Insects are considered as a sustainable protein source for future pet foods. Here we aimed to evaluate the protein quality of larvae of the black soldier fly (Hermetia illucens, BSF), housefly (Musca domestica, HF) and yellow mealworm (Tenebrio molitor, YMW) and to evaluate the fermentation characteristics of their indigestible fractions. Clean freeze-dried larvae were subjected to in vitro simulated canine gastric and small intestinal digestion. Undigested insect residues, shrimp chitin and fructooligosaccharides (positive control, FOS) were incubated for 48 h with inoculum with fresh feces from three dogs simulating large intestinal fermentation. The AA profiles differed among the larvae with proteins from BSF and YMW larvae containing more Val and less Met and Lys than HF larvae. The in vitro N digestibility of the HF (93.3%) and YMW (92.5%) was higher than BSF larvae (87.7%). The BSF larvae also had lower in vitro digestibility values for essential AA (92.4%) and non-essential AA (90.5%) compared to the larvae of the HF (96.6 and 96.5%) and YMW (96.9 and 95.3%). Gas production for FOS increased rapidly during the first 6 h. Low and similar amounts of gas were found for HF larvae and chitin whereas gas production slowly increased over 30 h and was slightly higher at 48 h for BSF than for chitin. Gas production for YMW increased considerably between 6 and 20 h. At 48 h, gas produced for undigested residues was comparable to shrimp chitin and lower than FOS (P < 0.001). Incubation with insect residues resulted in more N-acetylglucosamine than with shrimp chitin (P < 0.05), suggesting higher microbial degradation of insect chitin. Fecal microbiota from one dog appeared to be better able to ferment the undigested residue of YMW as gas production increased considerably between 6 and 20 h of incubation and was higher than for the microbiota from the other two dogs. The associated metabolite profile indicated that acetate, propionate and butyrate were the main fermentation products. Furthermore, formate was produced in relatively high amounts. It is concluded that the protein quality, based on the amino acid profile and digestibility, of selected insect larvae was high with the undigested insect fractions being at least partly fermented by the dog fecal microbiota. As the microbiota from one dog was better capable of fermenting the undigested residue of YMW larvae, it is of interest to further study the selective growth of intestinal microbiota in dogs fed insect-based food.
It has been noted that the introduction of small doses of dry prepupae of Hermetia illucens flies into the diet of the young Mozambique tilapia Oreochromis mossambicus (0.5 g/kg feed) had a positive effect on the growth and development of fish. It was found that the average daily gain in the experimental group was 0.7 g. It was established that the blood biochemical parameters were within the norm in the fish of all groups; however, in the experimental tilapia, the erythrocyte sedimentation rate was significantly lower and a tendency to increase in the amount of hemoglobin and glucose was noted. It was revealed that in the seminiferous tubules of fish in the experimental group, the number of mature sperm was 5.9 times higher compared with the control, indicating an increase in the rate of spermatogenesis. It is assumed that the observed effects are due to the high content of manganese in the prepupae present in a biologically active divalent form.
The use of DLBSF in feed increased ADG of experimental animals during the growing period by 8.3% (612.58±13.53 vs. 565.81±13.60 g, p<0.05) compared to the control group. The survival in the experimental group was 100%, in contrast to the control, where there was retirement of 1 head. It should also be noted that in general in the control group, in some cases, the use of an antibiotic was required for the period of the experiment. In the experimental group, no antibiotic injections were used. Biochemical blood test showed a higher concentration of total protein (61.14±1.40 & 57.57±1.17 vs. 56.99±0.53, g/L, p<0.05), decrease of bilirubin (8.65±0.80 & 9.57±1.33 vs. 13.98±1.12, µmol/L, p<0.05), higher number of leukocytes (12.72±0.53 &14.91±0.52 vs. 8.80±0.89, x 10^9/L, p<0.05) in the blood of the experimental animals compared to the control group. Feeding animals with DLBSF did not affect the number of lactobacilli in the large intestine, while the number of bifid bacteria significantly increased in the control group (3.0х10^14 & 1.4х10^12 vs. 1.0х10^11, CFU/g, p<0.05).
Edible insects are often considered a nutritious, protein-rich, environmentally sustainable alternative to traditional livestock with growing popularity among North American consumers. While the nutrient composition of several insects is characterized, all potential health impacts have not been evaluated. In addition to high protein levels, crickets contain chitin and other fbers that may infuence gut health. In this study, we evaluated the efects of consuming 25 grams/day whole cricket powder on gut microbiota composition, while assessing safety and tolerability. Twenty healthy adults participated in this sixweek, double-blind, crossover dietary intervention. Participants were randomized into two study arms and consumed either cricket-containing or control breakfast foods for 14 days, followed by a washout period and assignment to the opposite treatment. Blood and stool samples were collected at baseline and after each treatment period to assess liver function and microbiota changes. Results demonstrate cricket consumption is tolerable and non-toxic at the studied dose. Cricket powder supported growth of the probiotic bacterium, Bifidobacterium animalis, which increased 5.7-fold. Cricket consumption was also associated with reduced plasma TNF-α. These data suggest that eating crickets may improve gut health and reduce systemic infammation; however, more research is needed to understand these efects and underlying mechanisms.
- Silvia Nogales-Merida, Paola Gobbi, Damian Jozefiak, Jan Mazurkiewicz, Krzysztof Dudek, Mateusz Rawski, Bartosz Kieronczyk and Agata Jozefiak article Insect meals in fish nutrition
Different studies have shown that insect meals can partially or completely replace the fish and soya bean meals that are commonly used in aquaculture. However, information is lacking on the amino acid and fatty acid contents and digestibility of different insect meals. Moreover, we evaluated different proportions of insect diets and determined how these affected the nutritional values of insect meals. Our purpose was to clarify these aspects and consider the availability of protein, amino acids, lipids and fatty acids in insect meals in fish nutrition. Generally,
insect meals have higher indispensable amino acid contents than other meal types, with contents closely related to those in fish meal. Insect meal can be an important source of essential amino acids such as methionine, with contents ranging between 0.47 and 4.03 g 100 g^(-1) sample. These values are higher than those reported for other animal and plant meals. In addition, insects are also good sources of lipids and fatty acids, and the amounts and types of fatty acids vary according to the species, stage of development and type of feed. Moreover, the additional nutritional value of insect meal includes compounds such as chitin, which is primarily considered a fibre but also contains nitrogen and amino acids. Insect peptides with activity against pathogenic microflora provide secondary biological effects, which may significantly improve animal health.
Two age-dependent nitrogen (N) balance studies (average body mass 25 and 60 kg) utilized 16 male castrated piglets and 16 barrows to measure N utilization parameters of diets with complete substitution of SBM by alternative protein sources (SM, HM), but different AA fortifications. Lysine supplementation up to 80% of the recommended lysine (Lys) supply in diets HM (A) and SM (A) yielded similar protein quality data (63.6 ± 2.1 and 63.7 ± 3.4). Surprisingly, only in piglet diet HM (AA) did the extended AA supplementation (Lys, methionine (Met), threonine (Thr)) enhance protein quality (72.8 ± 6.7) significantly (p = 0.004). Similar trends were observed in growing pigs. However, when the level of histidine (His) in diet SM (AA) was increased, feed protein quality (71.8 ± 1.3) was significantly (p < 0.001) improved indicating the importance of adequate His supply in diets with a complete substitution of SBM by the algae meal (SM) under study. AA efficiency data extend the possibilities to explain the observed responses on protein quality. When an adequate AA balancing in the diet is guaranteed, from nutritional point of view both of the alternative proteins may replace SBM in pig diets.
Black soldier fly (Hermetia illucens) meal is a potential alternative to fishmeal and plant proteins in diets for farmed fish since it can be produced on organic waste substrates, requires little energy and water inputs and contains high levels of essential amino acids. Recent studies have partially replaced fishmeal with black soldier fly meal, however, research on their impact on gut microbiota of fish is limited. In a five week experiment, juvenile rainbow trout (Oncorhynchus mykiss) were fed either a reference diet based on fishmeal or three diets with 30% inclusion of black soldier fly meals in the form of pre-pupae, larvae or defatted-larvae. The combined luminal content and mucosa were collected from the distal intestine of three fish per tank with four tanks per diet (n = 12) and 16S rRNA gene amplicons were sequenced using the Illumina MiSeq platform. Feeding the insect-based diets increased the alpha-diversity of bacteria and abundance of lactic acid bacteria, which may be due to the addition of dietary chitin. Compared with fishmeal, feeding insects resulted in higher abundance of phyla Firmicutes and Actinobacteria with lower abundance of Proteobacteria. Fish fed the full-fat meals had higher abundance of Corynebacterium that was attributed to its ability to produce lipase and the high content of dietary lipids as a substrate. Bacillaceae was increased in fish fed both larvae diets and unchanged in the pre-pupae diet, which indicated that life-cycle stage of the insect influenced the gut microbiota. Based on these results, we found that feeding black soldier flies increased diversity and altered the composition of gut bacteria of rainbow trout, which were further influenced by life-cycle stage and lipid content of the insect meal.
We evaluated the effect of a diet containing insect meal and insect oil on nutrient utilization, tissue fatty acid profile and lipid metabolism of freshwater Atlantic salmon (Salmo salar). Insect meal and insect oil from black soldier fly larvae (Hermetia illucens, L.; BSF), naturally high in lauric acid (12:0), were used to produce five experimental diets for an eight‐week feeding trial. 85% of the dietary protein was replaced by insect meal and/or all the vegetable oil was replaced by one of two types of insect oil. A typical industrial diet, with protein from fishmeal and soy protein concentrate (50:50) and lipids from fish oil and vegetable oil (33:66), was fed to a control group. The dietary BSF larvae did not modify feed intake or whole body lipid content. Despite the high content of saturated fatty acids in the insect‐based diets, the apparent digestibility coefficients of all fatty acids were high. There was a decrease in liver triacylglycerols of salmon fed the insect‐based diets compared to the fish fed the control diet. This is likely due to the rapid oxidation and low deposition of the medium‐chain fatty acid lauric acid.
This study was conducted to evaluate the growth performance of broilers fed different levels of Hermetia illucens powder. A total of 400 broiler chicks (1-day old Arbor Acres) were fed commercial diets containing H. illucens powder at 0%, 0.1%, 0.5%, and 1% with four replicates (25 chicks per replicate), for 35 days. Weight gain in broilers fed diets containing different levels of H. illucens powder increased significantly at 28 and 35 days, compared with that of the control (p<0.05). However, feed intake and mortality showed no differences among the treatments as a function of time. At 21, 28, and 35 days, broilers fed different levels of H. illucens powder had lower feed conversion rates (p<0.05) than their counterparts fed the control diet. In conclusion, 0.5% H. illucens powder is the optimal level for improved weight gain and feed conversion.
We explored a new feed ingredient which can be replaced with conventional protein supplements such as fish meal and blood meal for young monogastric animals. Insect meal, especially larvae of black soldier fly (BSF, Hermetia illucens) can possibly be a high-quality protein source due to the fact that BSF larvae have high crude protein (36.1%) and crude fat (36.5%) concentration. In trial 1 for weaning pigs (initial BW: 6.75 ± 0.10 kg on average), 2 treatments were tested: control (0% BSF) vs. 2% BSF. Feeding BSF at 2% increased average daily gain (ADG; 414 vs. 334 g/d) and average daily feed intake (ADFI; 496 vs. 405 g/d) compared with control, respectively. In trial 2 for weaning pigs (initial BW: 6.32 ± 0.08 kg on average), we evaluated the possibility of replacing spray-dried plasma protein (SDPP) with BSF having 3 treatments: 4% SDPP + 0% BSF, 2% SDPP + 2% BSF, and 0% SDPP + 4% BSF. Although ADG decreased by feeding BSF at 2 or 4% compared with control (295 vs. 324 g/d), ADFI and feed conversion ratio (FCR) were not affected by feeding BSF regardless of dietary concentration. Despite the negative impact on ADG, feeding BSF at 2 or 4% resulted in formulation of cost-effective diets. In trial 3 with layer chicks (initial BW: 40.1 ± 0.16 g), 3 treatments were assessed having BSF at 0, 3, and 5%. Layer chicks fed BSF at 3 or 5% increased ADG compared to those without BSF (10.3 vs. 9.49 g/d). While dietary treatments did not influence ADFI, FCR was improved by feeding BSF at 3 or 5% compared with the diet at 0% BSF (1.88 vs. 1.99). Overall results on the series of 3 trials suggest that feeding BSF up to 5% to young monogastric animals can improve productive performance.
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.
This study investigated the effects of feeding Hermetia illucens larvae (0, 4, and 8%; HI0, HI4, and HI8 groups, respectively) on growth performance, carcass traits, and meat quality of finishing pigs. Results showed that the HI4 diet increased (P < .05) final body weight and average daily gain and decreased (P < .05) feed to gain ratio compared with HI0 and HI8 group. HI4 and HI8 diets increased (P < .05) loin-eye area, marbling scores, and inosine monophosphate content of longissimus thoracis(LT) compared with HI0 diet. The intramuscular fat content was greater (P < .05) in HI4 group than in the HI0 group. Furthermore, HI4 diet up-regulated (P < .05) lipogenic genes and MyHC-IIa mRNA levels in LT compared with HI0 diet. Our results indicated that dietary inclusion of H. illucens larvae has a beneficial impact on growth performance and meat quality, and the underlying mechanism may be due to the altered lipogenic potential induced by H. illucens larvae.
Black soldier fly larvae (BSFL; Hermetia illucens) are a suitable protein source for poultry. However the effect of live BSFL supplementation on growth performance and behaviour has never been demonstrated and quantified in turkeys. Wild turkeys eat insects during the first two weeks of life which is in contrast with commercially fed crumbs or pellets. Damaging pecking behaviour is a severe problem in turkeys. More lively diets may improve natural behaviour and decrease damaging pecking behaviour. The aim of the experiment was to stimulate natural behaviour of young non-beak treated turkeys by supply of live BSFL to avoid damaging pecking behaviour. Two treatments with seven replicates were studied in 14 floor pens (1.5 m2/pen and 20 turkeys per pen) from 0 to 35 days of age. Control groups were fed commercial diets and BSFL groups received live BSFL. The daily BSFL intake was calculated to be 10% of the expected daily feed intake (based on fresh weight) and dietary nutrient composition was adjusted in a way that control and BSFL groups were fed iso-nutritious. Daily feed intake and body weight gain of BSFL groups were significantly higher compared to control groups resulting in a significantly higher body weight at five weeks of age (2,190 vs 2,015 g; P=0.003) and a significantly lower feed conversion ratio. In the first week there was a tendency for more foraging related behaviour for the BSFL groups, but in the third and fifth week BSFL groups showed less foraging related behaviour compared to control groups. Provision of BSFL reduced aggressive pecking directed at the back and tail base at 5 weeks of age. Although the incidence of feather and skin damage was low, this type of damage tended to be lower in the BSFL groups.
Although results are partly inconsistent, it could be stated that dietary inclusion of defatted BSFL meal of 10% to 16% as soy replacement does not negatively affect the live weight and daily food intake of male broiler chicken, at least during the starter period. During the growing and finishing periods, lower levels have been recommended. The health status determined by blood marker analysis does not conclude detrimental effects of defatted BSFL (Dabbou et al., 2018; Altmann et al.,2018). For egg production, the dietary inclusion of 7.5% defatted BSFL meal as substitute for soy is reasonable and results into more uniform eggs with darker yolk that are more resistant and could result in less losses during the production and supply chain.
This research aimed at improving the fatty acid (FA) profile of Hermetia illucens larvae (HI) and evaluating the effects of their inclusion in growing broiler quails’ diets on the meat physicochemical quality, including detailed amino acid (AA) and FA profiles, sensory traits, and retail display. HI larvae were reared on two different substrates: layer mash (HI1) and 50:50 layer mash/fish offal (HI2). A total of 300 10-day-old quails were allocated to the three dietary groups (five replicates/each): a soybean meal-based diet was formulated (Control), and two other diets were formulated that included
either 10% HI1 or HI2. Quails were fed the experimental diets until slaughter. Diets were formulated to be isonitrogenous and isoenergetic. Breast meat quality was affected by the dietary treatments, which displayed different proximate compositions and AA and FA profiles. Meat physical quality, sensory profile, and retail display remained unaffected for the most part. Overall, results showed that it is possible to improve the FA profile of the HI-fed quails’ meat and thus lipid quality through substrate modulation of the HI’s diet.
This trial investigated the effect of the dietary inclusion of Hermetia illucens (H) and Tenebrio molitor (T) fats as alternative lipid sources for growing rabbits, and assessed the carcass characteristics; proximate composition; lipid peroxidation, and fatty acid profile of the meat, as well as consumer acceptance. At weaning, 200 crossbred rabbits (1051 ± 138 g initial body weight) were allotted to five isolipidic (4% dry matter (DM)) dietary treatments: a control diet (C) containing 1.5% of soybean oil, and four experimental diets in which soybean oil was partially (50%) or totally (100%) substituted by H (H50 and H100) or T (T50 and T100) fats. The carcass characteristics, the meat quality traits, and the consumer acceptance of the cooked meat were not affected. The fat content of Longissimus thoracis et lumborum muscle of the rabbits was 1.1% on average. In the case of rabbit fed the H diets (average of diets H50 and H100), the same muscles revealed a higher saturated fatty acid proportion (47.1% vs. 39.7% and 40.8%, respectively) and a lower polyunsaturated fatty acid proportion than the rabbits fed the C and T diets (average of diets T50 and T100) (26.5% vs. 31.7% and 29.7%) (p < 0.001). The meat of the rabbits fed the diets containing insect fat (average for H and T diets) was less susceptible to oxidation (0.24 vs. 0.39 mg malondialdehyde/kg meat in the C group; p < 0.01).
The effect of insect feed powder on the growth performance and economic evaluation of ducks was investigated. One hundred and twenty-old Pekin ducks were randomly assigned to two dietary treatments (0% and 1% Hermetia illucens powder) with three replicates of 20 birds each for 14-42 d. No significant (p>0.05) difference in growth performance between the control and 1% H. illucens powder was observed, except the feed conversion ratio (p<0.05), for the experimental period. The treatments with 1% H. illucens powder improved the economic indicators in comparison with the controls. Therefore, a diet supplemented with 1% H. illucens powder could significantly improve the feed conversion ratios and increase the economic indicators.
Feather pecking is a key welfare challenge in laying hen husbandry. Feeding of live Hermetia illucens larvae could provide a possible solution to reduce feather pecking in hens. This research investigates effects of dispensing live H. illucens larvae to non‐beak trimmed older laying hens on production performance, behavior and welfare. Control treatment hens were provided a commercial diet, while larvae treatment hens were provided live H. illucens larvae (using special dispenser) on top of a soy‐free diet. Feather condition, production performance and egg quality were measured during the initiation (67 weeks age) and termination (78 weeks age) of the trial. Behavior of birds was monitored using video recording. Feed conversion ratio, body weight gain and egg laying parameters were similar for both treatments. At termination of the trial, larvae‐fed hens exhibited better feather condition in comparison to control hens (p = 0.004). Behavioral observations indicated that larvae provision influenced the number of birds on floor during morning and afternoon hours. In conclusion, live H. illucens larvae could successfully replace soy in diets of older laying hens (in combination with local plant proteins). Provisioning of these insects also had a positive effect on the feather condition of laying hens with intact beaks.
The present study was conducted to investigate growth performance, carcass characteristics, short-chain fatty acids, fatty acid composition in abdominal fat, and serum parameters in broiler chickens fed diets containing corn oil, coconut oil, or black soldier fly larvae (BSFL) oil at the level of 50 g per kg of diet during the 30-day-feeding period. A total 450 one-dayold male broiler chicks (Ross 308) were randomly allocated to one of 3 dietary groups. Each treatment had 10 replicates with 15 chicks per replicate. Feed conversion ratio was decreased in the coconut and BSFL oil group compared with the corn oil group. Dietary BSFL oil increased ileal weight-to-length ratio at day 30 after hatch. Dietary BSFL oil increased significantly ileal branched-chain fatty acid (P, 0.05) and moderately total short-chain fatty acid in 15-day-old broilers (P, 0.074). At day 30, ileal propionate was highest in the coconut oil group but cecal propionate was highest (P, 0.05) in the BSFL oil group. Fatty acid composition of abdominal fat was affected by dietary fat sources. Especially, chickens fed diets containing coconut oil or BSFL oil had higher contents (P, 0.05) of saturated fatty acid being dominant in lauric and myristic acids compared with those fed on corn oil. On the other hand, the reverse trend was noted (P, 0.05) as to polyunsaturated fatty acids being dominant in corn oil compared with coconut oil and BSFL oil. Coconut oil vs. corn oil significantly increased total and high-density lipoprotein cholesterol. Finally, BSFL oil vs. corn oil significantly increased total antioxidant capacity in chickens. It is concluded that dietary BSFL oil improves feed conversion ratio and increases the incorporation of medium-chain fatty acids into abdominal fat pad and serum antioxidant capacity in broiler chickens.
Fast-growing broilers spend most their time inactive and are therefore prone to experience leg problems. Environmental enrichment which facilitates intrinsically motivated behaviours can potentially promote activity and reduce leg problems, thereby improving broiler welfare. A promising environmental enrichment method is the scattering of desired feed items, such as insects which are highly attractive to broilers. We studied the effect of providing live black soldier fly larvae (BSFL) scattered on the litter on broiler behaviour, leg health and performance. One-day-old male broilers were assigned to one of five treatments (eight pens/treatment, nine broilers/pen): a control without BSFL and four treatments with BSFL in different amounts (5% or 10% of estimated dietary dry matter intake; A5 and A10 respectively) and frequencies (two or four times a day; F2 and F4 respectively). All broilers were fed diets formulated to ensure a similar energy and nutrient intake. Broiler weight and leg health were determined on day 42. The behavioural time budget was determined weekly by observations for 7 h per day using 12-min scan sampling, and activity around larval provisioning was determined by 3-min scan sampling from 9 min before, until 30 min after larval provisioning on day 15/16, 29/30 and 40/41. Broilers in all larval provisioning treatments had a different behavioural time budget than controls, with higher levels of foraging behaviour, walking, standing idle and general activity during at least three of the five observation days (p<0.05 compared to controls). Generally, active behaviours were most profoundly increased in A10F4 broilers. Time spent active and in standing posture declined from week 4 onwards in A10F4, whereas for all other treatments this decline occurred already in week 2. Activity during 30 minutes after larval provisioning was higher for A10 than A5 treatments (p<0.05 for all days) but overall not affected by frequency of larval provisioning. Hock burn occurred less in A10 birds than in controls (p<0.05), and lameness occurred less in A10 and A5F4 birds than in controls (p<0.01). Only A10F2 birds had a lower final weight than controls (p<0.05). In conclusion, the largest amount combined with the highest frequency of larval provisioning applied in this study resulted in a prolonged increase in activity and better leg health, without significantly affecting broiler performance.
The present study aimed to investigate the effects of different inclusion levels of Hermetia illucens larvae meal on the growth performance, apparent nutrient digestibility, blood parameters, and gut morphology of weanling piglets. A total of 128 weanling piglets were randomly assigned to 4 dietary treatment groups. Full-fat H. illucens larvae meal was included at increasing levels (0, 1, 2, and 4 %; HI0, HI1, HI2, and HI4, respectively) in isonitrogenous and isoenergetic diets formulated for 2 feeding phases: I (from day 1–14) and II (from day 15–28). Each treatment consisted of 8 pens (replicates), with 4 pigs per pen. After 28 d of feeding, 8 piglets per treatment (n = 8) were slaughtered. Results showed that the body weight (BW) on day 14, average daily gain (ADG) from day 1–14, and the relative weight of the liver, pancreas, and small intestine had a linear increase (P < 0.05, maximum in HI2) in response to H. illucens larvae meal consumption, while the feed/gain (F/G) ratio from day 1–14 exhibited a linear and quadratic decrease (P < 0.05, minimum in HI2) in the response. Linear and quadratic decreases (P < 0.05, minimum in HI4) were detected for the crude protein and crude fat digestibility. Linear and quadratic (P < 0.05, maximum in HI2) were observed for the total protein and globulin concentrations, while a linear and quadratic (P < 0.05, minimum in HI2) effect was observed for the urea concentration. The triglyceride concentration showed a quadratic decrease (P < 0.05, minimum in HI2) in response to H. illucens larvae meal consumption. Linear and quadratic (P < 0.01) were observed for the IFN-γ (minimum in HI4) and IgA (maximum in HI2) concentrations. The HI2 diet also increased the IL-10 concentration compared with HI0 group (P < 0.05). Furthermore, the villus height in the jejunum of the piglets was higher in the HI2 group than in the HI0 group (P < 0.05). Collectively, our results indicated that feeding 2 % full-fat H. illucens larvae meal to partly replace fishmeal changed the host metabolism, immune status, and intestinal morphology of weanling piglets. These findings further increase our knowledge and provide novel information about the potential of H. illucens larvae meal as a suitable alternative fishmeal source for swing feeding.
A ten-week feeding trial on Monopterus albus (initial weight 24.02 ± 0.02 g) was conducted to evaluate effects of four isonitrogenous and isoenergetic diets in which different proportions of fish meal (0, 2.5 %, 5% and 7.5 %) were substituted with Hermetia illucens (HI) larvae meal, corresponding to dietary inclusion levels of 0 (FM), 5.26 % (HI5.26), 10.52 % (HI10.52) and 15.78 % (HI15.78). Compared with FM, weight gain rate and condition factor of M. albus and gumminess and adhesiveness of its muscle tissue were significantly increased in HI5.26 and HI10.52 groups (P < 0.05); whereas feed conversion ratio was markedly decreased in HI5.26 (P < 0.05), and expression of hepatic FASD2 and ME2 was significantly upregulated in HI5.26 (P < 0.05). Compared with FM, cohesiveness of muscle was significantly decreased in HI groups, but hardness of muscle and expression of hepatic FAS were remarkably upregulated in HI groups (P < 0.05); ACC and ME1 mRNA levels were significantly upregulated in HI10.52 (P < 0.05); CPT2 mRNA levels were significantly upregulated in HI5.26 and HI15.78 (P < 0.05); PPARγ, G6PD and HSL mRNA levels were significantly upregulated in HI10.52 and HI15.78 (P < 0.05). Springiness and chewiness of muscle, activity of intestinal lipasewere, serum indexes (glutamic oxalacetic transaminase, catalase, malondialdehyde), several gut bacterial indices (shannon, chao1, ACE, OTUs abundance of proteobacterias) and abundance of hepatic PPARα mRNA in HI15.78 were remarkably lower than those in FM (P < 0.05), while content of crude lipid, gut firmicutes and hepatic Dgat2 mRNA were significantly lower than FM (P < 0.05). Results showed that HI improved growth performance and balance of gut bacteria of M. albus when supplemented at a rate below 15.78 %, but negative effects on lipid metabolism were observed when HI was supplemented at excessive levels.
For successful prawn aquaculture, feeds should be based on readily consumed ingredients that promote survival and optimal growth performance. This pilot study investigates the rearing of juvenile Baltic prawn Palaemon adspersus. Two feeding trials were carried out for 60 days; both incorporated insect meals, the first one in fishmeal-based diets, whereas the second one in plant meal ones. Insect meals derived from larvae of Tenebrio molitor (TM), Hermetia illucens (HI) and Musca domestica (MD) were tested as feed ingredients. This study indicated that the inclusion of HI in fishmeal diets resulted in significantly higher growth performance and survival of the prawns, whereas the MD diet led to similarly high growth performance reducing significantly their survival. Growth performance was not affected by the insect inclusion in the plant-based diets, but survival was higher in the TM and HI inclusion diets. The inclusion of TM and HI resulted in higher protein and energy content of the prawns’ muscle when incorporated in fishmeal and plant meal diets respectively. No significant differences were observed in the activities of hepatopancreas’ amino acid-catabolizing enzymes. Concluding, the combinations fishmeal–HI and plant meal–TM can be used for the successful rearing of Baltic prawn.
In the present study, we aimed to assess the effect of dietary black soldier fly oil (BSFO) enriched with n-3 highly unsaturated fatty acids (HUFA) on growth performance, lipid metabolism, inflammation and related gene expression in juvenile mirror carp (Cyprinus carpio var. Specularis). Triplicate cages of juvenile mirror carp were fed one of five isonitrogenous and isolipidic diets for 8 weeks. The control diet contained 25 g kg−1 soybean oil (SO), which was 25%, 50%, 75% or 100% replaced with an n-3HUFA enriched BSFO. This enrichment was done by growing the insects on a by-product of microalgae oil production. The growth and nutrient utilization as well as many health parameters of the fish were significantly improved when fed a 50% or higher replacement of SO with the n-3 HUFA enriched BSFO. A replacement level at 50% or above led to a decreased intra-peritoneal fat index and adipocyte size, accompanied by relevant changes in gene expression. The same replacement levels also led to an improvement in the serum biochemical profile of the fish and showed indications of enhancing immune status. Gene expression results of the liver and head kidney indicates a less inflammatory state in fish fed more than a 50% replacement of SO with BSFO. Overall, this study showed that a 50–100% replacement of SO with this n-3 enriched BSFO positively influences the performance and health status of juvenile mirror carp.
The aim of the work was to assess the effect of dietary inclusion of meals derived from black soldier fly (BSF) larvae on the performance and carcass composition in broilers. The trial was carried out with Ross 308 broilers divided in three groups according to the formulated diets: control, receiving standard diet, DFBSFM (receiving 5% partially defatted BSF meal), and FFBSFM (receiving 5% full fat BSF meal during the growing-finishing period, 14 to 35 days of age). The performance parameters controlled included body weight, weight gain, feed intake, feed conversion ratio, as well as the growth rate for each week of the trial. At 35 days of age, 10 broilers from each group were slaughtered and subjected to carcass analysis. The inclusion of 5% DFBSFM and FFBSFM in the diet improved performance of the broilers at the age of 21 and 35 days. The carcass weight and dressing percentage were higher in the groups receiving the insect meals. The results indicate potential of the DFBSFM and FFBSFM to alter the carcass composition of the broilers. Their inclusion in the diet of the birds tended to increase the percentage of the breast cuts, whereas the thigh muscles significantly decreased. The results of the study suggest good prospective for further research with the examined BSF meals, for their application as feed components in broiler nutrition that will not have adverse effect on the carcass composition and quality.
Fast-growing broilers spend most their time inactive and are therefore prone to experience leg problems. Environmental enrichment that facilitates intrinsically motivated behaviours can potentially promote activity and reduce leg problems, thereby improving broiler welfare. A promising environmental enrichment method is the scattering of desired feed items, such as insects, which are highly attractive to broilers. We studied the effect of providing live black soldier fly larvae (BSFL) scattered on the litter on broiler behaviour, leg health and performance. One-day-old male broilers were assigned to one of five treatments (eight pens/treatment, nine broilers/pen): a control without BSFL and four treatments with BSFL provided from day 1 onwards in different amounts (5 % or 10 % of estimated dietary dry matter intake; A5 and A10 respectively) and frequencies (two or four times a day; F2 and F4 respectively). All broilers were fed diets formulated to ensure a similar energy and nutrient intake. Broiler weight and leg health were determined on day 42. The behavioural time budget was determined weekly by observations for 7 h per day using 12-min scan sampling, and activity around larval provisioning was determined by 3-min scan sampling from 9 min before, until 27 min after larval provisioning on day 15/16, 29/30 and 40/41. Broilers in all larval provisioning treatments had a different behavioural time budget than controls, with significantly higher levels of foraging behaviour, walking, standing idle and general activity during at least three of the five observation days (p < 0.05 compared to controls). The increase in activity was numerically highest and most long-term in A10F4 broilers. Time spent active and in standing posture declined from week 4 onwards in A10F4, whereas for all other treatments this decline occurred already in week 2. Activity during 30 min after larval provisioning was higher for A10 than A5 treatments (p < 0.05 for all days) but overall not affected by frequency of larval provisioning. Hock burn occurred less in A10 birds than in controls (p < 0.05), and lameness occurred less in A10 and A5F4 birds than in controls (p < 0.01). Only A10F2 birds had a lower final weight than controls (p < 0.05). In conclusion, the largest amount combined with the highest frequency of larval provisioning applied in this study resulted in the most prominent increase in activity and better leg health, without significantly affecting broiler performance. Further investigation into BSFL provisioning methods is required to determine the optimal method for achieving improved broiler welfare.
This study provides data on the environmental sustainability, economic profitability, and gastrointestinal tract development of Siberian sturgeon diets containing black soldier fly full‐fat larvae meal (BSFL) for a fish meal (FM) and fish oil (FO) replacement. BSFL was used at 5%, 10%, 15%, 20%, 25%, and 30% of the diet, replacing by up to 61.3% of FM and 95.4% of FO. BSFL positively affected the feed efficiency ratio, and lowered FM and FO usage per kg of fish gain. All the BSFL diets showed a sustainable fish‐in fish‐out (FIFO) ratio, which was lowered by up to 75% in comparison to the control. Economic assessment per kg of fish gain showed that the most lucrative variants were variants with 10% and 15% BSFL, it finds a mode of action in improvements of the gastrointestinal tract development, including increased pyloric caeca and proximal intestine shares and enhanced villus height and area. Thus, in Siberian sturgeon, BSFL may be used not only as an FM and FO replacer but also as a functional material due to its feed utilization and beneficial health effects, which are reflected in its high sustainability and favourable economics.
For the first time, this review briefly summarizes the data of foreign and Russian studies on the use of flour from larvae and prepupae of the Black Soldier fly (Hermetia illucens) as an ingredient in the diet of feed for growing weaned piglets and pigs. This type of larvae is characterized by a high content of amino acids and fatty acids in its composition, which makes them a valuable ingredient in feed for raising animals, birds and fish. It is shown that Flour and fat from Hermetiaillucens larvae are promising alternative ingredients to traditional feed protein sources (fish meal and soybean meal) for raising piglets and pigs. It was revealed that in small dosages the addition of insect larvae flour promotes an increase in the biomass of animals, has a positive effect on the intestinal microbiota and improves the bloodbiochemical parameters of experimental animals.