Nutritional value of a partially defatted and a highly defatted black soldier fly larvae (Hermetia illucens L.) meal for broiler chickens: apparent nutrient digestibility,apparent metabolizable energy and apparent ileal amino acid digestibility

Background: The study aimed to determine the apparent total tract digestibility coefficients(ATTDC) of nutrients, the apparent metabolizable energy(AME and AMEn) and the amino acid(AA) apparent ileal digestibility coefficients(AIDC)of a partially defatted(BSFp) and a highly defatted(BSFh) black soldier fly larvae meal. The experimental diets were: a basal diet and two diets prepared by substituting 250 g/kg(w/w) of the basal diet with BSFp or BSFh, respectively.Results: Significant differences were found between BSFp and BSFh meals for ATTDC of the nutrients: BSFp resulted more digestible than BSFh, except for ATTDC of CP which did not differed between meals, while a statistical trend was observed for ATTDC of DM and EE. The AME and AMEn values were significantly(P < 0.05) different between the two BSF meals, with higher levels for BSFp(16.25 and 14.87 MJ/kg DM, respectively). The AIDC of the AA in BSFp ranged from 0.44 to 0.92, while in BSFh they ranged from 0.45 to 0.99. No significant differences were observed for the AA digestibility(0.77 and 0.80 for BSFp and BSFh, respectively), except for glutamic acid, proline and serine that were more digestible in the BSFh meal(P < 0.05).Conclusions: Defatted BSF meals can be considered as an excellent source of AME and digestible AA for broilers with a better efficient nutrient digestion. These considerations suggested the effective utilization of defatted BSF larvae meal in poultry feed formulation.

Partially defatted black soldier fly larva meal inclusion in piglet diets: effects on the growth performance, nutrient digestibility,blood profile, gut morphology and histological features

Background:The aim of this trial was to investigate the effects of different inclusion levels of a partially defatted black soldier fly (BSF,Hermetia illucens L.) larva meal on the growth performance,nutrient digestibility,blood profile,gut morphology and histological features of piglets.A total of 48 newly weaned piglets were individually weighed (initial body weight (IBW):6.1 ± 0.16 kg) and randomly allocated to 3 dietary treatments (4 boxes as replicates/treatment and 4 animals/box).BSF larva meal was included at increasing levels (0% [BSF0],5% [BSFS] and 10% [BSF10]) in isonitrogenous and isoenergetic diets formulated for two feeding phases:Ⅰ (from d 1 to d 23) and Ⅱ (from d 24 to d 61).The weight gain (WG),average daily gain (ADG),average daily feed intake (ADFI) and feed conversion ratio (FCR) were calculated for each feeding phase and for the whole trial.The haematochemical parameters and nutrient digestibility of the piglets were also evaluated.A total of 3 piglets per box were slaughtered on d 61 and the slaughtered piglets were submitted to morphometric investigations and histopathological examinations.Results:No overall significant differences were observed for growth performance (P > 0.05),except for the ADFI of phase Ⅱ,which showed a linear response to increasing BSF meal levels (P < 0.05,maximum for the BSF10 group).Dietary BSF meal inclusion did not significantly influence the blood profile,except as far as monocytes and neutrophils are concerned,and these showed a linear and quadratic response,respectively,to increasing BSF meal levels (P < 0.05,maximum for the BSF10 and BSF5 groups,respectively).On the other hand,the nutrient digestibility,gut morphology and histological features were not affected by dietary BSF meal inclusion (P > 0.05).Conclusions:The obtained results show that a partially defatted BSF larva meal can be used as a feed ingredient in diets for weaned piglets without negatively affecting their growth performance,nutrient digestibility,blood profile,gut morphology or histological features.

Black soldier fly defatted meal as a dietary protein source for broiler chickens:Effects on growth performance,blood traits,gut morphology and histological features

Background: The present study has evaluated the effects of different inclusion levels of a partially defatted black soldier fly(Hermetia illucens L.; HI) larva meal on the growth performance, blood parameters and gut morphology of broiler chickens. A total of 256 male broiler chickens(Ross 308) were reared from d 1 to d 35 and assigned to4 dietary treatments(8 replicates/treatment and 8 birds/replicate). HI larva meal was included at increasing levels(0, 5%, 10% and 15%; HI0, HI5, HI10 and HI15, respectively) in isonitrogenous and isoenergetic diets formulated for 3 feeding phases: starter(1–10 d), growing(10–24 d) and finisher(24–35 d). Two birds per pen were slaughtered at d 35 and morphometric investigations and histopathological alterations were performed.Results: The live weight(LW) showed linear and quadratic responses to increasing HI larva meal(maximum for HI10 group). Average daily gain(ADG) showed a linear and quadratic responses to HI meal(maximum for HI10 group) during starter and growing periods. A linear decrease was observed for ADG during the finisher period. The daily feed intake(DFI) showed a linear and quadratic effect during the starter period(maximum for HI10 group).Linear and quadratic responses were observed for the feed conversion ratio(FCR) in the growing period and for the whole period of the experiment. The FCR showed a linear response in the finisher period(maximum for HI15).No significant effects were observed for the blood and serum parameters, except for the phosphorus concentration,which showed linear and quadratic responses as well as glutathione peroxidase(GPx) activity, the latter of which showed a linear response. The HI15 birds showed a lower villus height, a higher crypt depth and a lower villus height-to-crypt depth ratio than the other groups.Conclusions: Increasing levels of dietary HI meal inclusion in male broiler chickens may improve the LW and DFI during the starter period, but may also negatively affect the FCR and gut morphology, thus suggesting that low levels may be more suitable. However, no significant effects on the haematochemical parameters or histological findings were observed in relation to HI meal utilization.

Nutritional effects of the dietary inclusion of partially defatted Hermetia illucens larva meal in Muscovy duck

Background: The present work is aimed at evaluating the effect of different inclusion levels of a partially defatted black soldier fly(Hermetia illucens,L.;HI) larva meal for ducks.A total of 192 female 3-day-old Muscovy ducklings(Cairina moschata domestica,Canedins R71 L White,Grimaud Freres Selection,France) were divided into 4 groups,assigned 4 different dietary treatments(6 replicates/treatment and 8 birds/replicate) and reared from 3 to 50 days of age.HI larva meal was included at increasing levels(0,3%,6% and 9%,HI0,HI3,HI6 and HI9,respectively) in isonitrogenous and isoenergetic diets formulated for 3 feeding phases: starter(3–17 days of age),grower(18–38 days of age) and finisher(39–50 days of age).The growth performance and apparent total tract digestibility were evaluated during the trial using titanium dioxide as an inert marker(0.3% of inclusion).At 51 days of age,two birds per pen were slaughtered and histomorphological investigations were performed.Results: The live weight and average daily gain showed a quadratic response to increasing HI meal in the grower period(minimum corresponding to the HI6 group).No effects of dietary inclusion levels were observed for the daily feed intake or feed conversion ratio.The apparent dry matter and organic matter digestibility were not affected by the dietary treatment.A linear decrease was observed for the crude protein apparent digestibility in the starter period(minimum for the HI9 groups).The ether extract apparent digestibility increased linearly during the grower and finisher periods(minimum for the HI0 group).The morphometric indices were not influenced by the dietary treatments.Conclusions: The inclusion of up to 9% of HI partially defatted larva meal in the diet of ducks did not cause any effect on growth performance,as well as the apparent digestibility.Moreover,dietary HI inclusion preserved the physiological intestinal development.

Black soldier fly and gut health in broiler chickens:insights into the relationship between cecal microbiota and intestinal mucin composition

Background:The relationship between diet and intestinal microbiota and mucin composition appears to be fundamental for poultry gut health.The effects of insect meal(whose role as alternative feed ingredient is now well recognized)on gut microbiota and mucin composition have recently been reported in Tenebrio molitor-fed free-range and broiler chickens,but no data are currently available for Hermetia illucens(HI)-fed broilers.The present study evaluated the effects of dietary HI meal inclusion on cecal microbiota and intestinal mucin composition of broiler chickens.Results:A total of 256 male broiler chickens were allotted to 4 dietary treatments(control diet[C]and 5%,10%and 15%HI meal inclusion,with 8 replicate pens/treatment and 8 birds/pen)and slaughtered at 35 d of age(2 animals/pen,16 birds/diet).The cecal microbiota assessment by 16S rRNA amplicon based sequencing showed lower alpha diversity in HI15 chickens(Shannon,P<0.05)and higher beta diversity(Adonis and ANOSIM,P<0.001)in birds fed HI diets than C.Furthermore,HI15 birds displayed significant increase of the relative abundance of Proteobacteria phylum(False Discovery Rate[FDR]<0.05)when compared to HI10.L-Ruminococcus(Ruminococcus from Lachnospiraceae family),Faecalibacterium,Blautia and Clostridium genera were found to be characteristic of HI5 cecal microbiota(FDR<0.05),while broiler chickens fed HI10 and HI15 diets were characterized(FDR<0.05)by Lactobacillus and Ruminococcus(HI10)and Bacteroides,Roseburia and Helicobacter genera(HI15).Periodic-acid Schiff,Alcian Blue pH 2.5 and high iron diamine staining on small and large intestine also demonstrated lower mucin staining intensity in the intestinal villi of HI10 and HI15 birds than C(P<0.05).Conclusions:Dietary HI meal utilization at low inclusion levels(i.e.,5%)positively influenced either the cecal microbiota or the gut mucin dynamics in terms of selection of potentially beneficial bacteria and increase in villi mucins.However,high inclusion levels(in particular the 15%)may have a negative influence in terms of partial reduction of microbial complexity,reduction of potentially beneficial bacteria,selection of bacteria with mucolytic activity and decrease in villi mucins.

Effect of dietary supplementation with insect fats on growth performance,digestive efficiency and health of rabbits

Background: The present work aimed at evaluating the effect of the dietary replacement of soybean oil(S) by two types of insect fats extracted from black soldier fly larvae(H, Hermetia il ucens L.) and yel ow mealworm larvae(T, Tenebrio molitor L.) on growth performance, nutrient digestibility, blood parameters, intestinal morphology and health of growing rabbits.Methods: At weaning, 200 crossbred rabbits(36 days old) were allotted to five dietary treatments(40 rabbits/group): a control diet(C) containing 1.5% of soybean oil and four experimental diets where soybean oil was partially(50%) or totally(100%) substituted by H(H50 and H100) or T(T50 and T100) fats. Total tract digestibility was evaluated on 12 rabbits per treatment. The growth trial lasted 41 d and, at slaughtering(78 days old), blood samples were collected from 15 rabbits per treatment, morphometric analyses were performed on duodenum, jejunum and ileum mucosa,and samples of liver, spleen and kidney were submitted to histological evaluation.Results: No difference was observed between the control and the experimental groups fed insect fats in terms of performance, morbidity, mortality and blood variables. The addition of H and T fats did not influence apparent digestibility coefficients of dry matter, protein, ether extract, fibre fractions and gross energy. Gut morphometric indices and organ histopathology were not affected by dietary inclusion of H and T fats.Conclusions: H and T fats are suitable sources of lipid in rabbit diets to replace soybean oil without any detrimental effect on growth performance, apparent digestibility, gut mucosa traits and health.

Effects of dietary Hermetia illucens meal inclusion on cecal microbiota and small intestinal mucin dynamics and infiltration with immune cells of weaned piglets

Background: The constant interaction between diet and intestinal barrier has a crucial role in determining gut health in pigs. Hermetia illucens(HI) meal(that represents a promising, alternative feed ingredient for production animals) has recently been demonstrated to influence colonic microbiota, bacterial metabolite profile and mucosal immune status of pigs, but no data about modulation of gut mucin dynamics are currently available. The present study evaluated the effects of dietary HI meal inclusion on the small intestinal mucin composition of piglets, as well as providing insights into the cecal microbiota and the mucosal infiltration with immune cells.Results: A total of 48 weaned piglets were randomly allotted to 3 dietary treatments(control diet [C] and 5% or10% HI meal inclusion [HI5 and HI10], with 4 replicate boxes/treatment and 4 animals/box) and slaughtered after61 days of trial(3 animals/box, 12 piglets/diet). The cecal microbiota assessment by 16 S r RNA amplicon based sequencing showed higher beta diversity in the piglets fed the HI-based diets than the C(P < 0.001). Furthermore,the HI-fed animals showed increased abundance of Blautia, Chlamydia, Coprococcus, Eubacterium, Prevotella,Roseburia, unclassified members of Ruminococcaceae, Ruminococcus and Staphylococcus when compared to the C group(FDR < 0.05). The gut of the piglets fed the HI-based diets showed greater neutral mucin percentage than the C(P < 0.05), with the intestinal neutral mucins of the HI-fed animals being also higher than the sialomucins and the sulfomucins found in the gut of the C group(P < 0.05). Furthermore, the piglets fed the HI-based diets displayed lower histological scores in the jejunum than the other gut segments(ileum [HI5] or ileum and duodenum [HI10], P < 0.05).Conclusions: Dietary HI meal utilization positively influenced the cecal microbiota and the small intestinal mucin dynamics of the piglets in terms of selection of potentially beneficial bacteria and preservation of mature mucin secretory architecture, without determining the development of gut inflammation. These findings further confirm the suitability of including insect meal in swine diets.

Dietary inclusion of a partially defatted black soldier fly(Hermetia illucens)larva meal in low fishmeal-based diets for rainbow trout(Oncorhynchus mykiss)

Background:Recent investigations highlighted that Hermetia illucens(BSF)larva meal can be a valuable alternative protein source for aquafeed production.In this study,in substitution of fishmeal,we used increasing inclusion levels of a partially defatted BSF larva meal in low fishmeal-based diets for rainbow trout(Oncorhynchus mykiss Walbaum)and we evaluated the related implications in terms of growth performance,physical characteristics,proximate and fatty acid(FA)compositions of the fillets,gut and liver histology,and diet digestibility.In a 131-day trial,576 fish(100.1±9.29 g)were randomly allotted to 24 tanks(24 fish/tank,4 replicates/treatment).Six experimental diets were produced to have partial replacement of fishmeal(0,10%,20%,30%,40%and 50%)by increasing levels of BSF meal(0%[BSF0],3%[BSF3],6%[BSF6],9%[BSF9],12%[BSF12]and 15%[BSF15]on as fed basis,respectively).Results:No differences were observed among the treatments for all the considered growth performance parameters.The viscero and hepato-somatic indexes showed significant differences among the treatments,with the highest values observed in the BSF15 group.No differences were recorded in terms of fillet’s physical characteristics,dry matter(DM),crude protein(CP)and ether extract(EE)contents.Total saturated and monounsaturated FA increased,while polyunsaturated FA(particularly n-3 FA)decreased while increasing the HI meal inclusion in the diet.Histopathology of liver and gut was not affected,whereas,in posterior gut,villi were higher in BSF6 and BSF9 compared to BSF3 fish.The apparent digestibility of DM,CP,EE and gross energy did not vary among the treatments.Conclusions:These results suggest that a partially defatted BSF meal could be included up to 15%in low fishmeal-based diets for rainbow trout with no adverse effects on growth performance,fillet’s physical characteristics,gut and liver health,and diet digestibility.On the contrary,the fillet FA composition worsened while increasing the level of BSF meal in the diet.

Dietary Supplementation of Oregano and Sage Dried Leaves on Performances and Meat Quality of Rabbits

The aim of this research was to evaluate the dietary supplementation 1% （w/w） of oregano and sage dried leaves on performances and meat quality of broiler rabbits. A feeding trial, which lasted 48 d, was carried out on 105 male Bianca Italiana rabbits randomly divided in seven groups and fed ad libitum. At the end of the trial ten animals per group were slaughtered and samples of dorsal muscle were taken in order to perform laboratory analysis. Mortality rate did not statistically differ between groups. Growth performances of animals fed diets supplemented with aromatic plants were higher （P〈0.05） than those of animals of control group, whereas carcass parameters were not affected by treatments excepting for the slaughter weight that showed the same trend as growth performances. Meat quality traits, oxidative lipid stability and fatty acid proifle were not inlfuenced by aromatic plant supplementation. In conclusion, oregano and sage in form of dried leaves can be used in rabbit without adverse effects on performance, carcass characteristics and meat quality traits.

Defatted black soldier fly (Hermetia illucens) in pikeperch (Sander lucioperca) diets: Effects on growth performance, nutrient digestibility, fillet quality, economic and environmental sustainability

The use of insect meal in aquafeed formulations has recently gained attention.Detailed knowledge about the inclusion levels for pikeperch(Sander lucioperca),a promising candidate for intensive aquaculture in Europe remains,however,fragmented.In the present study,4 isoproteic(45%dry matter)and isoenergetic(21 MJ/kg)diets were formulated,including a control diet(H0)containing 30%fishmeal(FM)on an as-fed basis and the other 3 diets in which FM protein was replaced by defatted black soldier fly(Hemetia illucens)meal(HIM)at 25%,50%,and 100%(diet abbreviation H9,H18 and H36,corresponding to an inclusion level of 9%,18%and 36%,respectively).The feeding trial was performed in triplicate groups of 50 juvenile pikeperch(mean weight,68.7 g)fed with experimental diets for 84 d during which the growth performance,nutrient digestibility,fillet quality and economic and environmental sustainability of rearing pikeperch were evaluated.Our findings indicated that pikeperch in H0,H9,and H18 groups displayed better results regarding growth performance indices,except for survival rate where no significant difference among groups was recorded(P?0.642).A significantly lower organ-somatic index,including hepatosomatic,viscerosomatic and perivisceral fat index,was found in fish in H18 groups than other groups(P<0.05).Inclusion of HIM affected the digestibility of the nutrients and resulted in an almost linear reduction in the apparent digestibility coefficient of dry matter and protein.Concerning the fillet quality,dietary HIM negatively affected the protein and ash contents of the fish fillets,while the crude fat remained unchanged.Dietary HIM did not significantly modify total saturated,monounsaturated and polyunsaturated fatty acids in the fillets of fed pikeperch(P>0.05)but did reduce total n-3 fatty acids(P?0.001)and increased total n-6(P<0.001).Increasing inclusion levels of HIM reduced the environmental impacts associated with fish in-to-fish out ratio but entailed heavy burdens on energy use and eutrophication.Low and moderate inclusion levels of HIM did not negatively affect land use and water use compared to an HIM-free diet(P>0.05).The addition of HIM at a level as low as 9%elicited a similar carbon footprint to that of the control diet.The economic conversion ratio and economic profit index were negatively affected at increased insect meal inclusion levels.This study has shown that the incorporation of HIM in feed formulations for pikeperch is feasible at inclusion levels of 18%without adverse effects on growth performance parameters.The feasibility also highlighted the environmental benefits associated with land use and marine resources required to produce farmed fish.