Efficiency and Sustainability of Alternative Protein Sources for Livestock Production in Sub-Saharan Africa: A Systematic Review and Meta-Analysis

Owing to an increasing world population and a rising demand in protein for food and feed, alternative protein sources are needed. In addition, existing food and protein supplies such as wild and farmed fish need to be secured. Insects and more specifically the black soldier fly (BSF;Hermetia illucens) larvae, are discussed as an alternative animal protein source and a potential fish meal (FM) replacer in aquaculture. They can be sustainably reared on biogenic residues. In a literature study, the technical potential of occurring biogenic residues in Germany for the production of BSF larvae is estimated and their suitability as a FM replacement in aquafeed for the production of rainbow trout is evaluated. According to literature, up to 50% of FM can be substituted by BSF larvae meal in the feed of rainbow trout. For the annual German rainbow trout production of 8,466 t, 2,699 t BSF larvae meal (40.7% protein d.m.) is required to replace 1,556 t FM (70.9% protein d.m.). The demand for biogenic residues to feed the BSF larvae amounts to 22,942 t (d.m.). A large amount of biogenic residues occurring in Germany, such as forestry residues, animal excrements, straw and the biogenic fraction of municipal waste, have too poor nutrient contents or are inapplicable due to legal restrictions as feed for farmed animals. However, an alternative utilisation of approximately 1.26 Mt (d.m.) of biogenic industrial residues by far exceeds the demand for BSF larvae feed. Further investigations are needed on the environmental impact and profitability of using biogenic residues for BSF larvae production and competing utilisation pathways as well as of using resulting BSF larvae meal as FM replacement in feed for rainbow trout. Graphical abstract – Annual technical potential of a biogenic residue-based production of black soldier fly (BSF) larvae as aquafeed for farmed rainbow trout in Germany (M = million, based on dry weight unless indicated otherwise).

Since per capita global meat utilization is predicted to increase to 40% from 2019 to 2050, global use of cultivable land in livestock, poultry, and feed production is 30%. Use of alternative protein sources as animal feed can be a solution to minimize cropland usage in conventional feed production. Commonly used protein sources in animal diets like soybean meal and fish meal are facing challenges of high demand, but the current production might not fulfill their dire need. To overcome this issue, the discovery of alternative protein sources is the need of the hour, insect meals like black soldier fly (BSF) are one of these alternative protein sources. These flies are non-infectious, bite-less, can convert the variant types of organic waste (food wastes, animal and human excreta) proficiently into rich profile biomass with reduced harmful bacteria count and do not serve as a vector in disease transmission. Based on the substrate used, the BSF larvae protein, fat and ash contents vary from 37 to 63%, 7 to 39% and 9 to 28% on dry matter basis, respectively. Previous studies have reported using BSF and its by-products as alternative protein sources in broiler diets with partial or complete replacement of conventional protein sources. In this review, a brief introduction to insect meal, BSF origin, life cycle, nutritional profile, influences on growth performance, carcass characteristics, fatty acid profile of meat, biochemical properties of blood, gut morphology and microbiota of the caecum along with its influence on laying performance of layers has been discussed in detail. Studies have concluded the partial replacement of conventional protein sources with BSF is possible, whereas complete replacement may cause poor performance due to reduced digestibility up to 62% attributable to chitin content (9.6%). Further studies to corroborate the effect of dietary BSF on growth performance, carcass characteristics, fatty acid profile of meat, and gut morphology and caecum microbiota are required to standardize the inclusion levels in feeds for higher performance of poultry.

The present study provides a macro-level framework for gender issues and their link to energy policies and environmental quality, in line with the sustainable development goals (SDG). It examines the relationship between environmental sustainability, gender equality in education, energy consumption, and sub-Saharan Africa's income by using cointegration analysis and autoregressive distributed lag (ARDL) method. The study's estimation results are consistent with the Environmental Kuznets Curve (EKC) hypothesis and policy actions suggested by eco-feminist theories in both the short-run and long-run and show that gender equality in education has positively related to environmental sustainability in sub-Saharan Africa.

Africa's information and communications technology (ICT) expansion, especially in mobile phone use, has been substantial; nonetheless, it falls behind in internet accessibility and has environmental sustainability issues, such as climate change and pollution. This study investigates the nexus between ICT penetration and environmental sustainability in Sub-Saharan Africa, using data from the World Bank and utilising a Panel Generalised Method of Moments analysis. Research demonstrates that ICT, as seen by mobile phone utilisation, positively correlates with CO2 emissions in Sub-Saharan Africa. ICT has opportunities to promote environmental sustainability via creative solutions, such as mobile money systems and energy-efficient technologies. The research highlights the need to tackle infrastructural and cost issues, advance national ICT efforts, and implement sustainable practices, such as energy-efficient hardware and life-cycle asset assessments. Policymakers are urged to use ICT as a strategic instrument to address environmental concerns and attain sustainability in the area.

The chemical composition and amino acids (AA) digestibility were determined in insect meals from mealworms, crickets, black soldier fly (BSF) larvae and BSF prepupae, and soybean meal. Six caecectomised laying hens were individually housed in metabolism cages and fed either a basal diet or one of five assay diets. Diets and hens were arranged in a 6 × 6 Latin square design with 6 subsequent periods. In each period, the laying hens were fed their respective diet for 9 d, and excreta samples were quantitatively collected twice daily from day 5 to 8. On day 9, a sterile plastic bag was attached to the cloaca of each hen to collect excreta for microbiota analysis. The AA digestibility of the insect meals and soybean meal were calculated using a linear regression approach. Crude protein (CP) concentrations in crickets and mealworms were higher than the value in soybean meal, BSF prepupae and BSF larvae. Ether extract concentrations were high in the insect meals and low in the soybean meal. The digestibility of most essential AA in soybean meal was higher (p < 0.05) than in crickets and BSF prepupae and not different from AA digestibility in mealworms and BSF larvae (except for arginine and histidine). The gene copy number of Escherichia coli in excreta from hens fed with BSF prepupae was lower (p < 0.05) than those fed with BSF larvae, whereas the gene copy number of Bacillus spp. and Clostridium spp. in excreta from hens fed with crickets was lower (p < 0.05) than those fed with BSF larvae. In conclusion, the chemical composition and AA digestibility varied among insect meals based on insect species and life stage. The high level of AA digestibility of insect meals supports the assessment that insect meals are a suitable feed component for laying hens, but differences in AA digestibility should be considered in diet formulation.

The study investigates the role of information and communication technology (ICT) and renewable energy on environmental sustainability in sub-Saharan Africa. The system generalized method of moments (GMM) was employed to estimate data of 45 sub-Saharan countries that cover the 2008 -2016 period. Result reveals that increasing ICT penetration and renewable energy use reduce CO2 emissions and improves environmental sustainability. Economic growth and population growth also mitigate CO2 emissions while education and trade openness have a neutral impact. These findings imply that increasing penetration of ICT facilities and renewable energy in the region will promote inclusive environmental sustainability. The interactive estimation of ICT variables was further considered to determine net effects and the ICT threshold that is relevant for policy implication.

Clean energy, institutional quality and environmental sustainability in sub-Saharan Africa

The aim of this study was to investigate and compare the effects of different drying methods on the physical and chemical properties of black soldier fly larvae (BSFL) to determine their potential as an alternative protein source in animal feed. The experimental design was a 2 × 3 factorial arrangement in a completely randomized design (BSFL type × drying method), with five replications. The influence of post-harvest procedures was studied, including the different BSFL types (non-defatted and defatted) and drying methods (parabola dome, hot air oven, and microwave). The results showed that the types of BSFL, drying methods, and their interaction significantly (p < 0.001) influenced the feed's physical properties; these included the brightness of color (L* 29.74-54.07; a* 0.40-5.95; b* 9.04-25.57), medium bulk density (381.54-494.58 g/L), free flow with an angle of repose (41.30-45.40°), and small particle size. They significantly (p < 0.001) influenced the nutritive value of BSFL, which contained 42-59% crude protein, 7-14% crude fiber, 9-30% ether extract, and 5035-5861 kcal/kg of energy. Overall, both BSFL types and all the drying methods resulted in a slight variation in the proximate composition. However, a microwave and a hot-air oven were considered the most suitable methods for producing BSFL powder because of the high levels of nutrients retained and the improved physical parameters when compared to a parabola dome. This characterization of the physical and chemical composition of BSFL represents a preliminary methodology that could be used to initially preprocess larvae for use as an alternative protein source in animal feed and for other applications.

Energy poverty—defined by inadequate access to reliable and affordable energy services—continues to pose a major barrier to economic development, agricultural productivity, and environmental sustainability in Sub-Saharan Africa (SSA). This study explores the complex interrelationship between energy poverty, environmental degradation, and agricultural productivity in SSA, with the aim of extracting policy insights relevant to Vietnam, a developing country facing similar rural energy access challenges. Drawing on a comprehensive literature review and empirical evidence from SSA, the study identifies that rural electrification significantly boosts agricultural productivity, while environmental degradation exerts a detrimental effect. The impact of renewable energy adoption is found to be context-dependent, with both enabling and constraining factors. Using qualitative synthesis and comparative case study analysis, the research contextualizes these findings within Vietnam’s rural development landscape. The results suggest that Vietnam can strengthen energy access and agricultural outcomes by expanding rural electrification programs, investing in decentralized renewable energy systems, and enforcing environmental regulations to prevent resource degradation. Policy recommendations include promoting public-private partnerships, supporting digital innovations for precision agriculture, and tailoring energy strategies to local socio-economic conditions. By leveraging lessons from SSA’s experiences, Vietnam can make strategic progress toward achieving energy equity and sustainable development in its rural sectors.

Review: Role of herbivores in sustainable agriculture in Sub-Saharan Africa

The use of black soldier fly larvae (BSFL) as an alternative protein source in broiler nutrition has attracted increasing interest; however, information on the effects of defrosted full-fat BSFL supplementation remains limited. This study evaluated the dose-response effects of top-dressed defrosted full-fat BSFL (10 and 20% of the previous day’s feed intake) on growth performance, gut histology, and blood metabolic markers of Ross 308 broilers. A total of 150 one-day-old male broilers were randomly allocated to three groups. The control group (CON) received a commercial corn-soybean meal-based basal diet ad libitum , while the BSFL10 and BSFL20 groups received the same diet supplemented with 10% or 20% BSFL. Growth performance and blood samples were collected on days 21 and 35. The BSFL20 group exhibited a significant increase in average daily gain (ADG) during days 22–35 and 1–35 ( ). The observed linear increase in ADG was associated with a significant linear increase in the villus height-to-crypt depth ratio in the jejunum ( ). Furthermore, BSFL20 reduced circulating triglyceride, alkaline phosphatase (ALP), and D-lactate levels ( ). There were no significant effects on the heterophil:lymphocyte (H:L) ratio, or other standard haematological parameters ( ). In conclusion, supplementation of defrosted full-fat BSFL up to 20% of the diet enhanced growth performance, improved gut histology, and induced beneficial changes in blood lipid profiles and metabolic markers in broilers, supporting the use of BSFL as a sustainable and functional feed ingredient in broiler production.

The high cost of conventional protein sources, such as soybean and fish meal, has driven the search for alternative protein sources in fish feed. This study evaluates the proximate composition of least-cost feed incorporating black soldier fly (BSF) larvae as an alternative protein source. A total of 4 kg of BSF pupae were obtained from a farm in Benin and reared in controlled conditions for 30 days. Eggs were collected from attractant traps using pineapple, vegetable, and poultry waste, then incubated until they developed into larvae. Proximate analysis revealed that BSF larvae contain 45% crude protein, making them a high-quality protein source, while adult BSF contain 24% crude protein. Moisture content was higher in adults (15%) compared to larvae (7%). Ash content was similar, with adults at 10.5% and larvae at 9.8%. Ether extract (fat content) was higher in adult BSF (21.7%) than in larvae (16.4%), indicating differences in nutritional value at different life stages. These findings suggest BSF larvae as a viable, cost-effective alternative protein source for fish feed.

Food security remains a pressing global concern, exacerbated by population growth, diminishing agricultural lands, and climate uncertainties. As the demand for high-quality protein sources like eggs, meat, and milk escalates, conventional feed ingredients face challenges in meeting the burgeoning needs of livestock production. The projected increase in poultry and pig consumption further strains the availability of protein-rich feed sources, necessitating sustainable alternatives. Insects, notably black soldier fly larvae (BSFL), offer numerous advantages, including efficiently converting organic substrates into high-quality protein, fat, minerals, and vitamins. Their rapid reproduction, minimal environmental footprint, and ability to thrive on various organic materials make them an attractive protein source. However, consumer acceptance remains a hurdle, hindering their direct consumption despite their nutritional value. Incorporating BSFL into animal diets, especially poultry and swine, demonstrates promising results regarding growth and production. This review comprehensively overviews BSFL production systems, processing techniques, and nutritional profiles. Various factors influencing BSFL growth and feed quality are discussed, highlighting the importance of optimizing breeding systems and feed formulations. Processing methods are elucidated to ensure the safety and quality of BSFL-based products. Nutritional analysis reveals BSFL as a rich source of essential amino acids, fatty acids, and minerals, making them suitable replacements for soybean meal and fish meal. Despite the economic and environmental benefits of BSFL utilization, challenges persist, including regulatory issues, consumer perceptions, and production scalability. Standardized production protocols and legislative frameworks are needed to facilitate the widespread adoption of BSFL in animal feed industries. In conclusion, integrating BSFL into animal diets presents a promising solution to address protein shortages in livestock production while promoting sustainable resource utilization.

This study aims to investigate maggot cultivation and application as an alternative feed for ornamental fish. Maggot or black soldier fly (Hermetia illucens) larva is one alternative feed that meets the requirements as a source of protein. Research Center for Ornamental Fish Cultivation (BRBIH) of the Ministry of Maritime Affairs and Fisheries has successfully developed maggot as an alternative raw material for protein sources. Maggot or black soldier fly (Hermetia illucens) larva is one alternative feed that meets the requirements as a source of protein. Besides functioning as a source of protein in fish diet, maggot can be cultivated according to the desired size. Live maggot and maggot flour as feed have been given to both ornamental fish and fish to be used for food. Thus, the use of BSF as an alternative source of protein can reduce production costs in the fishing industry without reducing its quality.

BackgroundThe most used protein sources in ruminant nutrition are considered as having negative impacts in terms of environmental sustainability and competition with human nutrition. Therefore, the investigation of alternative and sustainable feedstuffs is becoming a priority in ruminant production systems.ResultsThis trial was designed to evaluate eight full-fat insect meals (Acheta domesticus – ACD; Alphitobius diaperinus – ALD; Blatta lateralis – BL; Gryllus bimaculatus – GB; Grylloides sygillatus – GS; Hermetia illucens – HI; Musca domestica – MD; and Tenebrio molitor – TM) as potential protein and lipid sources in ruminant nutrition. Fermentation parameters and fatty acids (FA) of rumen digesta after 24-h in vitro ruminal incubation of the tested insect meals were measured and compared with those of three plant-based meals (soybean meal, rapeseed meal and sunflower meal) and fishmeal (FM). Similarly to FM, the insect meals led to a significantly lower total gas production (on average, 1.75 vs. 4.64 mmol/g dry matter—DM), methane production (on average, 0.33 vs. 0.91 mmol/g DM), volatile FA production (on average, 4.12 vs. 7.53 mmol/g DM), and in vitro organic matter disappearance (on average, 0.32 vs. 0.59 g/g) than those observed for the plant meals. The insect meals also led to lower ammonia of rumen fluid, when expressed as a proportion of total N (on average, 0.74 vs. 0.52 for the plant and insect meals, respectively), which could be an advantage provided that intestinal digestibility is high. Differences in ruminal fermentation parameters between the insect meals could be partially explained by their chitin, crude protein and ether extract contents, as well as by their FA profile. In particular, high content of polyunsaturated FA, or C12:0 (in HI), seems to partially inhibit the ruminal fermentations.ConclusionsThe tested full-fat insect meals appear to be potentially an interesting protein and lipid source for ruminants, alternative to the less sustainable and commonly used ones of plant origin. The FA profile of the rumen digesta of ACD, ALD, GB, GS and TM, being rich in n-6 polyunsaturated FA, could be interesting to improve the quality of ruminant-derived food products.