Pre-pupae Meal Research Articles

Black Soldier Fly (Hermetia illucens) Meal as Direct Replacement of Complex Fish Feed for Rainbow Trout (Oncorhynchus mykiss) and African Catfish (Clarias gariepinus).

In the experiments, defatted black soldier fly meal reared on vegetable byproducts was used in the fry rearing of two economically important fish species, African catfish and rainbow trout. Both fish species were reared in a recirculation system and 0-33-66-100% of the complex fry feed was replaced by a defatted prepupae meal of black soldier flies during a 28-day feeding experiment. African catfish was reared at 25 ± 1 °C while rainbow trout was reared at 12 ± 1 °C. The results showed that the growth of African catfish was not significantly reduced when 66% of the feed was replaced by soldier fly meal (mean weight in the control fish group at the end of the experiment was 0.4632 ± 0.2469 g, while the 66% group resulted mean weights of 0.4150 ± 0.1886 g) and the survival did not show any statistically different results (mean survival in control group was 57.48 ± 13.76% while it was 56.6 ± 7.763% in the 66% group). In the case of rainbow trout, replacing the feed entirely with insect meal did not cause a decrease in weight gain (final mean weight in the control group was measured at 1.9640 ± 0.4154 g, while in the group consuming only insect meal, it was 1.9410 ± 0.4248 g) or in survival (in the control group 98.5%, while in the group consuming only insect meal 99.5%). All these preliminary results indicate that black soldier fly meal can be used directly as a nursery feed in fish farming as a partial or total replacement of complete feeds. The results showed that black soldier fly meal could replace 66% of the complex brood feed of African catfish and up to 100% of rainbow trout feed without deterioration of production results. Our experiments have therefore opened the way for further experiments on insect meal in larval rearing.

Insect-based aquafeeds modulate the fatty acid profile of zebrafish: A comparison on the different life stages

Insects are considered as an alternative and sustainable ingredient for feed production. In this study, Hermetia illucens (Hi) prepupae (fed on coffee roasted by-product added with 10 % Schyzochytrium sp., a marine protist rich in polyunsaturated fatty acids) was processed into meal and included at graded levels in five experimental diets to replace dietary fish meal (0, 25, 50, 75, 100 %) offered to zebrafish (Danio rerio) as experimental model. The fatty acids (FAs) profile of fish larvae (20 days), juveniles (2 months, deprived of the viscera) and adults (6 months, male and female, deprived of the viscera) specimens was investigated to evaluate the impact of dietary FM replacement with full-fat Hi prepupae meal. For the first time, the quantification of FAs in Danio rerio, performed by gas chromatography-mass spectrometry, was computed in absolute terms (mg 100 g−1 dw), identifying the real variation in the content of any single FA. In fish, quantified total FAs in larvae, juvenile, adult male and adult female were 134 ± 2, 235 ± 8, 266 ± 3 and 266 ± 8 mg g−1 dw, respectively. With respect to zebrafish fed the control diet, specimens fed diet with increasing level of Hi prepupae meal showed significantly higher content of saturated and omega6 FAs, and significantly lower content of poly-unsaturated and omega3 FAs, reflecting partially the FAs composition of the administered diets. At the same time, the docosahexaenoic/eicosapentaenoic acid ratio increased significantly. Moreover, adult female showed a higher content of PUFA with respect to adult male, which could be justified by the needs of physiological reproductive processes. The principal component analysis demonstrated that the FAs composition in Danio rerio depends on both the life stage and the diet.

Enhancing Rearing of European Seabass (Dicentrarchus labrax) in Aquaponic Systems: Investigating the Effects of Enriched Black Soldier Fly (Hermetia illucens) Prepupae Meal on Fish Welfare and Quality Traits.

Within the modern aquaculture goals, the present study aimed to couple sustainable aquafeed formulation and culturing systems. Two experimental diets characterized by 3 and 20% of fish meal replacement with full-fat spirulina-enriched black soldier fly (Hermetia illucens) prepupae meal (HPM3 and HPM20, respectively) were tested on European seabass (Dicentrarchus labrax) juveniles during a 90-day feeding trial performed in aquaponic systems. The experimental diets ensured 100% survival and proper zootechnical performance. No behavioral alterations were evidenced in fish. Histological and molecular analyses did not reveal structural alterations and signs of inflammation at the intestinal level, highlighting the beneficial role on gut health of bioactive molecules typical of HPM or derived from the enriching procedure of insects' growth substrate with spirulina. Considering the quality traits, the tested experimental diets did not negatively alter the fillet's fatty acid profile and did not compromise the fillet's physical features. In addition, the results highlighted a possible role of spirulina-enriched HPM in preserving the fillet from lipid oxidation. Taken together, these results corroborate the use of sustainable ingredients (spirulina-enriched HPM) in aquaponic systems for euryhaline fish rearing.

Insect Larval Meal as A Possible Alternative to Fish Meal in Rainbow Trout (Oncorhynchus mykiss) Diets: Black Soldier Fly (Hermetia illucens), Mealworm (Tenebrio molitor)

This study was conducted to determine the effect on growth performance and intestinal histomorphology of the rainbow trout (Oncorhynchus mykiss) fed diets including black soldier fly (Hermetia illucens) prepupae meal (HI) and mealworm (Tenebrio molitor) larvae meal (TM) used instead of fish meal. Six diets with HI and TM at three inclusion levels (10%, 20% and 30%) and a control diet based on fish meal were prepared. Test diets were encoded as control, HI10, HI20, HI30, TM10, TM20 and TM30. Fish (average initial weight of 34.17±0.88 g) were randomly placed (30 for each) in 500 L fibreglass tanks. Each of the seven diet treatments was tested in triplicated tanks. Fish were fed by hand at a level of 2.5% of body weight three times a day for 90 days. Results demonstrated that the growth performance and intestinal histomorphology were significantly affected by black soldier fly (HI) prepupae meal substitution (p<0.05). HI prepupae meal used instead of the fish meal had a negative effect on the growth performance, but not on the intestinal villi length. In addition, intestinal villi width decreased in fish on diets containing 10% or 20% HI prepupae meal. The growth performance and intestinal histomorphology were significantly affected by diets including TM. The diets containing 20% and 30% TM meal significantly decreased growth performance variables, but intestinal villi length increased. The results suggest that mealworm meal (10%) can be included in diets of rainbow trout at a level of 10% instead of fish meal without adversely affecting growth performance. Future studies should be expanded using a highly defatted TM and HI larvae meals.

Growth and Welfare Status of Giant Freshwater Prawn (Macrobrachium rosenbergii) Post-Larvae Reared in Aquaponic Systems and Fed Diets including Enriched Black Soldier Fly (Hermetia illucens) Prepupae Meal.

Due to the limited application of insect meal in giant freshwater prawn (Macrobrachium rosenbergii) culture, the present study aimed to (i) produce spirulina-enriched full-fat black soldier fly (Hermetia illucens) prepupae meal (HM) and (ii) test, for the first time, two experimental diets characterized by 3% or 20% of fish meal and fish oil replacement with full-fat HM (HM3 and HM20, respectively) on M. rosenbergii post-larvae during a 60-day feeding trial conducted in aquaponic systems. The experimental diets did not negatively affect survival rates or growth. The use of spirulina-enriched HM resulted in a progressive increase in α-tocopherol and carotenoids in HM3 and HM20 diets that possibly played a crucial role in preserving prawn muscle-quality traits. The massive presence of lipid droplets in R cells in all the experimental groups reflected a proper nutrient provision and evidenced the necessity to store energy for molting. The increased number of B cells in the HM3 and HM20 groups could be related to the different compositions of the lipid fraction among the experimental diets instead of a nutrient absorption impairment caused by chitin. Finally, the expression of the immune response and stress markers confirmed that the experimental diets did not affect the welfare status of M. rosenbergii post-larvae.

Spirulina-enriched Substrate to Rear Black Soldier Fly (Hermetia illucens) Prepupae as Alternative Aquafeed Ingredient for Rainbow Trout (Oncorhynchus mykiss) Diets: Possible Effects on Zootechnical Performances, Gut and Liver Health Status, and Fillet Quality

In the present study, an organic substrate (coffee silverskin) enriched with spirulina (Arthrospira platensis; 15% w/w), as a source of lipids and bioactive molecules, was used to rear the black soldier fly (Hermetia illucens) prepupae. Three grossly isonitrogenous, isoproteic, isolipidic and isoenergetic experimental diets for rainbow trout (Oncorhynchus mykiss) juveniles were then produced: a control diet (HM0) mostly including fish meal and fish oil, and two other test diets named HM3 and HM20, in which 3 or 20% of the marine ingredients were substituted with full fat black soldier fly prepupae meal (HM), respectively. Experimental diets were provided for 6 weeks, and at the end of the trial the physiological responses and marketable traits of the fish were investigated using a multidisciplinary approach. Generally, all test diets were well accepted, and fish growth, gut and liver health status, and marketable characteristics were not impaired by the experimental diets. However, an increased immuno-related gene expression along with a slight reduction of fillet redness and yellowness was evident in fish from the HM20 group.

Fishmeal Replacement by Full-Fat and Defatted Hermetia illucens Prepupae Meal in the Diet of Gilthead Seabream (Sparus aurata)

Insect proteins are considered as suitable low environmental impact alternatives to fishmeal for sustainable aquafeeds. Among the different insect species, Hermetia illucens has attracted research and industrial interest due to its ability to grow well on organic side streams, its high protein content and favorable amino acid profiles. Its lipid content although high is characterized by a lack of EPA and DHA that are essential to fish nutrition and thus a defatted form of Hermetia meal might be of better use in fish diets. Hence, two feeding trials were conducted to investigate the effects of the partial fishmeal replacement by increasing levels of a full-fat (up to 276 g/kg) and a defatted (up to 174 g/kg) H. illucens meal on feed intake, growth, feed utilization and nutrient compositions of gilthead seabream (Sparus aurata). Results showed that both the fat content and the inclusion level of H. illucens meal are critical for the success of fishmeal replacement in the diets of S. aurata as they strongly affect feed consumption. A lower palatability of H. illucens meal was observed when included at high dietary levels with the defatted form being more readily accepted by fish. The defatted H. illucens meal is more suitable than the full-fat type to replace fishmeal, with a dietary level of about 81–104 g/kg supporting the highest feed consumption, the highest growth, an unaffected proximate composition and a better feed utilization by S. aurata.

Effects of chicken waste meal and vegetable substrate fed black soldier fly prepupae meal on rainbow trout (Oncorhynchus mykiss)

A feeding trial was conducted to evaluate the effects of the dietary inclusion of black soldier fly (BSF),Hermetia illucens, prepupae in rainbow trout (Oncorhynchus mykiss) fingerling diets on growth performance, fillet quality, and gut and liver histology. Chicken waste meal and fruit & vegetable waste (1:9, v:v) were used as feeding substrates of BSF prepupae. Five diets were prepared: a basal diet (B0) based on fish meal (FM) and four additional diets in which BSF meal (BSFM) was used to replace 25, 50, 75, and 100% of the FM (B25, B50, B75, and B100, respectively). Orthogonal polynomial contrast was used to determine the trend between BSFM inclusion levels and growth parameters, fatty acids, and amino acids. Quadric relationships between the BSFM levels and growth parameters, including length and weight gain rate, specific growth rate (SGRW), and feed conversion rate, were determined. The optimum BSFM inclusion rate for the best SGRW was estimated at 11.9%. With the exception of the B100 group, increasing the BSFM level in the diet generally increases the fatty acid composition of whole fish. Dietary BSFM inclusion resulted in a significant increase in goblet cells in the proximal and distal intestines, as well as muscle layer thickness in the proximal intestine. A histological study showed that substituting fishmeal with BSFM had no effect on liver lipid accumulation. This study showed that replacing FM with BSFM in rainbow trout fingerling diets by 50% had no adverse effects on the growth performance, liver characteristics, feed utilisation, or fillet quality. Therefore, the BSFM described here can safely be used on rainbow trout fingerling diets. As a result, rainbow trout fingerlings can be fed 50% FM/BSFM replacement without adding additional essential amino acids to the diet or eliminating chitin from BSFM using the methods we used to culture BSF.

Effects of black soldier fly (Hermetia illucens) pre-pupae meal on the growth, stress, and immune responses of juvenile rainbow trout (Oncorhynchus mykiss) reared at different stocking densities

The present study investigated the effects of black soldier fly (Hermetia illucens) pre-pupae meal (BM) as a feed ingredient on the growth performance and health status (stress and immune response) of rainbow trout (Oncorhynchus mykiss) reared at different stocking densities. BM was used to replace 5 % of soybean meal in the control diet (CON). Juvenile rainbow trout (4.9 ± 0.2 g) were acclimated and placed in experimental tanks, at stocking densities of 4.9 (low density, LD) and 9.8 (high density, HD) kg/m3. Trout were assigned to four treatments (CON/LD, CON/HD, BM/LD, and BM/HD) in triplicates and reared for 6 weeks. After the feeding trial, fish reared in low-density tanks showed significantly higher weight gain regardless of diet (P < 0.05). In HD groups (CON/HD and BM/HD), however, fish fed the BM diet showed a significantly higher weight gain than those fed the CON diet. The lauric acid (12:0) content of BM groups (BM/LD and BM/HD), in the whole-body, was closely correlated with diets and significantly higher than that of the CON groups (P < 0.05). Fish from the BM/LD group showed significantly higher expression of interleukin 1β (IL-1β), interleukin 8 (IL-8), and immunoglobulin M (IgM) genes compared to the CON groups (P < 0.05). Although no statistical difference was detected, the overall response patterns of liver tissue in antioxidant and immune parameters, including superoxide dismutase (SOD), lysozyme activity (Lyz), IL-1β, and IgM, followed the expression of immune-related genes in response to the different diets and stocking density. In a challenge test with Aeromonas salmonicida for 10 days, fish fed the BM diet showed a significantly higher cumulative survival rate than those fed the CON diet (P < 0.05). These results suggest that BM could be a beneficial feed ingredient for juvenile rainbow trout, but that high stocking densities can negatively influence the growth and immune responses.

Use of black soldier fly (Hermetia illucens) prepupae reared on organic waste as feed or as an ingredient in a pellet-feed formulation for Nile tilapia (Oreochromis niloticus).

The growth and sustainability of freshwater aquaculture are highly dependent on economic feed which is the major running cost. Fish feed industries depend on the high-priced fish meal (FM) as protein source in feed formulations. In this context, a nutrient-rich, and palatable insect meal-based fish feed was developed incorporating the black soldier fly (BSF) (Hermetia illucens) prepupae meal (BSFPM) reared on organic waste imparting additional benefit of waste bioremediation to make cost-effective feed. Feeding trial was conducted to evaluate growth performance on monosex Nile tilapia (Oreochromis niloticus). The different treatments were (1) dried BSF prepupae, (2) BSF prepupae and BSFPM-based feed in 1:1 proportion, (3) BSFPM feed, and (4) control feed with FM. The survival, growth, feed efficiency, and haematological parameters were not significantly different between BSFPM and control feed. Fish fed with control feed and BSFPM feed showed significantly higher (P ≤ 0.05) weight gain, specific growth rate, and percentage weight gain. Lowest food conversion ratio (P ≤ 0.05) was recorded for fish fed control feed with a significantly higher feed efficiency ratio (0.65d ± 0.034) and protein efficiency ratio (2.11a ± 0.063). The mean corpuscular volume of blood in fish fed BSF prepupae (128.5a ± 3.2) is significantly higher. The good growth of fish fed BSFPM feed may be attributed to the essential amino acids which are not limiting in feed. Absence of microbes and safe level heavy metals in BSFPM feed ensures safety of the ingredient. Hence, it can be used as a suitable protein source in feed formulations.

Effects of black soldier fly (Hermetia illucens) enriched with Schizochytrium sp. on zebrafish (Danio rerio) reproductive performances

Nutrient quality, with emphasis on lipid and fatty acid composition of broodstock diet, is one of the major dietary factors influencing fish oocytes maturation, reproductive success and offspring quality/survival. The Black Soldier Fly (BFS) (Hermetia illucens) is a valuable insect species characterized by a balanced essential amino acid profile comparable to fishmeal and has been demonstrated to be an eco-friendly and low-cost protein source in fish diets. However, as regards lipids, BFS is usually characterized by a poor content in polyunsaturated fatty acids which are essential for fish during critical life-cycle stages including oocyte maturation and reproduction.In the present study, full-fat enriched BSF prepupae meal was obtained from BSF larvae reared on coffee by-product (coffee silverskin) enriched with 10% of Schizochytrium sp. Successively, five experimental diets containing different full-fat enriched BSF prepupae meal inclusion levels (corresponding to the 0, 25, 50, 75 and 100% fish meal replacement) were tested during a six-month feeding trial performed on zebrafish (Danio rerio) to investigate, for the first time, the physiological effects on female fish growth, stress response, lipid metabolism and reproductive performances. A multidisciplinary approach including biometric, gas-chromatographic, histological and molecular analyses was used during the present study to have a comprehensive overview of fish responses to the test diets. Results highlighted that up to 50% of fish meal replacement with enriched BSF meal did not impair zebrafish physiological responses while higher replacement levels (75 and 100%) negatively affected fish stress response, oocytes maturation stages, spawning and hatching success.

Performance of defatted black soldier fly pre-pupae meal as fishmeal replacement in the diet of lemon fin barb hybrid fingerlings

This study was conducted to determine the optimal level of defatted black soldier fly pre-pupae (BSFP), Hermetia illucens as a fishmeal replacement in lemon fin barb hybrid diet. Triplicate groups of fish (1.52 ± 0.01 g) were fed twice a day until apparent satiation with five iso-nitrogenous (30 %) and isocaloric (17 kJ g−1) diets containing varying BSFP levels ranging from 0 to 100 % for 8 weeks. No mortality was found during this study. BSFP level used in the diets were significantly affected the growth response of the barb hybrid. The growth performance of fish such as body weight gain and specific growth rate improved up to 75 % BSFP and decreased above this level, while feed conversion ratio and daily feed intake were not affected by BSFP levels. Body protein and lipid contents of the barb hybrid were significantly affected by dietary replacement levels. The protein retention decreased and lipid retention increased when the BSFP level increased, while the carbohydrate retention was extremely low. The most abundant of essential amino acids in the whole body of lemon fin barb hybrid was valine while glutamic acid was the abundant non-essential amino acids. No pathological changes were observed among all dietary fed groups. The present study suggested that fishmeal could be replaced up to 75 % or 2.5 % fishmeal was still required in the lemon fin barb hybrid diet.

Possible Dietary Effects of Insect-Based Diets across Zebrafish (Danio rerio) Generations: A Multidisciplinary Study on the Larval Phase.

Simple SummaryFish meal and fish oil represent the optimal ingredients for aquafeed formulation. However, their partial or complete substitution with more sustainable alternatives, like insects, is required for a further development of the aquaculture sector. Nutritional programming through parental feeding may enhance the ability of the progeny to utilize insect-based diets. In the present study, five experimental diets characterized by increasing fish meal substitution levels with full-fat Black Soldier Fly (Hermetia illucens; BSF) prepupae meal (0%, 25%, 50%, 75% and 100%), used for zebrafish broodstock rearing, were provided to the progeny (first filial generation, F1). The effects of BSF-based diets on F1 zebrafish larvae were investigated through a multidisciplinary approach. No significant differences among the experimental groups were observed in terms of growth, hepatic lipid accumulation and gut health. Furthermore, increasing fish meal substitution levels with BSF prepupae meal resulted in a positive modulation of both stress and immune response. Results demonstrated that nutritional programming via broodstock nutrition should be considered a valuable solution to increase the use of insect meal in aquafeeds formulation and improve fish culture sustainability.Insects represent a valuable and sustainable alternative ingredient for aquafeed formulation. However, insect-based diets have often highlighted controversial results in different fish species, especially when high inclusion levels were used. Several studies have demonstrated that nutritional programming through parental feeding may allow the production of fish better adapted to use sub-optimal aquafeed ingredients. To date, this approach has never been explored on insect-based diets. In the present study, five experimental diets characterized by increasing fish meal substitution levels with full-fat Black Soldier Fly (Hermetia illucens; BSF) prepupae meal (0%, 25%, 50%, 75% and 100%) were used to investigate the effects of programming via broodstock nutrition on F1 zebrafish larvae development. The responses of offspring were assayed through biometric, gas chromatographic, histological, and molecular analyses. The results evidenced that the same BSF-based diets provided to adults were able to affect F1 zebrafish larvae fatty acid composition without impairing growth performances, hepatic lipid accumulation and gut health. Groups challenged with higher BSF inclusion with respect to fish meal (50%, 75% and 100%) showed a significant downregulation of stress response markers and a positive modulation of inflammatory cytokines gene expression. The present study evidences that nutritional programming through parental feeding may make it possible to extend the fish meal substitution level with BSF prepupae meal in the diet up to almost 100% without incurring the well-known negative side effects of BSF-based diets.

Black Soldier Fly (Hermetia illucens) Larvae and Prepupae Defatted Meals in Diets for Zebrafish (Danio rerio).

Simple SummaryAquaculture accounts for 52% of the world’s production of fish for human consumption and its growth relies on finding new alternative protein sources to fishmeal to use in aquafeeds. To make fish feed more sustainable, insects have emerged as valuable alternatives due to their high nutritional value. In this context, black soldier fly (BSF) meals have been used to replace, partially or totally, fishmeal in aquafeeds. However, due to relevant nutritional peculiarities of BSF developmental stages, it is crucial to understand how they can affect fish growth performance and health status. In this study, we evaluated the effects of total dietary replacement of fishmeal with defatted BSF larvae and prepupae meals on the growth performance of zebrafish from larva, through adult stages, in a 60-day feeding trial. Moreover, the effects of the two BSF meals on the expression of genes involved in growth, stress- and immune- responses, as well as hydrolysis of chitin were investigated. Overall, our results showed the beneficial role of defatted BSF meals in zebrafish diet, especially regarding prepupae meal, suggesting that black soldier fly meals could totally replace fishmeal without negatively affecting growth and wellness of zebrafish. The black soldier fly (BSF) Hermetia illucens is receiving increasing attention as a sustainable fishmeal alternative protein source for aquaculture. To date, no studies have explored the effects of fishmeal replacement with BSF V instar larvae or prepupae meals due to their peculiar nutritional properties on fish performances. This study investigated the effects of 100% replacement of fishmeal (control diet) with defatted BSF meals (V instar larvae and prepupae meals, treatments) on growth performance and welfare of zebrafish (Danio rerio), from larvae to adults, in a 60-day feeding trial. Following the inclusion of BSF meals, the expression of key genes involved in growth (igf1, igf2, mstnb, myod1, myog, myf5), hydrolysis of chitin (chia.2, chia.3, chia.5), immune- (il1b, il6, tnfα), and stress- (hsp70 and nr3c1) responses, as assessed by qPCR, was modulated in all of the molecular pathways, except for the stress response. Overall, our findings showed that both BSF meals can totally replace fishmeal without adverse impacts on adult zebrafish growth parameters (final total and standard length, final body weight, weight gain, daily growth rate, specific growth rate) and welfare, with BSF prepupae meal inducing the most beneficial effects, thus suggesting their potential application to meet fish requirements in aquaculture.

Effect of black soldier fly, Hermetia illucens (Linnaeus) prepupae meal on growth performance and gut development in broiler chicken

An experiment was conducted to explore the suitability of black soldier fly (BSF) Hermetia illucens (Linnaeus) prepupae as poultry feed. Ninety day old, unsexed, Cobb chicks were distributed into 2 treatment groups, with 5 replicates, having 9 birds in each replicate, in a completely randomized design. The two dietary treatments consisted of corn-soy control diet and 5% supplemented insect meal-based diet. Results indicated similar (P > 0.05) body weight gain, feed intake or feed conversion ratio in chicks fed either insect meal or control diet during the experimental period. There was also no significant difference (P > 0.05) in the crude protein digestibility, cellular immunity as well as the length or weight of duodenum, jejunum, ileum and caecum between the treatments. It could be concluded that the black soldier fly prepupae meal can be incorporated at 5% in broiler diet. Thus, BSF can play a significant role in converting waste into feed and add to the feed basket in future.

Insects as sustainable feed and food

Submitted 2020-07-06 | Accepted 2020-07-31 | Available 2020-12-01 https://doi.org/10.15414/afz.2020.23.mi-fpap.214-216 Insects are one of the proposed responses to the increasing request of alternative feed/food productions with high production yield and low environmental impact. Insect production offers a new sustainable alternative for unexploited or underexploited resources, in accordance with the waste hierarchy principles. Insects constitute a reliable alternative or addition to feed due to their nutritional characteristics (e.g. protein content, amino acid profile and/or digestibility levels). Edible insects may be part of human foods mostly as ingredients in already well-known products or integration of insect-based foods into existing diets. In the near future research is needed to increase knowledges and support the insect industry to a considerably scale up to reach competitive price and high-quality products. Keywords: entomophagy, novel food, environment, protein, fat Reference Finke, M. D., Rojo, S., Roos, N., van Huis, A., &amp; Yen, A. L. (2015). The European Food Safety Authority scientific opinion on a risk profile related to production and consumption of insects as food and feed. Journal of Insects as Food and Feed, 1(4), 245–247. https://doi.org/10.3920/JIFF2015.x006 Gasco, L., Biancarosa, I., &amp; Liland, N. S. (2020). From waste to feed: A review of recent knowledge on insects as producers of protein and fat for animal feeds. Current Opinion in Green and Sustainable Chemistry. https://doi.org/10.1016/j.cogsc.2020.03.003 Kroeckel, S., Harjes, A.-G. E., Roth, I., Katz, H., Wuertz, S., Susenbeth, A., &amp; Schulz, C. (2012). When a turbot catches a fly: Evaluation of a pre-pupae meal of the Black Soldier Fly (Hermetia illucens) as fish meal substitute — Growth performance and chitin degradation in juvenile turbot (Psetta maxima). Aquaculture, 364–365, 345–352. https://doi.org/10.1016/j.aquaculture.2012.08.041 Lock, E. J., Biancarosa, I., &amp; Gasco, L. (2018). Insects as raw materials in compound feed for aquaculture. In Halloran, A. et al. (eds.) Edible Insects in Sustainable Food Systems. Springer International Publishing (pp. 263–276). Mancini, S., Moruzzo, R., Riccioli, F., &amp; Paci, G. (2019). European consumers’ readiness to adopt insects as food. A review. Food Research International, 122, 661–678. https://doi.org/10.1016/j.foodres.2019.01.041 Murefu, T. R., Macheka, L., Musundire, R., &amp; Manditsera, F. A. (2019). Safety of wild harvested and reared edible insects: A review. Food Control, 101, 209–224. https://doi.org/10.1016/j.foodcont.2019.03.003 Nischalke, S., Wagler, I., Tanga, C., Allan, D., Phankaew, C., Ratompoarison, C., Razafindrakotomamonjy, A., &amp; Kusia, E. (2020). How to turn collectors of edible insects into mini-livestock farmers: Multidimensional sustainability challenges to a thriving industry. Global Food Security, 26, 100376. https://doi.org/10.1016/j.gfs.2020.100376 Sogari, G., Amato, M., Biasato, I., Chiesa, S., &amp; Gasco, L. (2019). The potential role of insects as feed: A multi-perspective review. Animals, 9(4), 119. https://doi.org/10.3390/ani9040119 van Huis, A. (2013). Potential of insects as food and feed in assuring food security. Annual Review of Entomology, 58, 563-583. https://doi.org/10.1146/annurev-ento-120811-153704 van Huis, A. (2020). Insects as food and feed, a new emerging agricultural sector: a review. Journal of Insects as Food and Feed, 6(1), 27–44. https://doi.org/10.3920/JIFF2019.0017 van Huis, A., &amp; Oonincx, D. G. A. B. (2017). The environmental sustainability of insects as food and feed. A review. Agronomy for Sustainable Development, 37(5), 43. https://doi.org/10.1007/s13593-017-0452-8 van Huis, A., &amp; Tomberlin, J. K. (2017). Insects as food and feed : from production to consumption. Wageningen: Wageningen Academic Publishers. van Huis, A., Van Itterbeeck, J., Klunder, H., Mertens, E., Halloran, A., Muir, G., &amp; Vantomme, P. (2013). Edible insects. Future prospects for food and feed security. In FAO Forestry Paper (Vol. 171). Retrieved from http://www.fao.org/docrep/018/i3253e/i3253e.pdf

Can Insect-Based Diets Affect Zebrafish (Danio rerio) Reproduction? A Multidisciplinary Study.

Black Soldier Fly (BSF) meal is considered an alternative, emerging, and sustainable ingredient for aquafeed formulation. However, results on fish physiological responses are still fragmentary and often controversial, and no data are available on the effect of insect meal-based diets on fish reproduction. On this regard, zebrafish, with its relatively short life cycle, represents an ideal experimental model to explore this topic. In this study, female zebrafish were fed for 12 months on a control diet based on fish meal (FM) and fish oil and two experimental diets with full-fat BSF (Hermetia illucens) prepupae meal inclusion, to replace 25% and 50% of FM (BSF25 and BSF50). All diets were isonitrogenous, isolipidic, and isoenergetic. The effects of these two experimental diets on female's reproduction were investigated through a multidisciplinary approach, including the evaluation of growth, gonadosomatic index, spawned/fertilized eggs and hatching rate, adult female carcass and fertilized egg fatty acid composition, histological analysis of the ovary, spectroscopic macromolecular composition of class IV oocytes, and expression of genes involved in fish lipid metabolism in the liver. Results showed that while fish were perfectly able to cope with a 25% insect meal dietary inclusion, a 50% inclusion level caused the overexpression of genes involved in lipid metabolism, a general reduction in the number of spawned eggs, and differences in the frequency rate of previtellogenic oocytes, class III, IV, oocytes and postovulatory follicles and atretic oocytes, in the macromolecular composition of class IV oocytes, and in the fatty acid composition of the fertilized eggs, respect to control and 25% group.

Zebrafish (Danio rerio) physiological and behavioural responses to insect-based diets: a multidisciplinary approach

Black Soldier Fly (BSF) meal is considered as an alternative, emerging and sustainable ingredient for aquafeed production. However, results on fish physiological responses are still fragmentary and often controversial, while no studies are available on fish behavior in response to these new diets. The present work represents the first comprehensive multidisciplinary study aimed to investigate zebrafish physiological and behavioural responses to BSF-based diets. Five experimental diets characterized by increasing inclusion levels (0, 25, 50, 75 and 100% respect to fish meal) of full fat BSF prepupae meal were tested during a 2-months feeding trial. Prepupae were cultured on coffee silverskin growth substrate enriched with a 10% Schizochytrium sp. to improve insects’ fatty acids profile. The responses of zebrafish were assayed through biometric, histological, gas chromatographic, microbiological, spectroscopic, molecular and behavioural analyses. Results evidenced that BSF-based diets affected fish fatty acid composition, while behavioural tests did not show differences among groups. Specifically, a 50% BSF inclusion level diet represented the best compromise between ingredient sustainability and proper fish growth and welfare. Fish fed with higher BSF inclusions (75 and 100%) showed hepatic steatosis, microbiota modification, higher lipid content, fatty acid modification and higher expression of immune response markers.

Amino acid digestibility in housefly and black soldier fly prepupae by growing pigs

An experiment was conducted with the objectives of determining the coefficient of ileal apparent digestibility (CIAD) and the coefficient of ileal standardized digestibility (CISD) of amino acids (AA) in housefly (HF) and black soldier fly (BSF) prepupae meal by growing pigs. Ten pigs fitted with a T-cannula in the distal ileum with an average initial body weight of 25.05 kg were housed individually in metabolism cages equipped with a feeder and a nipple drinker. The pigs were randomly assigned each to one of two diets formulated to contain 976.7 g/kg of HF or BSF as the sole source of nitrogen. A nitrogen-free (N-free) diet was also formulated to estimate the basal ileal endogenous loss (BEL) of AA. All experimental diets contained 2 g/kg titanium dioxide as an indigestible marker. The daily feed allowance was offered in three equal meals that were fed at 0830, 1400 and 1930 h. Each experimental period lasted for 7 days, the initial 4 d for diet acclimation, followed by 3 d for ileal digesta collection and the digesta samples were collected continuously for 12 h. The CIAD of all AA for HF and BSF are more than 0.726 and 0.641, respectively. The values for the CISD of all AA range from 0.870 to 1.608 and from 0.767 to 1.177 for HF and BSF, respectively. Moreover, the values for the CIAD of all AA in HF are greater (P < 0.05) than in BSF. The dispensable AA account for the most proportion of the endogenous fraction and the BEL of proline is the greatest. The values for the CISD of all AA except methionine and cysteine in HF are also greater (P < 0.05) than in BSF. It is concluded that the digestibility of all AA in HF is greater than in BSF in pig.

Assessment of Dietary Supplementation Levels of Black Soldier Fly, Hemertia illucens1, Pre-Pupae Meal for Juvenile Nile Tilapia, Oreochromis niloticus

A critical goal today and for the future is reducing production costs to meet increasing food requirements of the growing world population. Economical, environmentally-conscious, and sustainable aquaculture is essential to meeting the burgeoning food needs. Tilapia are an important component of the global aquaculture industry; a major challenge for the industry is reducing the use of fish oil and fish meal in tilapia production, including with different alternative items such as insects. Sex-reversed juvenile Nile tilapia (Oreochromis niloticus L.) (n = 2,400; 2.1 ± 0.17 g) were fed varying dietary supplementation levels (3, 6, and 9%) of black soldier fly, Hemertia illucens L., pre-pupae meal and evaluated during 49 days in a laboratory. Growth [final body weight, weight gain, specific growth rate, mean biomass, total biomass, and survival], feed utilization [feed conversion ratio and protein efficiency ratio], and feeding cost for the experimental diets were compared with those of a commercial diet. With the exception of protein efficiency ratio, diets for the other parameters analyzed did not differ. Fish fed the check and the 6% black soldier fly meal had significantly larger protein efficiency ratio values (2.66 and 2.65, respectively). Results suggested that tilapia diet could be boosted with 6% black soldier fly meal without negative effect in growth.