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Black soldier fly larvae wet weight in mg per prepupa or larvae (arithmetic mean ± SD), over 16 days as affected by feeding rates and feeding regimes of faecal sludge. In (A) the results represent a mean weight of 200 larvae (in three replicate treatments) fed at a rate of 100, 150, 200 and 250 mg/larva/day. (B) contains data from replicates (n=3) of 200 larvae fed at different feeding regimes: daily feeding (DF); after four days feeding (AFD); weekly feeding (WF); and lump sum feeding (LF). The equivalent feeding rate was maintained constant at 200 mg/larva/day. Days denoted by *, ** and *** indicate significant difference (ANOVA followed by Tukey post hoc tests) at P≤0.05, P≤0.01 and P≤0.001, respectively. PP = prepupa.
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The dual roles of efficient degradation and bioconversion of a wide range of organic wastes into valuable animal protein and organic fertiliser, has led to increased interest in black soldier fly (BSF) technology as a highly promising tool for sustainable waste management and alternative protein production. The current study investigated the potent...
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... this study, feeding rate of FS had a significant effect on larvae growth rate and development time (Table 1). This effect was more pronounced from day 4 onwards, with higher feeding rates resulting in faster growth ( Figure 1A). Consistent with results from other reported studies (Diener et al., 2009b;Mutafela, 2015), this observation implies that food requirements varies with time over larval growth cycle, with older larvae consuming more food than younger larvae. ...
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Background: The black soldier fly (Hermetia illucens) has emerged as a promising tool in sustainable waste management, owing to its larvae’s ability to efficiently convert organic waste into valuable biomass. Objective: This study investigates the impact of various substrate compositions on the growth, waste reduction efficiency, and bioconversion...
Citations
... Insects can survive in a wide range of environmental conditions, spawn rapidly, and consume a wide range of foodstuffs (Singh et al., 2023). Farming of insect-based conversion provides a possible step forward in supplying alternate source by reducing waste food and costly products (Nyakeri et al., 2019, Nyakeri et al., 2017Wang and Shelomi, 2017;Veldkamp et al., 2012), which is an economically save method (Barry, 2004). Only several species of insects have been introduced commercially for bio conversion of waste food, particularly by black soldier fly larvae (Hermetia illucens L.) being the most widely used (Wang and Shelomi, 2017), ace fly larvae (Arends and Wright, 1981;Wang, 1964) and Larvae of houseflies may survive on a wide range of degrading organic substrates, particularly animal waste and feed (Hogsette and Farkas, 2000). ...
The world population is predicted to surpass 10 billion by the year 2050, intensifying the burden on environmental resources and escalating the demand for food consumption. The increase in the aquaculture industry, at an average of 5.70% is attractive and crucial to the rising need for fish protein due to the valuable amino acids and its affordability. It gives about 15-16% to the total animal protein used by 2.9 billion people in low-pay and food-undersupplied nations. With the maintained expansion in the perception of health advantages , the global requirement for aquatic foods, even in established countries, is projected to rise. Aquaculture production is liable for 50% of worldwide fishery production. Conventional feeds such as fishmeal, soyabeans and plant-based feed, are the ideal protein component in aquaculture feed and pay substantially to the making expenditure in the aquaculture production. On the other hand, reducing conventional feeds supply relative to need and growing costs compromise the sustainability and growth of the aquaculture industry. The climate fluctuation and falling availability of conventional feeds have substantially impacted the cost the supply, both aquaculture and poultry industries. In contrast, significant research focused on a sustainable feed to fill up the gap. Therefore, the current review study broadly evaluated the performance of insect-based feed components, as alternative feed ingredients. The study delves into the biology, nutritional profiles, while highlighting their suitability as feed additives. An in-depth exploration of the benefits and challenges accompanying incorporating insect-based feeds into diet for animals by assuring efficiency, growth performance, and overall health for the sustainable approach.
... Six treatments were established for each substrate (crushed leaf, stem, and fruit) consisting of 100, 150, 200, 250, 300, and 350 mg substrate/larva/day according to [38], adding the last two doses; each treatment was carried out in triplicate in the same way as the control, which consisted of the Gainesville diet. The amount of substrate placed in each container was calculated for ten days of experimentation. ...
This study assessed the performance of black soldier fly larvae (BSFL) fed different tomato plant residues (fruit, leaves, and stems) at doses ranging from 100 to 350 mg/larva/day over ten days. Most doses resulted in 100% survival, except for the leaf residue at the highest dose (300 mg/larva/day), which had an 88% survival rate. Growth varied by substrate, with the highest increase observed in larvae-fed tomato fruit, followed by stems and leaves. However, no doses exceeded the control diet regarding biomass accumulation, although fruit tomatoes produced the highest wet biomass (13.71 g). Larvae-fed fruit tomatoes also showed the best performance in waste reduction index (WRI) with 7.56, substrate reduction (SR) of 75%, and a feed conversion rate (FCR) of 3.29. Furthermore, the fruit tomato was the most efficient at converting organic waste into larval biomass. This study demonstrates the potential of using tomato plant residues as a sustainable substrate for BSFL, offering an effective way to manage agricultural waste and produce valuable larval biomass.
... This suggests that a diet with 14% protein content and 18.5 MJ/kg dry matter may provide an optimal balance, fulfilling the larvae's nutritional requirements while avoiding inefficiencies from excessive protein intake. The results of this study support the importance of balancing protein intake to promote larval growth performance and biomass production while reducing nitrogen loss as indicated by previous studies [12][13][14][15][40][41][42][43][44][45]. ...
Black soldier fly, H. illucens larvae, efficiently convert low-value organic substrates into high-value products, offering solutions to global challenges in sustainable food production and biotechnology. This study investigated the impact of dietary protein levels (10%, 14%, 16%, and 20% crude protein, CP) on BSFL growth, nutrient utilization, and energy retention using isoenergetic diets (18.5 ± 0.3 MJ/kg dry matter) under commercial-scale conditions. Larvae were harvested after 8 days of feeding, with 5 replicates per treatment. Optimal growth performance and feed conversion ratios were observed in larvae fed 14% CP diet, with a quadratic relationship between dietary CP and biomass gain (p < 0.001, R² = 0.870). Ash and calcium deposition peaked in CP20-fed larvae and were lowest in CP14-fed larvae. Phosphorus and glucosamine deposition remained unaffected, while chitin deposition correlated positively with larval weight. Nitrogen and amino acid retention were highest in CP14-fed larvae but reduced in CP20-fed larvae (p < 0.001, R² = 0.573–0.902). CP10-fed larvae showed impaired growth and nitrogen deposition but increased fat deposition. These findings establish the CP14 diet as the optimal formulation for scalable BSFL production, providing critical insights into dietary protein effects on BSFL physiology and enabling the development of efficient feeding strategies for industrial-scale farming.
... BSFL growth requires an adequate supply of nutrients; hence the organic substrate selected must contain higher amounts of digestive nutrients, proteins, and carbohydrates [42]. Nutrient-deficient substrates hinder BSFL growth and performance [44,45]. Under optimal temperature conditions, BSFL can attain >75% bioconversion performance of raw organic waste into nutrient-rich frass. ...
Human population in many African countries is on upward trajectory resulting in increased waste generation. Currently, the generation of human wastes supersedes their collection, treatment and disposal. Sewage management is therefore a major problem. Available traditional sewage management systems comprise of pit latrines, soak pits, cesspools, and septic tank-soakage pits. Non-traditional, but conventional systems include constructed wetlands (CWs) and municipal wastewater treatment plants (MWWTPs). Whereas the former are largely ineffective, CWs and MWWTPs achieve significant detoxification enabling reuse of sludge and effluent water, but require considerable land sizes coupled with high investments in capital, operational and maintenance costs. Hence are less common. Pit-latrines, soak pits, cesspools and septic tank-soakage pits are locally preferred due to their lower construction and repair costs, but ineffective in sewage treatment. Herein, we present the opportunities of using black soldier fly larvae (BSFL) and microalgae as cost-effective and sustainable sewage treatment methods. A deeper understanding on the technicalities and suitability of BSFL and microalgae is provided. Microalgae are tailored for secondary wastewater treatment into high-quality effluent for reuse or discharge into the environment. Accumulated microalgae biomass is convertible into biooil, biofertiliser and biofuel. BSFL is relevant for primary sewage sludge treatment producing nutrient-rich frass as biofertilizer. The pupae are rich in protein, fats and fatty acids hence usable as animal feed. Significant gains are obtained by combining BSFL and microalgae in batch processes employing pump and treat. The process requirements, environmental and socioeconomic benefits of these methods are presented to guide in decision making.
... Diener et al. [28] found that 100 mg/larva/day of chicken feed ensured larval growth and high organic matter degradation. Similarly, Nyakeri et al. [29] compared larval growth at different feeding rates (100, 150, 200 and 250 mg/larva/day) and diets (food waste, brewer's waste, and fecal sludge), concluding that higher feeding rates significantly improved larval growth and performance with optimal results at 200 mg/larva/day of substrate. Similarly, Abduh et al. [24] tested feeding rates of 50, 75, and 100 mg of feed/larva/day, rearing BSF on a diet formulated with 0-20% of seed cake Philippine tung (Reutealis trisperma) content. ...
The large-scale insect rearing sector is expected to grow significantly in the next few years, with Hermetia illucens L. (black soldier fly, BSF) playing a pivotal role. As with traditional livestock, it is essential to improve and ensure BSF welfare. A starting point can be an adaptation of the Five Freedoms framework. Feed availability must be optimized to meet larvae nutritional needs (freedom from hunger) while maximizing substrate conversion efficiency. Similarly, rearing density needs to be optimized to ensure well-being, particularly in large-scale operations. In this study, Control (commercial laying hen feed) and Omnivorous substrates (vegetable and meat) were used as dietary regimes. In the first trial, three feeding rates were tested: 50, 100, and 200 mg feed/larva/day; in the second trial, three rearing densities were evaluated: 5, 10, and 15 larvae/cm². Performance parameters, including final larval weight, final frass biomass, growth rate, substrate reduction, feed conversion ratio, larval length, survival rate, larvae chemical composition, and process optimization, were studied. Our results show that a feeding rate of approximately 90 mg feed/larva/day in the Omnivorous diet and 175 mg feed/larva/day in the Control diet, along with a rearing density of 5 and 7.57 larvae/cm², respectively, in the Omnivorous and Control diets, produced optimal growth performances ensuring larval well-being. This outcome offers valuable insights for implementing good welfare practices in the insect farming sector and optimizing rearing management and efficiency.
... Moreover, Bosch et al. [107] recommended the use of 5-day-old larvae when proposing standardization approaches for black soldier fly larvae feeding studies. Older larvae exhibited heightened capacity to consume challenging, less assimilable feedstocks, resulting in increased food consumption compared to their younger counterparts [108]. ...
Improper disposal of organic waste leads to greenhouse gases, pollution, and health risks. Anaerobic digestion offers a sustainable solution by converting this waste into biogas and digestates, which contain valuable nutrients and stimulatory organic compounds that can be recycled to improve plant growth and support food production. Here we review the transformation of liquid and solid digestates into biostimulants by microalgal cultivation, vermicomposting, and insect-based bioconversion. These processes yield phytohormones, polysaccharides, betaines, humic substances, chitin, protein hydrolysates, and growth-promoting microbes, that enhance plant growth and resilience against environmental stresses. Due to the variability in digestate composition, we emphasize the need for optimized formulations, a deep understanding of synergistic interactions among bioactive compounds, and standardized extraction techniques to support broader applications.
... The black soldier fly (Hermetia illucens) has gained considerable attention in recent years due to its remarkable ability to convert organic waste into valuable biomass [6]. This conversion process offers significant potential for sustainable waste management and a source of high-quality protein for animal feed [7]. ...
... Understanding the factors that influence the development of Hermetia illucens larvae is essential for optimizing their use in waste management and feed production [3]. Diet composition, feeding frequency, and environmental conditions such as temperature and pH are known to significantly impact larval growth and development [6,11]. Furthermore, the balance of nutrients, particularly proteins and carbohydrates, plays a crucial role in determining the growth rates and biomass yield of the larvae [7,12]. ...
Background: The black soldier fly (Hermetia illucens) has emerged as a promising tool in sustainable waste management, owing to its larvae’s ability to efficiently convert organic waste into valuable biomass. Objective: This study investigates the impact of various substrate compositions on the growth, waste reduction efficiency, and bioconversion rate of black soldier fly (BSF) larvae (Hermetia illucens). The aim is to optimize feeding strategies to enhance the effectiveness of BSF larvae in sustainable waste management and protein production. Methods: A controlled experiment was conducted over a 20-day period, using four different substrate types: 100% sludge, 75% sludge + 25% chicken feed, 25% sludge + 75% chicken feed, and 100% chicken feed. Each treatment had three replicates with 100 larvae each. Larval growth metrics, including weight and width, were recorded bi-daily. The waste reduction efficiency and bioconversion rate were calculated based on the remaining substrate weight and larval biomass, respectively. Elemental analysis was performed to determine the impact of substrate type on the accumulation of various elements in the larvae. Results: Significant differences were observed in larval growth, waste reduction efficiency, and bioconversion rates across the different substrates. The 100% chicken feed substrate led to the highest larval growth (M = 0.0881 g/day, SD = 0.0042) and bioconversion rate (M = 7.52%, SD = 0.34), while the 100% sludge substrate achieved the highest waste reduction rate (M = 86.2%, SD = 2.15). ANOVA tests indicated that substrate composition significantly affected these outcomes (p < 0.05). Elemental analysis showed substantial variations in the concentrations of calcium, cadmium, and nickel among the substrates, with the 100% sludge substrate having the highest nickel accumulation (M = 0.2763 ppm, SD = 0.023), significantly different from the other treatments (p < 0.001). Conclusions: The results demonstrate that substrate composition is crucial for optimizing BSF larvae growth and waste reduction efficiency. Nutrient-rich substrates, such as chicken feed, significantly enhance bioconversion rates and larval biomass production, although careful consideration of elemental accumulation, especially heavy metals, is essential for safe application in animal feed.
... A higher value of bioconversion rate implies that the substrate is more consumed as opposed to a lower value (Nyakeri, 2018). In this study, use of both HFL and BSFL resulted in a higher bioconversion rate in DSE than CD probably because DSE is made up of different substrates components that enhance its nutritional value (Joly, 2018;Nyakeri et al., 2019). Low bioconversion rate for BSFL and HFL reared on CD could be associated with a higher crude fibre leading to reduced consumption. ...
... However, feeding BSFL on faecal sludge, brewers waste, banana peels and food waste resulted in a higher bioconversion rate (14.9-30.2%) than in the current study (Joly, 2018;Nyakeri et al., 2017Nyakeri et al., , 2019. Hence, different bioconversion rate could be attributed to variations in nutrients composition of the feed substrates. ...
... Nonetheless, the observed feed conversion ratio was consistent with 2.6-19.0 obtained by Nyakeri et al., (2017Nyakeri et al., ( , 2019 where BSFL was fed on human waste, agro based waste and food waste. However, feed conversion ratio of HFL observed in this study is the first to be reported. ...
Accumulation of dairy wastes and shortage of nutritious feed remain the major challenges in dairy cattle production. Such wastes may sustainably be biodegraded by black soldier fly (BSF) larvae and housefly (HF) larvae into their which ca be used as animal feed. This study was done to compare the capacity of using black soldier fly larvae (BSFL) and housefly larvae (HFL) to manage dairy wastes and use of such larvae as livestock feed. Biomass reduction rate, biomass reduction index, bioconversion rate, feed conversion ratio and nutritional profile of resultant BSF and HF prepupae raised on cow dung (CD) and dairy shed effluent (DSE) were determined. In order to ascertain whether the substrates had an effect on BSFL and HFL, analysis of variance (ANOVA) was used, and multiple mean comparisons at P≤0.05 were done using the Tukey HSD post-hoc test. Housefly larvae reared on DSE had the highest biomass reduction rate and biomass reduction index, even though HFL had a shorter development time than BSFL (P≤0.05). Housefly prepupae reared on DSE had the highest crude protein content of 60.1 % of all the HF prepupae counterparts and BSF prepupae reared on DSE and CD (P≤0.05), Hence HF prepupae could be an alternative source of animal feed. Depending on the needs and purpose, utilization of fly larvae to manage dairy waste is viable and effective option
... The rearing of insects and their acceptance as food and feed in different parts of the world is well documented [14,15,16]. This practice, if extensively carried out at commercial scales, would ease pressure on food crops [17,18] and can provide huge environmental benefits, including waste valorisation [19]. Bessa et al. [20] reported that there are over 2000 recorded insect species that have been used in entomophagy globally. ...
... Interestingly, in the surveyed literature, it was found that in most of sub-Saharan Africa, very few studies have investigated and described the characterisation of substrates in terms of food conversion ratios and waste reduction indices by BSFL. This is despite the fact that the BSFL reproduction and proliferation is highly dependent on the substrate type, which in turn affects conversion ratios and reduction indices [19]. Furthermore, because the efficiency of substrate conversion and indeed waste reduction by BSFL, and the resultant protein quality can be influenced by environmental contaminants (chemical or microbiological) [14], assessment of substrates for contaminants prior to use, is a necessity. ...
... The variety of substrates on which BSFL can be reared come from diverse sources that include agricultural-related settings, wastewater treatment plants, processing industries, waste dumps and municipal waste [19,21,37]. The substrates from these sources have site-specific contaminants that include microbiological and chemical, that may eventually be transmitted to BSFL and end up in the feed or food product [36]. ...
The emergence of climate change has rendered conventional feed sources unsustainable due in part to the rising cost of feed sources, food-feed competition and increasing ecological footprint. This is particularly the case in Africa, where most crops for feed production rely on rain-fed agriculture. Globally, agricultural production is expected to decline by 5–30% by 2050 because of climate change, and a significantly higher decline is expected in sub-Saharan Africa. As a result, insect-based feed is becoming increasingly popular as alternative protein sources, however, its safety due to microbiological, chemical and physical contaminants remains a serious potential health issue requiring urgent attention. In this review, we examined relevant literature from Africa on insect-based feed and food, focusing on the black soldier fly, Hermetia illucens , larvae (BSFL). The major focus was on the safety of BSFL through the whole value chain, from rearing substrate to processing methods and handling of the final product of feed and food. Specifically, microbiological, allergenic and chemical aspects including the potential evolution and transmission of antibiotic resistance bacteria (ARBs) and antibiotic-resistant genes (ARGs) were examined. Our findings revealed that there is inadequate research on the insect-food sector despite the wide practice of entomophagy in Africa. The results also indicated the existence of a wide variety of uncharacterised substrates from diverse sources used for rearing BSFL and that processing and handling methods practised to ensure the safety of BSFL are inadequate. The major concern was on the non-characterisation of substrates for microbiological and chemical hazards, which may facilitate the proliferation and transmission of ARBs and ARGs.
... Resource-oriented approaches have been embraced including black soldier fly, cocomposting and vermicomposting. BSF treatment has been used in the conversion of several types of organic waste such as faecal waste (Nyakeri et al., 2019), restaurant waste (Pérez-Pacheco et al., 2022) and fruits and vegetables (Hopkins et al., 2021). The larvae convert organic waste into highvalue products which can serve as an excellent source of protein in animal feed and their saprophagous feeding activity reduces the waste dry mass (residue) significantly (Lalender et al., 2013). ...
Novel technologies to convert faecal waste into valuable nutrients provide a win-win situation in enhancing the closed sanitation loop, and providing safe sanitation. In this study, laboratory-scale experiments were set to examine the applicability of the Black Soldier Fly in bioconversion of organic matter (faecal matter (FM) and kitchen waste (KW) while producing larvae biomass rich in protein and fat compounds. To determine the mass balance process, each of the feed sub-strates (500g) in triplicate and 3 grams of 6-day-old larvae (844 larvae) were introduced. The larval developmental time to 50% pupation, survival rate (SR), waste reduction rates (WR), prepupal yield, bioconversion rate (BCR), feed conversion rate (FCR), and efficiency of digested feed (ECD) were monitored in triplicate at the end of the experiments for mass balance process. Mass balance determination (triplicate) yielded average prepupal yield of 70.43±0.02g and 56.77±0.01g, with protein content per unit ranging from 32.23% to 41.26% and 20.06% to 37.13% on faecal and kitchen waste respectively. The ECD of 17.63±0.01% and 12.05±0.00%, waste reduction of 79.91% and 92.24% from faecal waste and kitchen waste respectively were obtained. From the findings , both substrates were palatable as BSFL feeds. The study findings show the potential of using BSF larvae technology to valorise faecal and kitchen waste and produce larval biomass rich in proteins and fats.
