Yellow Mealworm Research Articles

Integrating microbiome and transcriptome analyses to understand the effect of replacing fishmeal with Tenebrio molitor meal in Pacific white shrimp (Litopenaeus vannamei) diets

With the increasing price and demand for fishmeal (FM) in aquaculture feeds, Tenebrio molitor (TM), an insect species known as yellow mealworm, is becoming an attractive alternative to FM in the aquaculture industry. This study investigated the effect on growth, enzyme activity, resistance to Vibrio parahaemolyticus, intestinal microbiota, and hemolymph transcriptome in Litopenaeus vannamei (Pacific white shrimp) of replacing up to 45% of FM with TM. L. vannamei (initial weight: 0.42 ± 0.01 g) were fed with diets that replaced FM with TM at 0% (TM0, control), 15% (TM15), 30% (TM30), and 45% (TM45). The results showed that dietary TM30 significantly increased the final body weight (FBW), weight gain rate (WGR), and specific growth rate (SGR) of L. vannamei (P < 0.05) when compared with TM0. For the enzyme activity of serum, alkaline phosphatase (AKP), catalase (CAT), superoxide dismutase (SOD), phenoloxidase (PO), and lysozyme (LZM) differed significantly in TM45 compared with TM0 (P < 0.05), and malondialdehyde (MDA) decreased. The trypsin in the intestine significantly increased in TM45 compared with TM0 (P < 0.05). In the shrimps challenged with V. parahaemolyticus (1.3 × 107 CFU/mL), survival rates were not significantly different between groups. The alpha diversity indicators were significantly affected by feeding different levels of TM (P < 0.05), and beta diversity analysis showed that the four groups differed significantly (P < 0.05). Based on IndVal values, eight families were distinguished. RNA-seq analysis showed that the most enriched pathway was ‘Metabolism of xenobiotics by cytochrome P450’. Some DEGs (differentially expressed genes) of the cytochrome P450 pathway correlated with the abundance of intestine bacteria at the family level. This study provides an insight into the mechanisms associated with molecular and microbiota responses to the effects of substituting TM for FM on L. vannamei, as well as suggests that TM is a potential protein source for farmed L. vannamei, possibly improving its antioxidant capacity, immunity, and resistance to disease via the cytochrome P450 pathway.

Impact of physiochemical properties of protein ingredients on pellet quality and microstructure

The objective of this study was to evaluate the effect of different protein ingredients on the physical quality of extruded pellets. Five experimental diets were based on five formulations using fish meal (FM), poultry by-product meal (PBM), and three novel protein ingredients, yellow mealworm (YM), Clostridium ethanolic protein (CAP), and Chlorella variabilis (high protein strain, CV), mixed with wheat flour in a 7:3 ratio. The results showed that the CAP had the highest content of water absorption index and the lowest value of crude lipid. The pellets containing CAP had the lowest water solubility while having the highest expansion ratio. The CV had the highest values of crude lipid and pasting properties (peak viscosity and final viscosity). The feed containing CV had the highest hydration time. The PBM had the highest content of crude lipid and produced pellets with the lowest expansion ratio and floatability. The FM and YM had similar physiochemical properties and the qualities of pellets containing both were also similar. The extruded pellets produced with CAP had the highest pore area and porosity, while extruded pellets containing PBM had a smallest pore area and porosity. Furthermore, the pore area and porosity of extruded pellets containing CV were significantly lower than that of the CAP, FM, and YM groups, and had thicker pore wall structures (P < 0.05). Overall, the comprehensive physical quality score of the extruded pellets, feed containing CAP ranked first, followed by feed formulated with FM, YM, and CV, while PBM ranked last.

Yellow Mealworm (Tenebrio molitor) and Lesser Mealworm (Alphitobius diaperinus) Proteins Slowed Weight Gain and Improved Metabolism of Diet-Induced Obesity Mice

BackgroundHigh-protein diets not only meet amino acid needs but also modulate satiety and energy metabolism. Insect-based proteins are sustainable, high-quality proteins. Mealworms have been studied, but limited information is known about their ability to impact metabolism and obesity. ObjectiveWe determined the effects of defatted yellow mealworm (Tenebrio molitor)- and whole lesser mealworm (Alphitobius diaperinus)-based proteins on the body weight (BW), serum metabolites, and liver and adipose tissue (AT) histology and gene expression of diet-induced obesity mice. MethodsMale C57BL/6J mice were fed a high-fat diet (HFD; 46% kcal) to induce obesity and metabolic syndrome. Obese mice were then assigned to treatments (n = 10/group) and fed for 8 wk: HFD: HFD with casein protein; B50: HFD with 50% protein from whole lesser mealworm; B100: HFD with 100% protein from whole lesser mealworm; Y50: HFD with 50% protein from defatted yellow mealworm; Y100: HFD with 100% protein from defatted yellow mealworm. Lean mice (n = 10) fed a low-fat-diet (LFD; 10% kcal) were included. Longitudinal food intake, BW, body composition, and glucose response were measured. At time of killing, serum metabolites, tissue histopathology and gene expression, and hepatic triglycerides were analyzed. ResultsAfter 8 wk, HFD, B50, and B100 had greater (P < 0.05) weight gain than LFD, whereas Y50 and Y100 did not. Y50, B100, and Y100 had a lower (P < 0.05) BW change rate than HFD. Mealworm-based diets led to increased (P < 0.05) serum high-density lipoprotein (HDL) and reduced (P < 0.05) serum low-density lipoprotein (LDL) concentrations and reduced (P<0.05) LDL/HDL ratio. Mealworm-based diets led to increased (P < 0.05) hepatic expression of genes related to energy balance, immune response, and antioxidants and reduced (P < 0.05) AT expression of genes associated with inflammation and apoptosis. Mealworm-based diets altered (P < 0.05) hepatic and AT expression of glucose and lipid metabolism genes. ConclusionsIn addition to serving as an alternative protein source, mealworms may confer health benefits to obese patients.

IKKβ regulates antimicrobial innate immune responses in the yellow mealworm, Tenebrio molitor

Toll and IMD pathways regulate antimicrobial innate immune responses in insect model systems. The transcriptional activation of antimicrobial peptides (AMPs) confers humoral immunity in the host against invaded pathogens. The IKK kinase complex (IKKα, IKKβ, and the regulatory subunit IKKγ/NEMO) centrally regulates the NF-κB response to various stimuli. It triggers an appropriate antimicrobial immune response in the host. In this study, a TmIKKβ (or TmIrd5) homolog was screened from the RNA-seq database of the coleopteran beetle, Tenebrio molitor. A single exon characterizes the TmIKKβ gene, and the open reading frame (ORF) comprises of 2112 bp that putatively encodes a polypeptide of 703 amino acid residues. TmIKKβ contains a serine/threonine kinase domain and is phylogenetically close to Tribolium castaneum IKKβ homolog (TcIKKβ). TmIKKβ transcripts were highly expressed in the early pupal (P1) and adult (A5) stages. Among the tissues, TmIKKβ showed higher expression in the integument of the last instar larvae and the fat body and hemocytes of 5-day-old adults. TmIKKβ mRNA was upregulated post-E. coli challenge to the host. Moreover, RNAi-based TmIKKβ mRNA silencing increased host larvae’ susceptibility against E. coli, S. aureus and C. albicans. TmIKKβ RNAi in the fat body led to a downregulation in mRNA expression of ten out of fourteen AMP genes, including TmTenecin1, -2, and -4; TmDefensin, and -like; TmColeoptericinA, and -B; and TmAttacin1a, -1b, and -2, suggesting the requirement of the gene in antimicrobial innate immune responses. Further, a decrease in the mRNA expression of NF-κB factors such as TmRelish, TmDorsal1, and TmDorsal2 in the fat body of T. molitor larvae was observed post-microorganisms challenge. Thus, TmIKKβ regulates antimicrobial innate immune responses in T. molitor.

The use of yellow mealworms in common food products

In many cultures around the world, eating insects is a traditional practice known as entomophagy. In general, it has been discovered that insects are very nutrient-dense and good sources of protein, fat, minerals, vitamins and energy. Given their high nutritional value and minimal impact on the environment, edible insects are increasingly being recognized as potential sources of food for humans. The green light for using edible insects was given for the following species - Tenebrio molitor, Acheta domesticus, Alphitobius diaperinus and Locusta migratoria. Out of them Tenebrio molitor is the most widely researched and used species. Considering many of the potential uses of Tenebrio molitor in commercial food, this paper will summarize the potential of their use in food such as bread, meat products and sauces. This paper will also provide an overview of the nutritional value of dried Tenebrio molitor.

Safety of UV-treated powder of whole yellow mealworm (Tenebrio molitor larva) as a novel food pursuant to Regulation (EU) 2015/2283.

Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on UV-treated powder of whole yellow mealworm (Tenebrio molitor larva) as a novel food (NF) pursuant to Regulation (EU) 2015/2283. The term yellow mealworm refers to the larval form of the insect species T. molitor. The NF is the UV-treated powder of the whole, thermally dried yellow mealworm. The NF consists mainly of crude protein, fat, digestible carbohydrates and fibre (chitin). The Panel notes that the levels of contaminants in the NF highly depend on the occurrence levels of these substances in the insect feed. The Panel notes furthermore that there are no safety concerns regarding the stability of the NF if the NF complies with the proposed specification limits during its entire shelf life. The NF has a high protein content, although the true protein content in the NF is overestimated when using the nitrogen-to-protein conversion factor of 6.25, due to the presence of non-protein nitrogen. The applicant proposed to use the NF as an ingredient in various food products, such as bakery products, pasta, compotes of fruit/vegetables and cheese. The target population is the general population. The Panel notes that considering the composition of the NF, the proposed conditions of use and that the NF will not be the sole source of dietary protein, the consumption of the NF is not nutritionally disadvantageous. Despite the UV treatment, the Panel notes that the NF is not a significant dietary contributor of vitamin D3. The submitted toxicity studies from the literature did not raise safety concerns. The Panel considers that the consumption of the NF may induce primary sensitisation and allergic reactions to yellow mealworm proteins and may cause allergic reactions in subjects with allergies to crustaceans and dust mites. Additionally, allergens from the feed may end up in the NF. With the exception of possible allergenicity, the Panel concludes that the NF is safe under the proposed uses and use levels.

Growth performance, welfare traits and meat characteristics of broilers fed diets partly replaced with whole Tenebrio molitor larvae

The role of insects in animal nutrition has been reconsidered during recent years, paving the way for an increasing market for edible insects. Their protein and amino acid balance make them a promising source of protein for replacing high value proteins. Yellow mealworm, Tenebrio molitor L. (TM; Coleoptera: Tenebrionidae) larvae, have shown positive effects on broiler performance in several research studies and have a strong potential as a sustainable alternative protein source for monogastric animals. This study aimed to assess the effect of replacing various ratios of basal diets with T.molitor larvae on broiler performance as well as on several meat and welfare characteristics. For the study, 120 one-day-old male chicks (Ross 308) were randomly allocated in 3 treatments and 4 replications (10 birds per pen). Birds of the control group (basal diet) were fed with typical commercial maize and soymeal-based rations in mash form. The other 2 groups were treated with the same diet, after replacing 5% and 10% with dried TM larvae, respectively. On d 35 (end of trial), meat samples were collected and analysed. Body weight, feed intake, body weight gain and feed conversion ratio during the periods of 1 to 10d (starter period), 11 to 24d (grower period), 25 to 35d (finisher period) and 1 to 35d (total period) were assessed. Pododermatitis, diarrhoea, feather score and litter conditions were also assessed during the trial. The results indicated that TM larvae inclusion in the broilers' diet positively affected body weight gain values, as well as the carcass yield, the meat composition and various welfare traits. Additionally, the dietary treatments with TM larvae favourably affected meat composition and colour parameters, whereas there were also some positive effects on lipid and protein oxidation. Saturated fatty acids were decreased by the dietary supplementation whereas the polyunsaturated fatty acids to SFA ratio increased. In general, the study showed that whole TM larvae addition can provide a promising alternative to soybean meal in the diet of broilers, demonstrating a positive impact on growth, welfare and meat characteristics.

Different Diets Based on Yellow Mealworm (Tenebrio molitor)—Part A: Facing the Decrease in Omega−3 Fatty Acids in Fillets of Rainbow Trout (Oncorhynchus mykiss)

Aquaculture struggles with sustainability due to the use of fishmeal, and insects are one potential alternative. Insects have low long-chain omega−3 polyunsaturated fatty acid content, and insect-fed fish reflect this in their composition. In total, 500 rainbow trout (Oncorhynchus mykiss, ~46 g) were fed until the fish reached a commercial size (~415 g). Five diets were used: one control based on fishmeal as main source of protein; two with a 50% replacement of fishmeal with yellow mealworm meal (Tenebrio molitor), one with full-fat insect, and another partially defatted; two other diets similar to the one with the full-fat insect, but with the addition of an experimental algal oil rich in omega−3 in two different concentrations (one equivalent to control, the other one to the defatted insect diet). Growth was unaffected, as well as texture and organoleptic profile of the fillets. Lightness, brightness and colour of the fillets were slightly modified by the experimental diets. An increase in omega−3 levels over those of the full-fat insect diet is described. An omega−3 sparing effect was highlighted, causing lipid accumulation in fillets and liver, and a mild increase in oxidative damage. More research is encouraged to evaluate the fatty acid profile of the liver.

Different Diets Based on Yellow Mealworm (Tenebrio molitor)—Part B: Modification of the Intestinal Inflammatory Response and the Microbiota Composition of Rainbow Trout (Oncorhynchus mykiss)

With the purpose of improving aquaculture sustainability, the search for protein alternatives to fishmeal makes it necessary to test different variables and the possible repercussions of new ingredients. The use of insect meal as a protein source for aquaculture is well described, but the complex composition of insect meals (fat and other components) can affect the physiology of fish. For this reason, as a part of a bigger study, the aim of the current manuscript was to test diets based on three different presentations of insect meal coming from yellow mealworm (Tenebrio molitor): full fat, partially defatted, and supplemented with a long chain omega–3-enriched oil, and to evaluate their effects on protein digestibility, biometric indices, immunological system and gut health (intestinal histomorphology and microbiota) of rainbow trout (Oncorhynchus mykiss). Digestibility of the protein and body indices showed a minor but consistent trend. The non-specific immunological system did not show changes, but the histology of the intestine showed signs that insect meals could be softening a mild inflammatory response. The gut microbiota suffered several changes, which could be associated with the different amino acid and fatty acid compositions of the diets.

Tenebrio molitor (Linnaeus, 1758): Microbiological Screening of Feed for a Safe Food Choice.

As a result of the increasing focus on alternative protein sources which are ideally still sustainable, the yellow mealworm, Tenebrio molitor, has come into focus. To verify its suitability as a food source in relation to human health, an analysis of the microbiome of larvae of T. molitor is pertinent. Subsequently, the focus of this study was, on the one hand, to analyze the influence of the substrate on the microbial load of the larvae microbiome, and, on the other hand, to determine which processing methods ensure the risk-free consumption of mealworms. For this purpose, mealworms were grown on 10 different substrates derived from by-products of food production (malt residual pellets, corn germ meal, chestnut breakage and meal, wheat bran, bread remains, draff, nettle, hemp seed oil cake, oyster mushrooms with coffee grounds, pumpkin seed oil cake) and microbial loads were analyzed using different selective media. Further starvation/defecation and heating (850 W for 10 min) methods were used to investigate how the reduction of microorganisms is enabled by these methods. The results showed that there was no significant relationship between the microbial load of the substrate and the mealworm. Starvation and defecation led to a lower stock of microorganisms. Heating led to a significant microbial reduction in non-defecated mealworms. The group of defecated and heated mealworms showed no detectable microbial load. In conclusion, firstly, the choice of substrate showed no effect on the microbial load of larvae of Tenebrio molitor and secondly, heating and starvation allow risk-free consumption. This study makes an important contribution for evaluating the safety of mealworms as a sustainable protein source in human nutrition.

Dietary Inclusion of Crickets (Acheta domesticus) and Yellow Mealworm Meal (Tenebrio molitor) in Comparison with Soybean Meal: Effect on the Growth, Total Tract Apparent Digestibility, and Nitrogen Balance of Fattening Rabbits.

Three diets were formulated, i.e., soybean meal (SM diet), adult Acheta domesticus (AD diet), and Tenebrio molitor larvae (TM diet), as the main crude protein (CP) sources. A total of 45 rabbits (Hyplus, weaned at 32 days of age) were divided into three groups (15 per treatment) and fed one of the three diets for 42 days. A higher daily weight gain (p = 0.042), as well as daily feed intake (p = 0.022), was observed in rabbits fed the AD and TM diets than in rabbits fed the SM diet within 21 days after weaning. The coefficients of total tract apparent digestibility (CTTAD) of gross energy were higher (p = 0.001) in rabbits fed the SM diet than in rabbits fed the other diets. The CTTAD of CP (p = 0.040) and starch (p = 0.041) was higher in rabbits fed the SM diet compared to those fed the AD diet. There were non-significantly higher losses of nitrogen in the urine (an average by 0.227 g/day; p = 0.094) in rabbits fed the TM diet than in rabbits fed the other diets. It can be concluded that the growth of rabbits and nitrogen output were not detrimentally affected by the insect meal (AD or TM) used in this study.

Effects of defatted yellow mealworm (Tenebrio molitor) on growth performance, intestine, and liver health of turbot (Scophthalmus maximus)

Yellow mealworm Tenebrio molitor is an emerging feed ingredient with several key advantages. However, research on the T. molitor as a fishmeal substitute reported discrepancies in feasibility in different fish species, with a particular need for T. molitor products to be widely evaluated. In this research, an eight-week feeding trial was conducted to evaluate the effect of T. molitor on turbot Scophthalmus maximus mainly from the perspective of growth performance and health status of the intestine and liver. Turbot with an initial weight of approximately 150 g were randomly assigned six isonitrogenous and isolipidic diets, including fishmeal-based control diet or diets with gradually increasing level of defatted T. molitor meal (TM) to replace 15 % (TM15), 30 %, 45 %, 60 % and 75 % of fishmeal compared to the control diet. Weight gain of turbot increased significantly at the 30 % replacement level (P < 0.05). However, TM in 45 %, 60 % and 75 % of fishmeal replacement level impaired overall growth performance. There was no obvious impairment in the assayed levels of TM towards the intestine from the view of structure, activities of brush border enzymes, antioxidant conditions, or immunity of proximal, middle and distal segments. However, the amount of goblet cells was significantly decreased by TM (P < 0.05). Similarly, TM in the assayed levels did not induce any negative effects on the antioxidant and immune status of the liver. But TM45, TM60 and TM75 diets induced weight loss in the liver and smaller hepatocytes, accompanied by a decrease of liver lipid content as well as decreases in levels of triglyceride and cholesterol in plasma. In conclusion, the optimal dietary level of TM for turbot was 24.5 %, corresponding to a 30 % substitution of fishmeal from the control group. Dietary TM can improve the antioxidant and immune function of the intestine and liver, but excess TM will disturb lipid metabolisms.

Life Cycle Assessment of Black Soldier Fly, Yellow Mealworm and Soybean Protein for Use in Fish Feed

As the consumption of fish in the human diet increases, a larger amount of production is needed. The growing demand for fish also has an impact on fish feed, its production efficiency and the sustainability of using raw materials. To evaluate the sustainability of raw materials and the impact on the environment, three protein alternatives are compared – black soldier fly, yellow mealworm and soybean. Each alternative has advantages and disadvantages. The advantages of black soldier fly and yellow mealworm are a valuable source of protein, sustainable growth (as feed can be used for food waste) and no need for arable land. Disadvantages of black soldier fly and yellow mealworm are price, an unbalanced diet can negatively affect growth, and nutritional value effect on the fish vary depending on fly or mealworm species. The advantages of soybeans are price, availability and high protein content, but the disadvantages are a lack of essential amino acids that affect the quality of fish and poor palatability. An LCA study has been carried out for the black soldier fly, yellow mealworm and soybean protein. From PEFCR most relevant impact categories are climate change, particulate matter, acidification, land use, eutrophication terrestrial and water use. The total single score value for black soldier fly protein is 1.43E+01 μPt, for yellow mealworm protein is 3.89E+02 μPt and for soybean protein is 9.72E+01 μPt. Large impact is from electricity consumption, used components for feed. Sensitivity analysis was performed for black soldier fly protein and yellow mealworm protein production, where feed composition was changed. In sensitivity analysis environmental impact is less from the new feed structure. The reason might be that the new feed structure has used food waste and wheat as feed ingredients.

Harmful and beneficial symbionts of Tenebrio molitor and their implications for disease management

The yellow mealworm, Tenebrio molitor, is currently one of the most important insect species produced for livestock feed and human consumption. High-density rearing conditions make the risk of disease and infections by parasitic symbionts a challenge in the mass production of these insects. However, certain symbionts are beneficial and should be favoured in order to promote healthy insect populations. Knowledge of parasitic symbionts and their management is essential for the insect rearing industry and its associated research. Here we review the documented microbial infectious agents, invertebrate parasites, and beneficial symbionts occurring in T. molitor. Furthermore, we discuss detection, prevention, and treatment methods for disease management in T. molitor production systems to inform future management and decision making in T. molitor rearing.

Population Growth of Three Stored Product Beetle Species on Alphitobius diaperinus (Coleoptera: Tenebrionidae) Meals.

The lesser mealworm, Alphitobius diaperinus (Panzer) (Coleoptera: Tenebrionidae), is an important pest of stored products and at the same time a species with great potential as food and feed that has recently attracted increasing interest as nutrient source. Future predictions show a massive increase of insect meals' production in the near future, therefore, as expected in the case of other durable stored products, insect meals may get infested by insects during their storage. In this context and as a continuance of our previous study on the susceptibility of meal of the yellow mealworm, Tenebrio molitor L. (Coleoptera: Tenebrionidae), to storage insect infestations, the objective of this study was to test the susceptibility of A. diaperinus meals to infestations of three stored products pests, namely A. diaperinus itself, T. molitor, and the red flour beetle, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae). The population growth of the three species was evaluated on pure A. diaperinus meal, as well as on A. diaperinus meal-based substrates with different percentages of wheat bran (0, 25, 50, 90, and 100% bran). Our results showed that all three insect species tested were able to grow and develop on the A. diaperinus meal-based substrates evaluated, giving in a short time high population densities. This study confirms again our initial theory for insect infestations during storage of insect-based products.

Effects of Yellow Mealworm (Tenebrio molitor) on Growth Performance, Hepatic Health and Digestibility in Juvenile Largemouth Bass (Micropterus salmoides).

This study investigated the effects of yellow mealworm meal (TM) on growth performance, hepatic health and digestibility in juvenile largemouth bass (Micropterus salmoides). The fish were fed with the basic feed and the test feed (70% basic feed and 30% raw materials) containing Cr2O3, and feces were collected for digestibility determination. The fish were fed with five isonitrogenous (47% crude protein) and isolipidic (13% crude lipid) diets, in which fishmeal (FM) was replaced with 0% (TM0), 12% (TM12), 24% (TM24), 36% (TM36) and 48% (TM48) TM. The fish were reared in cylindrical plastic tanks in a recirculating aquaculture system for 11 weeks. The apparent digestibility coefficients (ADC), of dry matter, crude protein and crude lipid, in largemouth bass of TM were 74.66%, 91.03% and 90.91%, respectively. The ADC of total amino acid (TAA) of TM in largemouth bass was 92.89%, and the ADC of essential amino acid (EAA) in TM in largemouth bass was 93.86%. The final body weight (FBW), weight gain rate (WGR) and specific growth rate (SGR) in the TM24 group were significantly higher than those in other groups. Similarly, the highest mRNA expression levels of hepatic protein metabolism genes (pi3k, mtor, 4ebp2 and got) and antioxidant enzyme (glutathione peroxidase, Gpx; catalase, Cat) activities were observed in the TM24 group. Moreover, the expression levels of anti-inflammatory factors (il-10 and tgf) in liver were up-regulated and the expression levels of pro-inflammatory factors (il-8 and il-1β) in liver were down-regulated. Quadratic regression model analysis, based on weight gain rate (WGR) against dietary TM level, indicated that the optimum level of dietary TM replacing FM in largemouth bass diet was 19.52%. Appropriate replacement levels (less than 36%) of FM by TM in the diets can enhance the antioxidant capacity and immunity of largemouth bass. However, high levels of FM substitution with TM (more than 48%) in the feeds can damage the liver health and inhibit the growth of largemouth bass. Notably, largemouth bass has high ADC and high utilization of TM, which indicates that it is feasible to use TM as feed protein source for largemouth bass.

Does dietary inclusion of defatted yellow mealworm (Tenebrio molitor) affect growth and body composition of juvenile common carp (Cyprinus carpio)?

The objective of this study was to evaluate the effects of total and partial replacement of fishmeal with defatted yellow mealworm (Tenebrio molitor) meal on one-summer-old common carp (Cyprinus carpio) with an initial bodyweight of 97.54 g ± 51.0 g. Fish were kept in an experimental recirculating aquaculture system (9 x 250 L tanks) and fed with two experimental diets formulated with mealworm meal replacements and one control, which had 100 g/kg fishmeal without mealworm meal (MWM0). In the first treatment, 50% of fishmeal was replaced with mealworm meal (MWM50). In the second treatment, fishmeal was replaced totally with mealworm meal (MWM100). Fish were fed three times per day at 3.0% of fish biomass. After six weeks of the experimental period, growth performance, nutrient utilization, body composition, and biometric indices were compared. The results revealed that the growth performance of common carp was not affected significantly by the inclusion level of mealworm meal. However, the highest weight gain was observed in MWM100, where specific growth rate was 0.76 ± 0.10 g/day. Crude fat content of the fish body differed significantly between experimental groups and the control. This investigation demonstrated that MWM could be used as an alternative dietary protein source to replace fishmeal without adverse effects on the growth performance of one-summer-old common carp.

Yellow mealworm (Tenebrio Molitor) enhances intestinal immunity in largemouth bass (Micropterus salmoides) via the NFκB/survivin signaling pathway

This study aimed to elucidate the mechanisms of yellow mealworm (Tenebrio Molitor, YM) in intestinal immunity and health. Largemouth bass, as an enteritis modeling animal, were fed 3 diets containing YM at 0% (YM0), 24% (YM24) and 48% (YM48). The YM24 group had reduced levels of proinflammatory cytokines, while the YM48 group experienced a negative impact on intestinal health. Next, the Edwardsiella tarda (E. tarda) challenge test consisted of 4 YM diets, 0% (EYM0), 12% (EYM12), 24% (EYM24), and 36% (EYM36). The EYM0 and EYM12 groups exhibited intestinal damage and immunosuppression by the pathogenic bacteria. However, the above adverse phenotypes were attenuated in the EYM24 and EYM36 groups. Mechanistically, the EYM24 and EYM36 groups enhanced intestinal immunity in largemouth bass via activating NFκBp65 and further upregulating survivin expression to inhibit apoptosis. The results identify a protective mechanism of YM as a novel food or feed source by improving intestinal health.

Biodegradation of polyethylene film by the Bacillus sp. PELW2042 from the guts of Tenebrio molitor (Mealworm Larvae)

The chemical molecular structure of polyethylene (PE) is very stable and extremely difficult to degrade in the environment, thus posing a threat to the environment. In this study, a high-density polyethylene (HDPE)-degrading Bacillus strain PELW2042, was isolated from the gut contents of Tenebrio molitor larvae (yellow mealworms). Results showed that after 42 days of incubation with PELW2042, a large number of pits and cracks were observed on the surface of HDPE film by scanning electron microscopy (SEM). The Fourier Transform-Infrared Spectroscopy (FT-IR) detected absorption peaks near 1700 cm-1 and 1249 cm-1, indicating the formation of carbonyl groups (–CO) and ether groups (–C–O); the X-ray photoelectron spectroscopy (XPS) spectra further demonstrated the generation of new oxygen-containing functional groups. X-Ray Diffraction (XRD) and differential scanning calorimetry (DSC) analyses revealed a 21.63 ± 0.18 % decrease in the relative crystallinity of the HDPE film, indicating that the structure of the HDPE changes. Finally, it was also shown that the weight loss of HDPE film was as high as 17.36 ± 0.56 %. After 42 days of treatment by strain PELW 2042, the molecular weights of the experimental group samples were significantly decreased by 23.31 ± 1.25 % and 30.07 ± 1.37 % for Mw (121700 Da) and Mn (50700 Da), respectively, compared to those of the untreated samples (Mw=158700 Da and Mn=72500 Da). All these results indicate that Bacillus sp. PELW2042 has a high ability to degrade HDPE. This provides a source of strains to accelerate the biodegradation of waste polyethylene plastics.

Effects of Dietary Supplementation with Yellow Meal Worm Larvae (Tenebrio molitor) on Performance of Broiler Chicken

Climate Smart Agriculture (CSA) can sustainably increase productivity, improve resilience, and reduce emissions of greenhouse gases from agricultural systems. The current study aimed to establish the existing knowledge, attitude, and practice of CSA among smallholder farmers in the Isingiro District. An exploratory survey was conducted to collect data from 126 farmers randomly selected from three Sub counties. Key informant interviews were conducted with three extension workers for more information. Data was analysed using Stata 14 to generate summary tables and the Chi-square test of independence. The results revealed a high level of knowledge about CSA among the farmers, with intercropping and crop rotation as the most popular (99%) whereas rainwater harvesting was least known (71.4%). Farmers’ knowledge about CSA was significantly related to different sources of information and knowledge (P&lt;0.05). Farmers showed a positive attitude towards the use of CSA practices except for inorganic fertilisers with 45%. The dominantly used CSA practices were Intercropping (85.7%), mulching (75.4%) and the use of contour bunds (74.6%). Several limitations that hindered the adoption of CSA practices included limited finances, extension services, availability of CSA inputs, high prices of CSA inputs, price fluctuations and land scarcity, among others. The farmers’ awareness, attitude and practice of CSA were mainly shaped by their local knowledge with limited influence of technical knowledge. Furthermore, the practice of CSA among smallholder farmers is hampered by many limitations. Therefore, there is a need for policymakers to prioritise and enact pro-CSA-relevant policies that address the barriers hampering its adoption