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Summary The use of black soldier fly larvae (BSFL) to valorise different organic waste streams and the subsequent use of resulting larvae as a feedstock ingredient is increasing rapidly in several regions across the globe. The lack of knowledge about several safety issues including chemical contaminants (e.g. heavy metals) seems to affect the upscaling and commercialisation of this product. This study evaluates the safety of the BSFL against chemical contaminants including heavy metals and mycotoxins in both BSFL and frass samples reared with different food waste streams (e.g. soy waste, customised bread‐vegetable diet, food waste mixture, supermarket and childcare centre) from two commercial production facilities. The effect of larval instars and post‐harvest treatments (e.g. blanching and drying) on the safety of the BSFL was also investigated. The concentration of heavy metals was primarily influenced by the concentration in the food waste streams. The concentration was also higher in 6th instar compared to 5th instar larvae. The effect of blanching and drying have a varied effect on the concentration of heavy metals. Mycotoxins were found to be below the limit of quantification for all samples. The outcomes of this study indicated that BSFL grown on food waste streams and the resulting frass is safe against different heavy metals analysed. The findings of this study will assist the commercial BSFL manufacturers with the identification of relevant control points to ensure the chemical safety of their products. Therefore, encourage the use of different food waste streams as feedstock for rearing BSFL. [ABSTRACT FROM AUTHOR]

This study aims to develop an alternative aquafeed derived from insect meal for Lates calcarifer juveniles, with the objectives of exploring the physiological performance, biological parameters, and economic analysis of substituting fishmeal (FM) with defatted black soldier fly (Hermetia illucens) larvae (BSFL) as part of the diet of L. calcarifer juveniles. Five practical diets were formulated to include 0% (BSFL0, serves as control group), 5% (BSFL5), 10% (BSFL10), 15% (BSFL15), and 20% (BSFL20) of BSFL meal, partially or fully replacing FM, respectively. Each diet was randomly assigned to triplicate groups of 30 fish (10.70 ± 0.07 g) per tank (300 L). The fish were fed twice daily to apparent satiation. A 56‐day feeding trial was conducted to evaluate the impacts of defatted BSFL meal replacing FM on the growth performance, feed efficiency, composition analysis of fish muscle, cumulative mortality rate challenged with Vibrio parahaemolyticus, and economic returns of L. calcarifer. These results show that differences in weight gain and specific growth rate among the different treatments were statistically significant (p < 0.05), except for the absence of significant variation (p < 0.05) between BSFL0 and BSFL5, and followed by BSFL10 > BSFL0 > BSFL5 > BSFL15 > BSFL20. However, the feed conversion ratio and protein efficiency ratio showed the opposite trend as above. Although the diets experienced a decline in crude protein content and an increase in crude fat content with the increasing proportion of BSFL substituting FM, the crude protein and fat content of fish muscle were only slightly influenced. It is worth mentioning that levels of nonessential amino acids, delicious amino acids, saturated fatty acids, omega‐6, omega‐9 in BSFL10 group all showed an increase compared with the control group. After a 7‐day challenge test with V. parahaemolyticus, the cumulative mortality rates of the BSFL5 and BSFL10 groups, respectively, dropped to 5.20%, 5.28% compared to the control group's 16.88%; however, the mortality rates of BSFL15 (34.67%) and BSFL20 (41.77%) groups were found to be significantly (p < 0.05) increased. From an economic perspective, the incidence cost for each experimental group showed a trend as BSFL10 < BSFL0 < BSFL5 < BSFL15 < BSFL20, whereas the profit index in each treatment exhibited the opposite trend as above. It was concluded that low (5%) or moderate (10%) levels of BSFL substituting FM in aquaculture feed could improve the physiological performances, disease resistance, and economic returns of L. calcarifer. However, excessive substitution (>15%) leads to a negative effect. From an economic point of view, 10% inclusion of BSFL in practical diets is recommended for L. calcarifer juveniles. [ABSTRACT FROM AUTHOR]

The environmental sustainability of soybean cultivation has been questioned as it has been linked to deforestation, eutrophication, pesticide use, and carbon dioxide footprint. Agri‐industrial byproducts and black soldier fly (BSF) larvae meal are promising alternative protein sources that can be used to partly replace soybean in broiler diets. The present study aimed to investigate the effect of partial replacement of soybeans with agro‐industrial by‐products with or without the addition of BSF dried larvae meal on the meat quality, fatty acid and amino acid content, and sensory traits of breast meat of local chickens. A total of 252 one‐day‐old mixed‐sex chicks from the Anadolu‐T pure dam line were randomly assigned to 1 of 3 diets; a soybean‐based Control diet, a diet in which soybean meal was partly replaced (SPR) with brewers' dried grain, sunflower seed meal, and wheat middlings and an SPR + BSF diet in which 5% of BSF dried larva meal was added to the SPR diet. All birds were slaughtered at a commercial slaughterhouse at 55 days and breast and drumstick muscles were sampled for meat quality analysis from 18 chickens/dietary treatments. No significant effects of diets were observed for the pH24 and lightness, redness, and yellowness of breast and leg meats. Thawing loss significantly decreased and cooking loss increased in the breast meat of chickens fed the SPR + BSF compared with those fed Control and SPR diets. Diets did not affect either texture profile or consumer sensory properties of breast meat. The chickens fed the SPR + BSF had the highest total saturated fatty acid and lower polyunsaturated fatty acid content in breast meat than those fed the Control and SPR diets. The essential and nonessential amino acid content of breast meat decreased by the SPR diet compared with the SPR + BSF diet. The chickens fed SPR + BSF diet had higher values of tasty, aromatic, and umami‐related amino acids than those fed SPR and Control diets. In conclusion, the results of the present study indicated that agri‐industrial byproducts with or without BSF larvae meal could be used to partially replace soybean meal in broiler diets without affecting technological meat quality traits. The addition of BSF larvae meal to the diet along with agri‐industrial by‐products improved the amino acid content of the breast meat of chickens but reduced polyunsaturated fatty acid levels. [ABSTRACT FROM AUTHOR]

Thermal tolerance and preference are key parameters impacting agricultural production systems. In this study, the impact of larval diet on black soldier fly thermal tolerance and preference across life‐stages and sexes was examined. Larvae were fed either a low‐protein high‐carbohydrate synthetic diet (i.e., P7C35), a high‐protein low‐carbohydrate synthetic diet (i.e., P35C7), or the Gainesville diet (i.e., C) as a control and reference. Our results demonstrate that the impacts of larval diet on black soldier fly thermal tolerance and preference could be stage and sex specific. The mean heat knockdown temperatures (HKT) ranged between 46.6 and 47.9 °C. Synthetic diets resulted in greater HKT and the difference decreased form larvae (e.g., ∼1 °C) to adults (e.g., ∼0.2 °C). The mean chill‐coma recovery time (CCRT) ranged between 8.3 and 21.6 min. Not much differences were detected between diets, but CCRT became longer from larvae to adults. The mean thermal preference ranged between 13.6 and 29.5 °C. Larvae fed synthetic diets preferred much lower temperatures than the control diet. A bimodal distribution was observed for adults regardless of sex. Differences on body mass, lipid, and protein contents were detected among diets; however, more research should be done before any conclusions can be linked to their thermal traits. These findings highlight the importance of considering the ingredients and nutritional makeup of larval diets when optimizing temperature management protocols for mass production of black soldier flies. Conversely, specific diets can be developed to promote survival under extreme rearing temperatures. [ABSTRACT FROM AUTHOR]

Pathogen infection and conspecific density may considerably affect key life‐history traits of organisms. For naturally aggregating species, even low concentrations of pathogens or high larval densities may have detrimental effects. However, the detailed influence of these factors, particularly their interaction effect, is often overlooked in ecological and life‐history studies. To investigate the effects of conspecific density and pathogen infection on life‐history traits, we explored the influence of larval density (1 and 5 larvae cm−2, i.e., low and high density, respectively) on phenoloxidase (PO) activity, body mass, and development time of Hermetia illucens L. (Diptera: Stratiomyidae) larvae in the presence of two strains of the entomopathogenic fungus (EPF) Beauveria bassiana (Bals.‐Criv.) Vuill. We observed higher PO activity in EPF‐treated larvae than in the untreated control and a pronounced difference in PO activity between the two EPF‐strain treatments. Larvae reared at high density and treated with EPF showed higher PO activity than untreated larvae at low density. The EPF‐treated larvae and larvae reared at high density had longer larval periods than untreated larvae and larvae reared at low density, respectively. Larvae reared at high density also achieved reduced prepupal and pupal masses compared to conspecifics at low density. Interestingly, untreated larvae only achieved higher prepupal and pupal masses at low density, whereas at high density, the pattern was reversed (treated individuals had higher pupal masses). Overall, our results demonstrate that high density and fungal pathogens both induce a higher immune response compared to low density and pathogen‐free environments, but this comes with a cost of a longer larval period and reduced body mass. [ABSTRACT FROM AUTHOR]

The black soldier fly, Hermetia illucens, comes with big promises for industrial purposes since its larvae feed polyphagously on a broad spectrum of organic substrates. However, research focusing on adult flies is scarce, which is inconsistent with their reproductive relevance within the rearing cycle. In particular, directed oviposition is a challenge in artificial systems. Currently, decomposing organic matter is commonly used as oviposition substrate, which has extensive potential for improvement in view of the lack of standardization and the risk of microbial contamination. Here, we identified three fatty acids and one fatty acid methyl ester derived from the surface of old oviposition sites and targeted to elucidate their effect on preference behavior and oviposition site selection using Y‐olfactometry and prepared oviposition sites, respectively. Exposure to tetradecanoic acid attracted gravid females and stimulated oviposition most strongly, while decanoic acid demonstrated a repulsive effect. Females kept in mixed‐sex populations were attracted by tetradecanoic acid, resulting in a higher egg mass found in the compound box (3.0–11.4 fold), a ≥ 2.3 fold reduction of nonspecifically deposited eggs, and the highest total egg mass. Conversely, decanoic and dodecanoic acid caused females to lay a greater proportion of eggs nonspecifically outside both boxes. Our data suggest that fatty acids, especially tetradecanoic acid, are important cues for oviposition site selection in black soldier flies. In order to achieve a directed oviposition behavior, the role of further short‐ and long‐chain fatty acids as attractants should be examined. [ABSTRACT FROM AUTHOR]

Projected growth in insect production as alternative feedstuffs will yield novel by‐products that are potentially valuable for aquafeed applications. We analyzed the nutrient composition of three by‐products occurring from black soldier fly larvae production (exuvia, cocoon, imago) and the bioavailability of key nutrients for Pacific Whiteleg shrimp (Litopenaeus vannamei). Protein accounted for 317 g kg−1 in exuviae, 433 g kg−1 in cocoons, and up to 521 g kg−1 in adult flies (imagines). Considerable amounts of essential amino acids were detected in imago meal, which significantly matched the ideal dietary amino acid composition for penaeid shrimp (r2 = 0.66, p = 0.0076). Exuviae and cocoons contained moderate amounts of lipids (64–140 g kg−1), while imagines comprised 356 g kg−1 total lipid. Saturated fatty acids predominated in all insect materials (47%–83% of total fatty acids). Chitin concentration was highest in cocoons and exuviae (154 and 139 g kg−1) and low in imagines (51 g kg−1). A feeding trial with shrimp, L vannamei, revealed apparent digestibility coefficients of 20%–59% for protein, 24%–54% for energy, 25%–49% for carbon, and 27%–68% for copper. Defatting of imago meal increased the digestibility of protein, energy, and carbon by 77%, 64%, and 61%, respectively. Defatted imago meal can serve as a protein supplement for shrimp diets. [ABSTRACT FROM AUTHOR]

The weaning phase in piglets causes significant physiological stress, disrupts intestinal integrity and reduces productivity, necessitating strategies to improve intestinal health and nutrient absorption. While current research highlights the role of diet in mitigating these adverse effects, identifying effective dietary supplements remains a challenge. This study evaluated the effects of Hermetia illucens (HI) larvae meal and astaxanthin (AST) on the intestinal histology of weaned piglets. In a controlled experiment, 48 weaned piglets were divided into six groups and received varying levels of HI larval meal (2.5% and 5%) and AST in their diets. The methodology involved comprehensive histological examinations of the small intestine, assessing absorption area, villi elongation, crypt depth, goblet cells, enterocytes and expression of ileal tight junction (TJ) proteins. The study found that HI larval meal significantly improved nutrient absorption in the jejunum and ileum (p < 0.001), thereby enhancing feed conversion. AST supplementation increased the number of enterocytes (p < 0.001). Both HI larval meal and AST positively affected intestinal morphology and function, increasing muscularis muscle mass and villi elongation (p < 0.001 and p < 0.05, respectively). The 2.5% HI meal improved the villi length to crypt depth ratio and slightly increased the goblet cell count (both p < 0.05). Ki‐67 antibody analysis showed increased cell proliferation in the duodenal and jejunal crypts, particularly with the 2.5% HI meal (p < 0.001). Insect meal did not affect TJ protein expression, indicating that it had no effect on intestinal permeability. These findings suggest that HI larval meal and AST can enhance the intestinal wellness and productivity of weaned piglets. [ABSTRACT FROM AUTHOR]

Black soldier fly larva (BSFL), Hermetia illucens (L.) (Diptera: Stratiomyidae), presents an attractive waste management solution that not only addresses the issue of waste but also generates alternative proteins and fats. Substrate quality and pre‐treatment by fermentation may play a crucial role in waste reduction efficiency and larval quality. The aim of this study was to investigate the growth performance, waste reduction efficiency and nutritional composition of BSFL rearing using different ratios of coconut endosperm (CE) and soybean curd residue (SC) with pre‐treatment by self‐fermentation (F), fermentation with baker's yeast (Y) and without pre‐treatment (C). Seven‐day‐old larvae were randomly separated into 15 experimental groups with three replicates. The experiment ended when the prepupae appeared. Based on the results, the larvae fed a diet with a high percentage of fresh SC exhibited the highest weight and growth rate, whereas the shortest development time was observed in larvae reared on Y. Pre‐treatment of the substrate with fermentation proved effective in waste reduction. The nutritional composition of the larvae showed that the highest crude protein was produced in larva reared on fresh 100% SC, and the highest ether extract was found when fed CE at 100% with pre‐treatment with F or Y. In conclusion, it is recommended to employ a fresh diet with a high SC content to optimise protein production, whereas a high level of CE with F or Y may be performed to obtain a high ether extract content. However, incorporating yeast fermentation with an SC content exceeding 25% provided high efficiency in waste reduction. Therefore, the selection of the ratio between CE and SC and of pre‐treatment techniques depends on the producer's objective. [ABSTRACT FROM AUTHOR]

The black soldier fly (BSF), Hermetia illucens, has the ability to efficiently bioremediate organic waste into usable bio‐compounds. Understanding the impact of domestication and mass rearing on fitness and production traits is therefore important for sustainable production. This study aimed to assess patterns of genomic diversity and its association to phenotypic development across early generations of mass rearing under two selection strategies: selection for greater larval mass (SEL lines) and no direct artificial selection (NS lines). Genome‐wide single nucleotide polymorphism (SNP) data were generated using 2bRAD sequencing, while phenotypic traits relating to production and population fitness were measured. Declining patterns of genomic diversity were observed across three generations of captive breeding, with the lowest diversity recorded for the F3 generation of both selection lines, most likely due to founder effects. The SEL cohort displayed statistically significantly greater larval weight com the NS lines with pronounced genetic and phenotypic directional changes across generations. Furthermore, lower genetic and phenotypic diversity, particularly for fitness traits, were evident for SEL lines, illustrating the trade‐off between selecting for mass and the resulting decline in population fitness. SNP‐based heritability was significant for growth, but was low or non‐significant for fitness traits. Genotype–phenotype correlations were observed for traits, but individual locus effect sizes where small and very few of these loci demonstrated a signature for selection. Pronounced genetic drift, due to small effective population sizes, is likely overshadowing the impacts of selection on genomic diversity and consequently phenotypic development. The results hold particular relevance for genetic management and selective breeding for BSF in future. [ABSTRACT FROM AUTHOR]

Summary: This study aims to identify novel antioxidant peptides within black soldier fly larvae protein (BSFLP) using simulated gastrointestinal processes, LC–MS/MS analysis, and virtual screening. Two peptides, PFCPK and ADFW, exhibited significant antioxidant properties in both in vitro radical scavenging experiments and in vivo evaluations using zebrafish embryos induced with 2,2′‐azobis(2‐methylpropionamidine) dihydrochloride. Treatment with 25 μg mL−1 of PFCPK or ADFW significantly (P < 0.05) enhanced zebrafish embryo survival, reduced abnormal heartbeats and lowered ROS generation rate by 62.98% and 83.44%, lipid peroxidation by 52.54% and 68.35%, and cell death rate by 86.92% and 97.54%, respectively. Moreover, they restored antioxidant enzyme activities and MDA levels to near‐normal values, demonstrating significant therapeutic effects. The observed antioxidant effects may potentially be linked to the modulation of the Keap1/Nrf2 pathway. This study provides valuable insights for developing novel natural antioxidants and maximising the high‐value applications of BSFLP. [ABSTRACT FROM AUTHOR]

Organic wastes, including cheese whey, are generated in greater quantities each year, which require management that has economic and social implications. Current treatments of cheese whey do not allow for its complete degradation or utilization. In this context, black soldier fly larvae (BSFL) promise to degrade a variety of wastes while generating and accumulating value‐added products such as protein, fat that can be transformed into biodiesel, and fertilizer can be obtained from their residues. In this work, the aim was to evaluate the cultivation of BSFL as a biological treatment for the revaluation process of cheese whey, as well as the composition of the larvae and residue (FRASS) obtained for the subsequent extraction of value‐added products such as fat or protein. It was observed that cheese whey did not affect the growth of the larvae, on the contrary, it increased it (final weight of = 0.252 ± 0.003 g). The larvae biomass was composed of mainly of lipids (42.48 ± 1.26% dry matter) and protein (34.98 ± 0.72% dry matter). A fatty acid profile was also performed, which confirms that, due to their composition (Saturated fatty acids = 262.91 ± 34.81 mg/g; monounsaturated fatty acids = 85.29 ± 19.64 mg/g; polyunsaturated fatty acids = 63.68 ± 11.33 mg/g), these accumulated lipids can be extracted for biodiesel production. This is the first approach to the treatment and utilization of cheese whey through insects. [ABSTRACT FROM AUTHOR]

Collective behaviors efficiently impart benefits to a diversity of species ranging from bacteria to humans. Fly larvae tend to cluster and form coordinated digging groups under crowded conditions, yet understanding the rules governing this behavior is in its infancy. We primarily took advantage of the Drosophila model to investigate cooperative foraging behavior. Here, we report that Drosophila‐related species and the black soldier fly have evolved a conserved strategy of cluster digging in food foraging. Subsequently, we investigated relative factors, including larval stage, population density, and food stiffness and quality, that affect the cluster digging behavior. Remarkably, oxygen supply through the posterior breathing spiracles is necessary for the organization of digging clusters. More importantly, we theoretically devise a mathematical model to accurately calculate how the cluster digging behavior expands food resources by diving depth, cross‐section area, and food volume. We found that cluster digging behavior approximately increases 2.2 fold depth, 1.7‐fold cross‐section area, and 1.9 fold volume than control groups, respectively. Amplification of food sources significantly facilitates survival, larval development, and reproductive success of Drosophila challenged with competition for limited food resources, thereby conferring trophic benefits to fitness in insects. Overall, our findings highlight that the cluster digging behavior is a pivotal behavior for their adaptation to food scarcity, advancing a better understanding of how this cooperative behavior confers fitness benefits in the animal kingdom. [ABSTRACT FROM AUTHOR]

Black soldier fly larvae (Hermetia illucens) receive growing interest as a potential alternative animal feed source. These insects may be exposed to insecticide residues in the rearing substrate. This study aimed to investigate the effects of six different pyrethroid and organophosphate insecticides on this insect species' performance. The toxicity of two "model" substances for each of these classes (cypermethrin; pirimiphos‐methyl) was quantified, with and without the synergist piperonyl butoxide (PBO). Critical effect doses corresponding to 10% yield (CED10) for cypermethrin (0.4 mg/kg) and pirimiphos‐methyl (4.8 mg/kg) were determined. The addition of PBO to cypermethrin enhanced its relative potency with a factor 2.6. These data were compared against the relative toxicity of two analogue substances in each class (permethrin, deltamethrin; chlorpyrifos‐methyl, malathion). Results suggest that exposure to concentrations complying with legal limits can cause significant reductions in yield. Exposure to multiple substances at lower concentrations resulted in negative additive and synergistic effects. Of the tested substances, deltamethrin was most toxic, causing 94% yield at 0.5 mg/kg. Analytical results suggested that transfer of tested substances to the larval biomass was substance‐ and concentration‐specific, but appeared to be correlated to reduced yields and the presence of PBO. Transfer of organophosphates was overall low (<2%), but ranged from 8% to 75% for pyrethroids. Due to very low limits in insect biomass (∼0.01 mg/kg), high transfer may result in noncompliance. It is recommended that rearing companies implement lower contractual thresholds, and that policymakers consider adjusting legally allowed maximum residue levels in insect feed. [ABSTRACT FROM AUTHOR]

Background and Aims: Natural products are widely used in the pharmaceutical and cosmetics industries due to their high‐value bioactive compounds, which make for "greener" and more environmentally friendly ingredients. These natural compounds are also considered a safer alternative to antibiotics, which may result in antibiotic resistance as well as unfavorable side effects. The development of cosmeceuticals, which combine the cosmetic and pharmaceutical fields to create skincare products with therapeutic value, has increased the demand for unique natural resources. The objective of this review is to discuss the biological properties of extracts derived from larvae of the black soldier fly (BSF; Hermetia illucens), the appropriate extraction methods, and the potential of this insect as a novel active ingredient in the formulation of new cosmeceutical products. This review also addresses the biological actions of compounds originating from the BSF, and the possible association between the diets of BSF larvae and their subsequent bioactive composition. Methods: A literature search was conducted using PubMed and Google Scholar to identify and evaluate the various biological properties of the BSF. Results: One such natural resource that may be useful in the cosmeceutical field is the BSF, a versatile insect with numerous potential applications due to its nutrient content and scavenging behavior. Previous research has also shown that the BSF has several biological properties, including antimicrobial, antioxidant, anti‐inflammatory, and wound healing effects. Conclusion: Given the range of biological activities and metabolites possessed by the BSF, this insect may have the cosmeceutical potential to treat a number of skin pathologies. [ABSTRACT FROM AUTHOR]

Fungal resistance and the environmental degradation posed by conventional fungicides necessitate the need to develop new antifungal agents that can inhibit fungal growth. This study sought to prepare biofungicides by leveraging on the antifungal activity of copper‐metal organic framework (Cu‐MOF) and dialdehyde chitosan (Cs) isolated from black soldier flies (BSF). Cs were oxidized using potassium periodate to obtain dialdehyde Cs (OCs) and thereafter, Cu‐MOF was loaded resulting in Cu‐MOF‐OCs. Fourier Transform Infrared spectrophotometer (FT‐IR) and powder X‐ray diffraction (XRD) confirmed the presence of carbonyl functional groups in OCs and sharp intense peaks associated with Cu that interacted. The changes in surface morphology and the presence of Cu in the MOFs as obtained with Scanning Electron Microscope‐ Energy Dispersive X‐ray (SEM‐EDX), indicated the successful loading of Cu‐MOF on the oxidized Cs. Thermogravimetric analysis (TGA) showed a loss of approximately 31.51 % of the loaded OCs and 40.72 % framework around ∼200 to ∼300 °C and ∼410 to ∼475 °C respectively. The antifungal activity of OCs, Cu‐MOF, and Cu‐MOF‐OCs against Aspergillus brasiliensis and Candida albicans was performed using the plate count method and the results suggested that MOF modulated the antifungal activity exerted by the OCs. [ABSTRACT FROM AUTHOR]

Frass, a byproduct of insect rearing, has become popular for its potential use in sustainable agriculture. The rapid growth of insect production results in an increased frass output. This study examined the effects of frass as soil amendment on plant growth and resistance to insect herbivory. In greenhouse experiments, Brassica rapa L. (Brassicaceae), was grown in unamended soil (NoFrass; control) or soil amended with frass (2 g kg−1) from larvae of black soldier fly (BSFF), Hermetia illucens L. (Diptera: Stratiomyidae), or yellow mealworm (MWF), Tenebrio molitor L. (Coleoptera: Tenebrionidae). Frass was applied as raw, incubated, or composted frass before seed germination. Plant growth and performance were measured of larvae of root‐feeding Delia radicum L. (Diptera: Anthomyiidae) and shoot‐feeding Plutella xylostella L. (Lepidoptera: Plutellidae). Initially, raw BSFF and MWF reduced the growth of B. rapa and resulted in a smaller leaf area than NoFrass. However, over time, a notable trend emerged. Whereas the difference in leaf area between MWF and NoFrass disappeared, BSFF consistently resulted in a smaller leaf area than MWF and NoFrass. Raw BSFF reduced D. radicum larval survival and pupal biomass and larval survival of P. xylostella. In contrast, raw MWF increased larval survival and biomass of D. radicum and the survival of P. xylostella larvae. Interestingly, incubation of frass in the soil for 16 days before seed germination removed plant growth inhibition and increased plant leaf area, especially for MWF compared to NoFrass. In addition, composting MWF increased leaf growth. Therefore, frass may be used as a sustainable and natural alternative to conventional organic fertilisers, promoting plant growth and enhancing resistance to herbivory. Our results indicate that soil amendment with raw BSFF may negatively impact herbivore performance, whereas raw MWF may enhance herbivore performance. [ABSTRACT FROM AUTHOR]

The yellow gene family plays a crucial role in insect pigmentation. It has potential for use as a visible marker gene in genetic manipulation and transgenic engineering in several model and non‐model insects. Sadly, yellow genes have rarely been identified in Stratiomyidae species and the functions of yellow genes are relatively unknown. In the present study, we first manually annotated and curated 10 yellow genes in the black soldier fly (BSF), Hermetia illucens (Stratiomyidae). Then, the conserved amino acids in the major royal jelly proteins (MRJPs) domain, structural architecture and phylogenetic relationship of yellow genes in BSF were analyzed. We found that the BSF yellow‐y, yellow‐c and yellow‐f genes are expressed at all developmental stages, especially in the prepupal stage. Using the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR‐associated protein 9 (Cas9) system, we successfully disrupted yellow‐y, yellow‐c and yellow‐f in the BSF. Consequently, the mutation of yellow‐y clearly resulted in a pale‐yellow body color in prepupae, pupae and adults, instead of the typical black body color of the wild type. However, the mutation of yellow‐c or yellow‐f genes did not result in any change in color of the insects, when compared with the wild type. Our study indicates that the BSF yellow‐y gene plays a role in body pigmentation, providing an optimal marker gene for the genetic manipulation of BSF. [ABSTRACT FROM AUTHOR]

Waste treatment using black soldier fly (BSF; Hermetia illucens L.) larvae is an emerging technology that reduces livestock manure disposal. This study aimed to evaluate the effect of different growth stage BSF larvae on the decomposition potential (Experiment 1) and characteristics (Experiment 2) of pig manure. BSF larval instars were randomly divided in three groups according to their developmental stage, with three replicates per group, using a randomized block design. Each treatment group consisted of 1 kg of 2nd, 3rd, or 4th instar BSF larvae added in 10 kg of pig manure (Group 1, 2, or 3, respectively). In Experiment 1, 2nd and 3rd instar BSF larvae treatments resulted in greater decomposition levels of pig manure compared with 4th instar BSF larvae groups. In Experiment 2, BSF larvae improved the nutrient content of manure, leading to an increase in the total nitrogen levels and a decrease in total carbon content and C:N ratio, rendering it suitable for use as an organic fertilizer. In addition, the increased N levels of treated BSF manure were not related to lower pH levels. BSF larvae can greatly reduce ADF and NDF pig manure contents as a result of the larvae's waste reduction potential. Overall, BSF 3rd instar larvae have proven to be a useful tool for the sustainable management of pig manure by strongly increasing its decomposition ability and can be an organic fertilizer for agricultural purposes that reduce ADF and NDF contents through composting. [ABSTRACT FROM AUTHOR]

The inadequate disposal of organic waste generated in insect biofactories breeding biological agents may become a potential environmental problem. The use of Hermetia illucens (Diptera: Stratiomyidae) may play an important role in the circular economy of this process, transforming waste into high‐quality biomass. Therefore, this work aims to analyse the degradation of organic residues of Ephestia kuehniella (Lepidoptera: Pyralidae) production using the black soldier fly. Four types of waste from the moth breeding process were evaluated: residues of the meal diet when moth larvae were in the last instar; residues of the meal diet when completing the cycle; residues formed by webs in the pupation process mixed with residual exoskeleton, and residues of dead adults. These residues were tested in isolation and in mixtures of 50%, using as control a standard diet composed of chicken feed. Survival rate, development time, emerged adults, weight, size, residue reduction, and bioconversion were evaluated. The residue used in diets affected the total development time of H. illucens. The mean number of survivors differed from 87% to 74% for larvae that reached the pre‐pupal stage. The viability of pre‐pupae to adult stage ranged from 54% to 6% for residue treatments and 97% for the control. Differences in the growth and weight gain of larvae were significantly different. The rate of residue reduction from 54% to 80% and bioconversion into larval biomass were satisfactory. However, regarding adult emergence, the numbers show variations, indicating that certain residues are not suitable for the maintenance of fly breeding. [ABSTRACT FROM AUTHOR]

An editorial is presented which expresses the views on the progress and future direction of the journal "Aquaculture, Fish and Fisheries" as it supports the blue revolution. Topics include the journal's achievements in promoting global research on aquaculture and fisheries, the introduction of new initiatives for early-career scientists, and the focus on addressing challenges like climate change, pollution, and sustainability in aquatic ecosystems.

Societal Impact Statement: Refining circular multitrophic food production methods, which integrate plant, fish, and insect outputs, is imperative for environmental sustainability. Our findings suggest that the right protein choices in fish feed, like black soldier fly meal and poultry meal, can notably enhance the nutrient profile of fish waste water. This, in turn, is conducive for hydroponic cultivation, enhancing the nutritional attributes of plants like basil and lettuce. As we reduce environmental impact and optimize resource use, it is evident that our food ecosystems are deeply intertwined. Harnessing these synergies could redefine our approach to food production, paving the way for a more sustainable global future. Summary: Optimization of nutrient use efficiencies in circular multitrophic food production systems (i.e., plant, fish, and insect production) is crucial for sustainability. This study tested how protein ingredient choice in fish feed influences the plant nutritional value of the fish waste water when used for hydroponic crop production.Waste water samples were obtained from recirculating aquaculture systems (RAS) in which Nile tilapia (Oreochromis niloticus) were fed different single protein source diets—black soldier fly meal (BSFM), poultry by‐product meal (PM), poultry blood meal (PBM), and fish meal. Water was analyzed for plant nutrients and used for lettuce and basil cultivation to evaluate their suitability for hydroponic crop production—viz. yield, mineral nutrient, and selected secondary metabolite levels.BSFM RAS water had the highest concentrations of K, Mg, and micronutrients (Cu, Mn, Mo, Zn) of the RAS waters, whereas PM RAS water contained the highest P concentration and had a mean pH of 6.5 closer to the optimum pH for hydroponic plants. These RAS waters consequently lead to the highest yields in basil and lettuce indicating the importance of the aforementioned factors.From a plant production perspective, BSFM appears promising as a protein source in fish feeds for aquaponics. Usage of RAS waters for plant production helps reduce (i) environmental impact of RAS water and (ii) resource input in plant production. Longer term RAS trials should be conducted to determine the maximum nutrient concentrations achievable during fish production with diets including BSFM as the main protein source. [ABSTRACT FROM AUTHOR]

BACKGROUND: The demand for protein obtained from animal sources is growing rapidly, as is the necessity for sustainable animal feeds. The use of black soldier fly larvae (BSFL) reared on organic side streams as sustainable animal feed has been receiving attention lately. This study assessed the ability of near‐infrared spectroscopy (NIRS) combined with chemometrics to evaluate the nutritional profile of BSFL instars (fifth and sixth) and frass obtained from two different diets, namely soy waste and customised bread‐vegetable diet. Partial least squares (PLS) regression with leave one out cross‐validation was used to develop models between the NIR spectral data and the reference analytical methods. RESULTS: Calibration models with good [coefficient of determination in calibration (Rcal2): 0.90; ratio of performance to deviation (RPD) value: 3.6] and moderate (Rcal2: 0.76; RPD value: 2.1) prediction accuracy was observed for acid detergent fibre (ADF) and total carbon (TC), respectively. However, calibration models with moderate accuracy were observed for the prediction of crude protein (CP) (Rcal2: 0.63; RPD value: 1.4), crude fat (CF) (Rcal2: 0.70; RPD value: 1.6), neutral detergent fibre (NDF) (Rcal2: 0.60; RPD value: 1.6), starch (Rcal2: 0.52; RPD value: 1.4), and sugars (Rcal2: 0.52; RPD value: 1.4) owing to the narrow or uneven distribution of data over the range evaluated. CONCLUSION: The near‐infrared (NIR) calibration models showed a good to moderate prediction accuracy for the prediction of ADF and TC content for two different BSFL instars and frass reared on two different diets. However, calibration models developed for predicting CP, CF, starch, sugars and NDF resulted in models with limited prediction accuracy. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: The black soldier fly (BSF) offers a potential solution to address shortages of feed and food sources; however, selecting effective rearing substrates remains a major hurdle in BSF farming. In an urban area like Singapore, current practice is based on rearing BSF on homogeneous waste streams (e.g., spent brewery grains or okara) because heterogeneous food wastes (e.g., mixed kitchen/canteen waste or surplus cooked food) present several operational challenges with respect to the standardization of development, nutritional content, and harvesting. RESULTS: In this study, we compared two genetic strains of BSF larvae (wild‐type and laboratory‐adapted line) in a bioconversion experiment with diverse types of food waste (homogeneous/heterogeneous; plant/meat) and we quantified the phenotypic plasticity. Our results demonstrate different plasticity in bioconversion performance, larval growth and larval nutrition between the two BSF lines. This difference may be attributed to the selective breeding the laboratory‐adapted line has experienced. Notably, larval lipid content displayed little to no genetic variation for plasticity compared with larval protein and carbohydrate content. Despite variation in larval development, heterogeneous food wastes can produce better performance in bioconversion, larval growth, and larval nutrient content than homogeneous food waste. All‐meat diets result in high larvae mortality but larval survival could be rescued by mixing meat with plant‐based food wastes. CONCLUSION: Overall, we suggest using mixed meals for BSF larvae feeding. Targeted breeding may be a promising strategy for the BSF industry but it is important to consider the selection effects on plasticity in larval nutrition carefully. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

With the increasing demand for portable electronic devices and the shortage of conventional energy resources, energy harvesting from natural resources has gained much attention. Herein, they proposed a black soldier fly (BSF) derived chitin biofilm to fabricate high‐performance triboelectric and piezoelectric nanogenerators. The physiochemical characterizations of the chitin biofilm are demonstrated by the presence of the hydroxyl group, alpha chitin, and beta chitin, which are responsible for the remarkable tribopositive, and piezoelectric function of the chitin derived from BSF. The electrical performance of the proposed work, such as voltage, current, and instantaneous power from BSF/PTFE‐based triboelectric nanogenerator (TENG) are exhibited at 121 V, 15 µA, and 217.8 µW, respectively. Ag/BSF/Ag piezoelectric nanogenerator (PENG) is generated 18 V voltage, 2.2 µA current, and 5 µW instantaneous power. Moreover, the proposed TENG and PENG devices demonstrate the ability to charge the dielectric capacitors and drive low‐power electronic devices like LEDs and a calculator. The proposed results suggested that chitin is a superior biomaterial for developing sustainable energy harvesting devices. [ABSTRACT FROM AUTHOR]

The reproductive biology of the black soldier fly (BSF), Hermetia illucens (L.) (Diptera: Stratiomyidae), was investigated in males and females with a focus on how sperm is handled by males before – and by females after – copulation. As this insect has great economic importance for protein production from agri‐food wastes, its reproduction needs to be precisely known. A detailed description of male and female reproductive organs was made, and sperm were counted in male and female storage organs. Measures of testis and sperm counts were performed in males of various ages and their dynamics was compared to the ovaries of females. Both male and female tracts were long, and consisted of various successive parts. In males, testes fill the vas deferens with mature sperm, that are tangled as 'windrows', and sperm pass successively through a 'studded pipe' and three phallic 'wands' before being transferred to females. In virgin males, mean (± SEM) sperm number increased from approximately 9700 (± 1400, n = 5) to 39600 (± 3470, n = 13) in 20 days, and testes gradually decreased in size, indicating continuous spermatogenesis. Sperm cells are long, more than 3 mm. During copulation, sperm are deposited by phallic 'wands' at the base of each spermatheca in a smooth tube followed by a 'fishnet canal' at the top of which they accumulate before complete storage. They then pass through a ringed canal, an elbow, and a rigid rod strewn with glands, before reaching the spermathecal reservoir. Females store approximately 680 spermatozoa after one mating in each spermathecal reservoir. Such complex sperm storage organs of females may indicate strong female post‐mating selection, and reflect competition for long and numerous sperm in this species, in which female multiple matings are suspected. Besides its economical interest, BSF is an appealing model for further investigations on sexual selection. [ABSTRACT FROM AUTHOR]

Replacing fishmeal, a finite resource with high market demand, in the diet of carnivorous rainbow trout with proteins from alternative sources may be a challenge for these fish. Therefore, this study investigated whether replacing fishmeal with protein derived from Hermetia illucens or Arthrospira platensis could promote disease susceptibility in local trout populations with different growth performance. This was assessed in vitro by measuring susceptibility to infection with the viral haemorrhagic septicaemia virus (VHSV) or the bacterium Yersinia ruckeri. Analysis of fin tissue explants and primary cell cultures from scales from the three trout populations infected in vitro with VHSV and gill explants infected with Y. ruckeri showed no significant differences in virus replication or bacterial counts. Evaluation of the virucidal or bactericidal effect of skin mucus showed a significant reduction in viral load and bacterial count for all samples with mucus addition, but no significant difference was observed between the experimental groups. This study documents no apparent impairment of innate immune mechanisms in the skin and gills of trout after feeding a diet replacing fishmeal with Arthrospira or Hermetia proteins. This underlines the potential of these alternative protein sources for the further development of sustainable trout aquaculture. [ABSTRACT FROM AUTHOR]

This study examined the effects of various insect species, such as those of Bombyx mori, Hermetia illucens and Tenebrio monitor, that have long been used in combination with medicinal plants and are an important alternative to modern medicine in many parts of the world. The current use of traditional pesticides from around the year 2010 and the characteristics of isolated biologically active molecules are also presented. Natural insect products were examined or isolated from ants, bees, beetles, cockroaches, termites, bees, etc. The biological activities of these natural products derived from insects include antimicrobial, antifungal, anticancer, antiviral, antioxidant and anti‐inflammatory effects. Insect additives to animal feed rarely distort the relevant physicochemical variables or sensory profile of the meat, whereas the fatty acid (FA) profile is discernibly changed. In fact, insect derivatives have great potential for future drug discovery in natural products, as well as for the production of nutritious foods for humans and for animals. It is concluded that the inoculation of insect powder in animal feeds results in the prevention and treatment of disease, enhances the growth of animals and promotes the bioactive compounds in animal‐based products. Owing to the sustainability of their breeding, large‐scale cultures of these insects seem economically viable. Insect oil and protein as well as chitin ingredients are widely used in cosmetics, and these substances are considered high‐value co‐products. The major challenges associated with their use will be linked to the development of methods for separating industrial‐derived materials. [ABSTRACT FROM AUTHOR]

Bioconversion is a biological process by which organic materials are converted into products with higher biological and commercial value. During its larval stage the black soldier fly Hermetia illucens is extremely voracious and can feed on a wide variety of organic materials. To study the impact of different fruit byproducts on the insect's growth, final larval biomass, substrate reduction, bioconversion parameters, and larval nutritional composition, 10 000 black soldier fly larvae (BSFL) were reared on 7.0 kg of one of three substrates (strawberry, tangerine, or orange) or on a standard diet as a control. The results highlight that BSFL can successfully feed and grow on each of these diets, though their development time, growth rate, and final biomass were differently impacted by the substrates, with strawberry being the most suitable. The lipid and protein contents of BSFL were similar among larvae fed on different substrates; however, major differences were detected in ash, micronutrient, fiber, fatty acid, and amino acid contents. Overall, the results indicate that fruit waste management through the BSFL bioconversion process represents a commercially promising resource for regional and national agrifood companies. Our study offers new perspectives for sustainable and environmentally friendly industrial development by which fruit byproducts or waste might be disposed of or unconventionally enhanced to create secondary products of high biological and economic value, including BSFL biomass as animal feed or, in perspective, as alternative protein source for human nutrition. [ABSTRACT FROM AUTHOR]

Sex‐determination pathways are extremely diverse. Understanding the mechanism of sex determination in insects is important for genetic manipulation of the pest population and for breeding of economically valuable insects. Although sex determination has been well characterized in the model species Drosophila melanogaster, little is known about this pathway in Stratiomyidae. In the present study, we first identified the Drosophila intersex (ix) homolog in Hermetia illucens, also known as the black soldier fly, which belongs to the Stratiomyidae family and which is an important insect for the conversion of various organic wastes. Phylogenetic analyses and multiple sequence alignment revealed that Hiix is conserved compared with Drosophila. We showed that Hiix is highly expressed in internal genitalia. Disruption of the Hiix gene using CRISPR/Cas9 resulted in female‐specific defects in external genitalia and abnormal and undersized ovaries. Taken together, our study furthers our understanding of sex determination in insects and could facilitate breeding of H. illucens. [ABSTRACT FROM AUTHOR]

However, upon extracting NMDS axes as univariate proxy variables for representing microbiome dissimilarity between larval gut samples, a significant Spearman correlation for a relationship between I Cec2 i expression and NMDS axis 1 ( = -0.769, I P i = 0.005) was found. Dear Editor, The black soldier fly (BSF) ( I Hermetia illucens i Linnaeus, 1758) is an important insect in the sustainable agriculture sector that has attracted much interest over the last few years. I Cec2 i gene regulation constitutes a plausible host-related mechanism underlying the diet-dependent differentiation of BSF larval gut communities that is associated with the abundance of specific bacterial taxa, and seemingly independent from host genetics and genetic-by-diet interactions. The BSF contains the largest number of unique antimicrobial peptide (AMP) genes amongst insects (Zhan I et al. i , [18]) and these peptides have also been advocated as alternative antibiotics, in light of growing antimicrobial resistant microorganisms (Tonk & Vilcinckas, 2017). [Extracted from the article]

Insect proteins have been proposed for human and animal food production. Safeguarding the health status of insects in mass rearing allows to obtain high‐quality products and to avoid severe economic losses due to entomopathogens. Therefore, new strategies for preserving insect health must be implemented. Modulation of the insect immune system through the diet is one such strategy. We evaluated gene expression of two antimicrobial peptides (one defensin and one cecropin) in Hermetia illucens (L.) (Diptera: Stratiomyidae) reared on different diets. Analyses were performed on prepupae and 10‐day‐old larvae reared on cereal‐ and municipal organic waste‐based diets and on only prepupae reared on a cereal‐based diet supplemented with sunflower, corn, or soybean oil. The inclusion of sunflower oil at different points in the cereal‐based diet was also evaluated. Moreover, diet‐driven differences in the inhibitory activity of the hemolymph were tested against Escherichia coli DH5α and Micrococcus yunnanensis HI55 using diffusion assays in solid media. Results showed that a municipal organic waste‐based diet produced a significant overexpression of antimicrobial peptides only in prepupae. Inclusion of vegetable oils caused an upregulation of at least one peptide, except for the corn oil. Higher expression of both genes was observed when sunflower oil was added 5 days before pupation. All hemolymph samples showed an inhibitory activity against bacteria colonies. Our results suggest that municipal organic waste‐based diet and vegetable oil‐added diet may successfully impact the immune system of H. illucens. Such alternatives may also exist for other species of economic interest. [ABSTRACT FROM AUTHOR]

Efficient gene modification in BSF has also recently been reported (Zhan I et al. i , [45]; Kou I et al. i , [17]), highlighting the possibility of revealing the functions of genes and selecting more economically beneficial strains. Dear Editor, Economic and population growth increasingly consume resources from the environment and present a major challenge regarding the management of waste. The comprehensive database BSFbase integrates multiple lines of omics data and other informative data on BSF. As modification by gene editing is an increasingly popular way of improving breeds, BSFbase provides a clustered regularly interspaced palindromic repeats (CRISPR) / CRISPR-associated protein 9 (Cas9) protocol and video protocol in "Source" with the aim of facilitating the effective application of this technology to BSF. [Extracted from the article]

Mass production of black soldier fly, Hermetia illucens (L.) (Diptera: Stratiomyidae), larvae results in massive heat generation, which impacts facility management, waste conversion, and larval production. We tested daily substrate temperatures with different population densities (i.e., 0, 500, 1000, 5000, and 10 000 larvae/pan), different population sizes (i.e., 166, 1000, and 10 000 larvae at a fixed feed ratio) and air temperatures (i.e., 20 and 30 °C) on various production parameters. Impacts of shifting larvae from 30 to 20 °C on either day 9 or 11 were also determined. Larval activity increased substrate temperatures significantly (i.e., at least 10 °C above air temperatures). Low air temperature favored growth with the higher population sizes while high temperature favored growth with low population sizes. The greatest average individual larval weights (e.g., 0.126 and 0.124 g) and feed conversion ratios (e.g., 1.92 and 2.08 g/g) were recorded for either 10 000 larvae reared at 20 °C or 100 larvae reared at 30 °C. Shifting temperatures from high (30 °C) to low (20 °C) in between (∼10‐d‐old larvae) impacted larval production weights (16% increases) and feed conversion ratios (increased 14%). Facilities should consider the impact of larval density, population size, and air temperature during black soldier fly mass production as these factors impact overall larval production. [ABSTRACT FROM AUTHOR]

The black soldier fly (BSF), Hermetia illucens (Diptera: Stratiomyidae), is an insect commonly used for the bioconversion of various organic wastes. Not only can the BSF convert organic waste into macromolecular organic substances, such as insect proteins, but it can also lessen the pollution associated with these waste products by reducing ammonia emissions, for example. In this study, we measured the effects of adding fruit fermentation broth (Fer) and commercial lactic acid bacteria fermentation broth (Em) to kitchen waste (KW), as deodorizing auxiliary substances, on the growth performance of black soldier fly larvae (BSFL), the intestinal flora structure of BSFL, the ammonia emission from the KW substrate, and the microbial community structure of the KW substrate. We found that the addition of Fer or Em increased the body weight of BSFL after 6 d of culture, increasing the growth rate by 9.96% and 7.96%, respectively. The addition of Fer not only reduced the pH of the KW substrate but also increased the relative abundance of probiotics, such as Lactobacillus, Lysinibacillus, and Vagococcus, which inhibited the growth of ammonifiers such as Bacillus, Oligella, Paenalcaligenes, Paenibacillus, Pseudogracilibacillus, and Pseudomonas, resulting in the reduction of ammonia emission in the KW substrate. Moreover, the addition of Fer or Em significantly increased the relative abundances of Bacteroides, Campylobacter, Dysgonomonas, Enterococcus, and Ignatzschineria in the gut of BSFL and increased the species diversity and richness in the KW substrate. Our findings provide a novel way to improve the conversion rate of organic waste and reduce the environmental pollution caused by BSF. [ABSTRACT FROM AUTHOR]

The black soldier fly (BSF), Hermetia illucens, is a promising insect for mitigating solid waste problems as its larvae are able to bioconvert organic waste into valuable biomass. We recently reported a high‐quality genome assembly of the BSF; analysis of this genome sequence will further the understanding of insect biology and identify genes that can be manipulated to improve efficiency of bioconversion. To enable genetic manipulation of the BSF, we have established the first transgenic methods for this economically important insect. We cloned and identified the ubiquitous actin5C promoter (Hiactin5C‐p3k) and 3 endogenous U6 promoters (HiU6:1, HiU6:2, and HiU6:3). The Hiactin5C promoter was used to drive expression of a hyperactive variant of the piggyBac transposase, which exhibited up to 6‐fold improvement in transformation rate when compared to the wild‐type transposase. Furthermore, we evaluated the 3 HiU6 promoters using this transgenic system. HiU6:1 and HiU6:2 promoters provided the highest knockdown efficiency with RNAi and are thus promising candidates for future Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) development. Overall, our findings provide valuable genetic engineering toolkits for basic research and genetic manipulation of the BSF. [ABSTRACT FROM AUTHOR]

In insects, the cell‐mediated immune response involves an active role of hemocytes in phagocytosis, nodulation, and encapsulation. Although these processes have been well documented in multiple species belonging to different insect orders, information concerning the immune response, particularly the hemocyte types and their specific function in the black soldier fly Hermetia illucens, is still limited. This is a serious gap in knowledge given the high economic relevance of H. illucens larvae in waste management strategies and considering that the saprophagous feeding habits of this dipteran species have likely shaped its immune system to efficiently respond to infections. The present study represents the first detailed characterization of black soldier fly hemocytes and provides new insights into the cell‐mediated immune response of this insect. In particular, in addition to prohemocytes, we identified five hemocyte types that mount the immune response in the larva, and analyzed their behavior, role, and morphofunctional changes in response to bacterial infection and injection of chromatographic beads. Our results demonstrate that the circulating phagocytes in black soldier fly larvae are plasmatocytes. These cells also take part in nodulation and encapsulation with granulocytes and lamellocyte‐like cells, developing a starting core for nodule/capsule formation to remove/encapsulate large bacterial aggregates/pathogens from the hemolymph, respectively. These processes are supported by the release of melanin precursors from crystal cells and likely by mobilizing nutrient reserves in newly circulating adipohemocytes, which could thus trophically support other hemocytes during the immune response. Finally, the regulation of the cell‐mediated immune response by eicosanoids was investigated. [ABSTRACT FROM AUTHOR]

Black soldier fly (BSF), Hermetia illucens (Diptera: Stratiomyidae), is a prominent insect for the bioconversion of various organic wastes. As a saprotrophic insect, the BSF inhabits microbe‐rich environments. However, the influences of the intestinal microorganisms on BSF growth and development are not very clear. In this study, the dynamics of the intestinal bacterial community of BSF larvae (BSFL) were analyzed using pyrosequencing. Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria were the most prevalent bacterial phyla in the intestines of all larval instars. The dynamic changes in bacterial community compositions among different larval instars were striking at the genus level. Klebsiella, Clostridium, Providencia, and Dysgonomonas were the relatively most abundant bacteria in the 1st‐ to 4th‐instar BSFL, respectively. Dysgonomonas and Providencia also dominated the 5th‐ and 6th‐instar larvae, at ratios of 31.1% and 47.2%, respectively. In total, 148 bacterial strains affiliated with 20 genera were isolated on different media under aerobic and anaerobic conditions. Among them, 6 bacteria, BSF1–BSF6, were selected for further study. The inoculation of the 6 isolates independently into germ‐free BSFL feeding on an artificial diet showed that all the bacteria, except BSF4, significantly promoted BSF growth and development compared with the germ‐free control. Citrobacter, Dysgonomonas, Klebsiella, Ochrobactrum, and Providencia promoted BSF development significantly by increasing the weight gains of larvae and pupae, as well as increasing the prepupae and eclosion rates. In addition, Citrobacter, Klebsiella and Providencia shortened the BSF life cycle significantly. The results illustrate the promotive effects of intestinal bacteria on BSF growth and development. [ABSTRACT FROM AUTHOR]

With the global demand for lipid compounds on the rise, concerns are growing about the environmental and economic impact of traditional lipid sources. This concern is exacerbated by the ever‐increasing demand for plant‐based lipids, which is contributing to unsustainable production practices and competition for land and food. Considering this challenge, this work aimed at exploring the potential of black soldier fly larvae (BSFL) as a low‐cost and ecofriendly source of lipid classes. A fractionation scheme consisting of a mixture of polar and nonpolar solvents at different ratios was employed to isolate the lipid classes from BSFL oil using silica gel column chromatography, which is a conventional method of chromatography. The fraction's separation efficiency was validated using thin‐layer chromatography and characterized with Fourier‐transformed infrared spectroscopy and gas chromatography flame ionization (GC‐FID). Triglycerides (30%) were found to be the most abundant component while cholesterols (0.6%) were the least abundant lipid fractions in the lipid mixture. GC‐FID in the various lipid fractions analyzed, lauric acid exhibited the highest percentage among the triglycerides (16.64%), diglycerides (19.10%), monoglycerides (22.70%), and free fatty acids (27.65%) fractions. The fractionation scheme proposed achieves high efficiency in separating and recovering different lipid classes extracted from the BSFL. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the metabolic performance, in terms of specific rates of growth and feed assimilation, as well as the cost of growth and maintenance of black soldier fly larvae, BSF, Hermetia illucens on brewery waste, a potential worldwide available resource for industrial scale insect production. Brewery waste lacks starch and thus has a nutritional profile substantially different from chicken feed, which is a well‐established and excellent starchy food source for BSF larvae. It is therefore interesting to gain insight into how BSF larvae perform on brewery waste. Larvae of the BSF were reared on chicken feed, on brewery waste and on mixtures of the two. Measurements of the weight of the larvae and their respiratory CO2 production were used to estimate metabolic performance on daily basis. The BSF larvae grew on all the substrates. They reached the highest weight on chicken feed, but their specific growth and feed assimilation rates were highest on the mixed substrates, in which the larvae also reached their maximal weight in the shortest time. Substrate‐dependent costs of growth were not observed while maintenance rates tended to be only slightly lower on the mixed substrates. Overall, the BSF larvae converted the low‐starch brewery waste and the starchy chicken feed into larval biomass about equally efficiently, although brewery waste led to smaller larvae and mixing of the two substrates enhanced feed assimilation and growth. Brewery waste seems thus a suitable resource for BSF larvae, comparable with chicken feed, with respect to their metabolic performance. [ABSTRACT FROM AUTHOR]

The black soldier fly Hermetia illucens Linnaeus (Diptera: Stratiomyidae; BSF) is gaining interest as an alternative protein ingredient for livestock feed. Larval aggregation behaviour occurs commonly in larvae of various dipteran species. However, the cues initiating aggregation behaviour and its occurrence in subsequent larval instars are still unknown in BSF larvae. Here, we focus on understanding the attraction of larvae to cues left behind in the substrate by conspecific larvae. We developed a dual‐choice test in the dark and examined the preference behaviour of different instars with the use of video recordings. Larval choices were identified based on first substrate contact, cumulative number of substrate contacts, entry of the substrate and number of larvae present in a substrate over time. Our results demonstrate that BSF larvae discriminated between similar substrates with or without cues released by conspecifics, with a strong preference for previously colonised substrates. Our results also showed a difference in behaviour between head‐capsule classes. Substrate contacts occurred more frequently in larvae from a lower head‐capsule class and the number of larvae present in a substrate over time differed between the head‐capsule classes 0.71–0.80 mm and 0.91–1.00 mm. Demonstrating arrestment in response to chemical cues from conspecifics is the first step of understanding aggregation behaviour of BSF larvae and offers opportunities to identify the chemical cues involved. [ABSTRACT FROM AUTHOR]

Feeding cost is among the main drivers in the price competitiveness of intensively‐fed‐aquaculture (IFA) products. As soaring energy prices increase the costs of technologies used to increase the digestibility of plant protein feeds, there is an urgent call for comprehensive knowledge on the mass use of insects as fish feed. This review identifies the key aspects of insect incorporation into established IFA practices and puts them into a commercial context. Larvae of Black soldier fly (BSFL) is identified as the most versatile in terms of (a) variety of biowaste usable for its rearing, (b) automatization and scaling up, (c) nutritional value and (d) circular and environmental aspects. Furthermore, modifications insect diets can increase the levels of valuable compounds such as omega‐3 fatty acids in fish. Other insects such as ants or mealworms have the potential to meet the nutritional requirements of various fish species. While today the production costs of BSFL (mostly around 3.5 € kg−1) are mostly determined by labour costs, it is predicted that intensified industrialization of insect rearing could reduce the production cost below 2 € kg−1. In addition, multiple positive economic impacts, as well as environmental spillovers, have been identified. It is proposed that further research should be directed towards the refining and further valorization of byproducts from insect farming which could further dissolve the rearing cost. Bringing the IFA into compliance with the principles of the circular economy increases its competitiveness by reducing production costs and improving public opinion. [ABSTRACT FROM AUTHOR]

The raw material for the production of chitosan, which has a wide application in science and industry, is chitin, one of the most abundant natural polymers. The transformation of chitin into chitosan is carried out by the substitution of the acetamide functional group for the amine one, and is quantified by the deacetylation degree (DD). In order to determine the DD of the chitin and chitosan samples, the coherent anti‐Stokes Raman spectroscopy (CARS) has been applied in this study. The changes in the intensity of the resonant bands, related to the vibrations of acetamide group, were utilised as an indicator of the DD. By measuring the chitin/chitosan samples of different DD, with the values ranging from 8% to 95%, we were able to obtain the calibration curve of the CARS response. In such a way, the CARS microscope has been prepared for the characterisation of the chitin/chitosan species of unknown origin and for their structural imaging. The shell of the larvae of the Hermetia illucens, also known as the black soldier fly, was chosen as the subject of testing. It is one of the promising sources of raw material for chitosan production. The CARS microscopy capabilities were demonstrated by imaging the black soldier fly's shell and depicting the structural distribution of the DD within the larvae's shell. [ABSTRACT FROM AUTHOR]

Development time, survival and final nutrient content of Hermetia illucens L. larvae depends on the substrates in which they develop. Mixing different waste types together can increase the performance and survival of the larvae, as well as their waste reduction. The main objective of this study was to evaluate the effect of different ratios of mixed fruit and vegetable waste with poultry manure on larval development time, size, biomass production, survival, bioconversion and waste reduction. Freshly hatched neonates (90 mg; approx. 6000 individuals) were placed on 12 kg of a mixture of fruit and vegetable waste and fresh, unprocessed poultry manure and held at 28 ± 0.5°C. Inclusion of fruit and vegetable waste varied from 0% to 100% in 10% increments. Initial temperature of the substrate was also measured. The individual mass of larvae increased significantly as more fruit and vegetable waste was included, from less than 81.3 ± 6.6 mg on poultry manure only to an average size of 211.6 ± 6.0 mg at 100% fruit and vegetable waste. After approximately 60% inclusion of fruit and vegetable waste the performance and survival of the larvae increased significantly while development time was reduced. A combination of high fruit and vegetable waste and low initial temperatures resulted in lower development time overall. The mixing of wastes can be applied in industry to further the goals of waste reduction and biomass production while incorporating low‐quality wastes like poultry manure. [ABSTRACT FROM AUTHOR]

The micro‐evolutionary forces that shape genetic diversity during domestication have been assessed in many plant and animal systems. However, the impact of these processes on gene expression, and consequent functional adaptation to artificial environments, remains under‐investigated. In this study, whole‐transcriptome dynamics associated with the early stages of domestication of the black soldier fly (BSF), Hermetia illucens, were assessed. Differential gene expression (DGE) was evaluated in relation to (i) generational time within the cultured environment (F2 vs. F3), and (ii) two selection strategies [no artificial selective pressure (NS); and selection for greater larval mass (SEL)]. RNA‐seq was conducted on 5th instar BSF larvae (n = 36), representing equal proportions of the NS (F2 = 9; F3 = 9) and SEL (F2 = 9; F3 = 9) groups. A multidimensional scaling plot revealed greater gene expression variability within the NS and F2 subgroups, while the SEL group clustered separately with lower levels of variation. Comparisons between generations revealed 898 differentially expressed genes (DEGs; FDR‐corrected p < 0.05), while between selection strategies, 213 DEGs were observed (FDR‐corrected p < 0.05). Enrichment analyses revealed that metabolic, developmental, and defence response processes were over‐expressed in the comparison between F2 and F3 larvae, while metabolic processes were the main differentiating factor between NS and SEL lines. This illustrates the functional adaptations that occur in BSF colonies across generations due to mass rearing; as well as highlighting genic dynamics associated with artificial selection for production traits that might inform future selective breeding strategies. [ABSTRACT FROM AUTHOR]

Reliable options to control the cabbage root fly, Delia radicum L., are lacking in many countries as restrictions on insecticide use have tightened due to environmental concerns. Although microbial control agents are often considered as a sustainable alternative, their application in agriculture is constrained by inconsistent efficacy owing to low field persistence. To stimulate naturally occurring beneficial microbes, soil amendment with the residual streams of insect production has been suggested as an alternative to synthetic fertilization and a new approach to microbial crop protection. In a set of greenhouse experiments, exuviae and frass of black soldier fly larvae, Hermetia illucens L., house crickets, Acheta domesticus L. and exuviae of mealworms, Tenebrio molitor L., were added to soil from an organically managed field. Exuviae and frass treatments were compared to treatments with synthetic fertilizer. Brussels sprouts, Brassica oleracea L., plants were grown in amended soil for 5 weeks before being infested with cabbage root fly larvae. Insect and plant performance were assessed by recording cabbage root fly survival, biomass and eclosion time and seed germination and plant biomass, respectively. Whereas soil amendment with black soldier fly frass or exuviae reduced cabbage root fly survival and biomass, respectively, amendment with house cricket or mealworm residual streams did not negatively affect root fly performance. Furthermore, seed germination was reduced in soil amended with house cricket exuviae, while amendment with either residual stream derived from black soldier fly larvae or house crickets resulted in lower plant shoot biomass compared with the synthetic fertilizer treatment. Amending soil with black soldier fly residual streams could become a novel and low‐cost tool to be integrated in cabbage root fly management programmes, especially where methods currently available are insufficient. Therefore, the mechanisms underlying the effects of insect‐derived soil amendments described here should be the focus of future research. [ABSTRACT FROM AUTHOR]

Keywords: Atlantic salmon; calcification; gallbladder; inflammation; pathology EN Atlantic salmon calcification gallbladder inflammation pathology 281 285 5 02/09/23 20230301 NES 230301 Gallbladders with mucosal outpouchings (diverticula) were found in a population of Atlantic salmon farmed in sea water. In May 2020, 70% of the skin samples, 38% of distal intestine and 8% of the pyloric caeca samples had calcified lesions (Figures 3 and 4), while only one fish had inflammation in red muscle tissue. Atlantic salmon, calcification, gallbladder, inflammation, pathology. [Extracted from the article]