abdul Kari, Zulhisyam; Dawood, Mahmoud A.O.The aquafeed industry continues to expand in response to the rapidly growing aquaculture sector. However, the identification of alternative protein sources in aquatic animal diets to replace conventional sources due to cost and sustainability issues remains a major challenge. Recently, insects have shown tremendous results as potential replacers of fishmeal in aquafeed. The present study aimed to review the utilization of insects in aquafeeds and their effects on aquatic animals' growth and feed utilization, immune response and disease resistance, and fish flesh quality and safety. While many insect species have been investigated in aquaculture, the black soldier fly (Hermetia illucens), and the mealworm (Tenebrio molitor) are the most studied and most promising insects to replace fishmeal in aquafeed. Generally, insect rearing conditions and biomass processing methods may affect the product’s nutritional composition, digestibility, shelf life and required insect inclusion level by aquatic animals. Also, insect-recommended inclusion levels for aquatic animals vary depending on the insect species used, biomass processing method, and test organism. Overall, while an appropriate inclusion level of insects in aquafeed provides several nutritional and health benefits to aquatic animals, more studies are needed to establish optimum requirements levels for different aquaculture species at different stages of development and under different culture systems.Item REFOOTURE: A project to advance regenerative inclusive food systems(Wageningen University & Research, 2023) Froebrich, Jochen; Groot, Annemarie; Adokorach, Molly; Aranguiz, Adolfo Alvarez; Andeweg, Karin; Omedo, Bockline Bebe; Beekman, Gonne; Bennink, Viola; Kajobe, Robert; Langi, Sandra; Malingumu, Richard; Nabulime, Maureen NorahDespite all the efforts in recent decades, food insecurity, poverty and nature degradation are on the rise in East Africa. The REFOOTURE project believes fundamental change is needed to solve these issues. They can only be solved by transforming food systems into Regenerative Inclusive Food Systems. In Regenerative Inclusive Food Systems, people are seen as part of nature, nurturing nature rather than exploiting it. In these food systems, nature and social relationships are regenerated, supporting food security and resilient livelihoods. The REFOOTURE project, which was launched in 2020 with funding from the IKEA Foundation, aims to foster Regenerative Inclusive Food Systems in three East African countries: Ethiopia, Kenya, and Uganda. The key idea behind REFOOTURE is that innovation is crucial to fostering social, technological, and institutional transformation towards Regenerative Inclusive Food Systems. These innovations should be place-based, rooted in the specific characteristics of a place which is in some way meaningful to the people living there. Local communities, their territory and their surroundings determine the place-based potential for innovations.Item Replacement of fishmeal using poultry-based protein sources in feeds for pikeperch (Sander lucioperca, Linnaeus, 1758) during grow out phase(Springer Nature, 2022-09-05) Langi, Sandra; Panana, Edson; Alloo, Ceder; Van Stappen, Gilbert; Meeus, WouterA 61-day growth experiment was carried out to evaluate the potential of a poultry-based protein (PBP) comprising of feather meal (FeM) and poultry meat and bone meal (PMBM), as a fishmeal (FM) substitute in diets of juvenile pikeperch (Sander lucioperca, L.). Pikeperch (initial body weight 113.12 g) were randomly distributed in groups of 250 fish in twelve 1.8 m3 circular recirculating aquaculture system (RAS) tanks, and fed four isonitrogenous (52% crude protein), isolipidic (17% crude lipid), and isocaloric (21.80 KJ/g energy) experimental diets. The feeds contained FM as the primary protein source (PBP0) or PBP replacing 20 (PBP20), 40 (PBP40), or 60% (PBP60) of the FM. Based on appetite and calculated uneaten feed, the feeding rate was initially set at 1.5% and subsequently reduced to 1% of the total tank biomass towards the end of the study. At the end of the experiment, the average feed intake ranged from 1.93 to 2.00 g/fish/day (p > 0.05). No adverse effects on growth and feed efficiency were observed in fish fed diets PBP0, PBP20, and PBP40. Particularly, the final body weight (FBW) (248.73, 240.11 g), feed conversion ratio (FCR) (0.86, 0.91), specific growth rate (SGR) (1.29, 1.35%/day), and protein efficiency ratio (PER) (2.20, 2.12) of fish fed PBP20 and PBP40 were not significantly different from the control PBP0 whose values ranged from 248.11 g, 0.89, 1.27%/day, and 2.18, respectively (p > 0.05). In all treatments, the condition factor (k) (1.31 to 1.33), hepatosomatic index (HSI) (2.35 to 2.70%), visceral somatic index (VSI) (6.87 to 7.19%), and whole-body composition of crude protein (57.77–58.28%) and crude lipid (23.85–26.85%) were not significantly influenced by the dietary PBP inclusion level (p > 0.05). However, whole-body ash content was significantly higher in PBP60 (14.66%) compared to the other treatments (12.57–14.43%) (p < 0.05). Based on the results from this study, up to 40% of FM can be replaced by PBP in diets for pikeperch juveniles without compromising growth performance and feed utilization.Item Scaling aquaculture for food security and employment in Africa – Insights from Egypt, Kenya and Nigeria(Center for Development Research, 2023-06) Walakira, John K.; Hinrichsen, Etienne; Tarus, Victoria; Langi, Sandra; Ibrahim, Nabil Ahmad; Badmus, Olanrewaju; Aziz, Andrew; Baumüller, HeikeAquaculture is the fastest growing food sector in the world and now accounts for more than half of the fish consumed globally. However, the sector in Africa remains in its infancy, with the notable exception of Egypt, one of the world’s largest producers. This paper provides a thorough analysis of the sector in the selected countries of Egypt, Kenya and Nigeria to help identify investment and policy priorities that can sustainably advance aquaculture across Africa to boost income and employment, rural development and food security. The analysis focuses on nine themes to ensure a comprehensive overview of the sector and to better understand the relative strengths and weaknesses in each country: sector trends, national policy frameworks, government institutions, natural resources to support aquaculture, sector-specific innovation, feed and seed, market access, public-private partnerships, and sectoral impacts. With these in mind, the paper provides a series of recommendations for African policymakers and investors aimed at improving sectoral development across the continent. Among other factors, the recommendations highlight the need to not only increase productive capacity but also linkages to markets and consumers, adopt national policies that provide targeted support to high-potential areas, increase local research capacities and scaling of research results, decentralize seed and feed production for improved access, and promote sustainably produced fish as a promising source of animal-derived protein.