Cafeteria-Type Feeding of Chickens Indicates a Preference for Insect (Tenebrio molitor) Larvae Meal

Use of Acheta domesticus meal as a full soybean substitute in the feeding of slow-growing chicks

Sustainable poultry meat production involves the use of slow-growing chick strains and the utilization of new protein sources as an alternative to the current monopoly of soybean meal. In this scenario, a study was conducted to assess the effect of replacing soybean meal with domestic cricket (Acheta domesticus) meal on the developing cycle of slow-growing chicks. To this end, a total of 128 one-day-old male chicks (Colorield) were randomly assigned into 16 experimental units, each consisting of 8 chicks, which in turn were grouped into 2 groups fed isoproteic and isoenergetic diets in which the protein source differed: the control group (C) fed soybean meal and the Acheta group (AD) fed Acheta domesticus insect meal as the main protein source. Chicks were slaughtered at 95 d of age. Three different diets (F1, F2 and F3) were used for each experimental group according to the nutritional needs of the birds during their growth. The F1 diet (1-29 d) resulted in higher feed and water intake and higher body weight gain for group C, but a lower feed conversion rate. On the contrary, during F2 (29-60 d) no differences in productive performances were observed between the 2 groups, except for a higher water intake for group C. Finally, during the period corresponding to diet F3 (60-95 d) there were only differences in feed intake, which was higher for the AD group. In conclusion, the substitution of soybean meal for Acheta domesticus meal caused a decrease in feed intake during the first month and consequently a lower body weight. During the first 4 weeks of life of the chicks, a partial replacement of soybean meal may be recommended, since high inclusions of A. domesticus meal in this period seem to be detrimental in young chicks. Given the absence of relevant differences in productive performances between both groups, it could be concluded that the use of A. domesticus cricket meal can be a potential protein alternative to soybean meal.

Evaluation of full-fatted and hydrolysate mealworm (Tenebrio molitor) larvae as a substitute for spray-dried plasma protein diet in weaning pigs

The goal of this experiment was to examine the effect of dietary inclusion of full-fatted mealworm larvae (FFML) or hydrolysate mealworm larvae (HML) (Tenebrio molitor) as a substitute for spray-dried plasma protein (SDPP) as a protein source on the performance and immune status of nursery pigs. A total of 150 crossbred piglets (6.48 ± 0.01 kg) were randomly allocated to 1 of 3 dietary groups in two feeding phases: phase 1 (Days 0-14) and phase 2 (Days 15-35). Each treatment had 10 replicates with 5 pigs per replicate. The nutritious diets were: Phase 1: SDPP-CON (control-basal diet) + 6% SDPP diet; FFML-CON + 3% SDPP and 3% FFML diet; HML-CON + 3% SDPP and 3% HML diet. Phase 2: SDPP-CON (basal diet) + 3% SDPP diet; FFML-CON + 3% FFML diet; HML-CON + 3% HML diet. The inclusion of FFML or HML diet did not show significant difference but had a comparable effect as that of standard control diet containing SDPP on the growth performance, nutrient digestibility and faecal score throughout the trial. In comparison to pigs fed SDPP diet, pigs fed FFML and HML diets had similar and/or higher (p < 0.05) serum immunoglobulin (IgA and IgG) concentration at the end of phase 1 and 2. The result of the present study indictes that SDPP would be partially or fully replaced with FFML or HML to suit weaning pigs diet.

Effects of increasing levels of whole Black Soldier Fly (Hermetia illucens) larvae in broiler rations on acceptance, nutrient and energy intakes and utilization, and growth performance of broilers

Meal of black soldier fly larvae (BSFL), which requires extraction of protein and fat, is a novel protein source for poultry, while unprocessed whole BSFL could even directly be fed to chickens. Newly hatched Ross-308 chicks (n = 252) received whole BSFL at 10% (L10), 20% (L20), or 30% (L30) of voluntary feed intake (FI) of control chickens (CON) that received no BSFL but only age-specific diets (n = 63 birds / group) for 42 days (d). Acceptance and nutrient and energy intake of birds by BSFL and FI were calculated. Plasma metabolites were measured using an automatic enzymatic analyzer and immunoglobulins with ELISA. Depending on the variable, data were analyzed using ANOVA or repeated measures ANOVA to address treatment, time and interaction effects. Birds consumed all offered larvae. With the exception of d1, time spent by birds eating their daily portion of larvae (TSL, min/pen) did not differ among the larvae supply groups (P = 0.982). The L10 had a higher larvae eating rate (LER) that is, speed of larvae intake than did L20 and L30 (P < 0.05), implying increased competition for less available BSFL. The ratio of LER to feed eating rate (FER) was greater than 50 fold change difference (FCD), indicating a strong interest of chickens in BSFL over regular feed. Whole BSFL intake up to 30% of voluntary FI did not adversely affect broiler growth (P > 0.05). The L30 had lower total dry matter and metabolizable energy intakes (P < 0.05), although total fat intake was higher in L30 than in CON (P < 0.05). Compared with CON, 30% whole BSFL increased dietary protein-to-energy ratios, plasma uric acid and serum alkaline phosphatase concentrations (P < 0.05). We conclude that whole BSFL can be included in broiler rations up to 20% without negatively affecting growth performance and nutrient conversion efficiency, whereas a higher proportion is associated with lower protein utilization efficiency, possibly due to lower total energy intake.

Suitability of Hermetia illucens larvae meal and fat in broiler diets: effects on animal performance, apparent ileal digestibility, gut histology, and microbial metabolites

Background

The possibility of partially replacing soybean meal (SBM) with Hermetia illucens (HI) defatted larvae meal in broiler nutrition has frequently been suggested. For sustainability reasons, however, the larvae fat produced during defatting should also be used and could be particularly beneficial regarding gut health due to its fatty acid composition. To evaluate the suitability of HI larvae as protein and fat source, a 2 × 3 factorial arrangement with two types of protein, i.e. SBM (S) or SBM and 15% of its crude protein replaced by HI larvae meal (L), and three levels of fat sources, namely 0 (0 L), 50% (50 L) or 100% HI larvae fat (100 L) at the expense of soybean oil was applied.

Results

In the starter phase, an interaction showed higher body weight (BW), average daily gain (ADG) and improved feed conversion ratio (FCR) if 50% or 100% HI larvae fat was fed with HI larvae meal. Moreover, BW, ADG and FCR improved when feeding HI larvae meal as protein source. Additionally, we observed an increased average daily feed intake in the grower, finisher, and overall phase in the L groups and an improved FCR in 0 L compared to 50 L groups during the overall period. Regarding apparent ileal digestibility, HI larvae meal feeding increased dry matter, organic matter, and fat digestibility. Feeding HI larvae meal as protein source decreased the concentrations of agmatine, spermidine, spermine and ammonia in the caecal digesta, whereas fat source affected agmatine with higher concentrations in 50 L compared to 0 L in the colonic digesta. In contrast, caecal ethanolamine concentrations increased in HI larvae meal groups compared to SBM. Caecal butyric acid concentrations decreased with HI larvae meal feeding. An interaction was found for the jejunal villus area, being higher in L + 100 L compared to S + 100 L. Furthermore, L groups had greater villus width.

Conclusions

A partial replacement of SBM with HI larvae meal and soybean oil with HI larvae fat in broiler diets without impairing animal performance or gut health seems possible. Feeding HI larvae meal affected broiler performance positively in the starter phase and improved apparent ileal digestibility.

Performance of Slow-Growing Chickens Fed with Tenebrio molitor Larval Meal as a Full Replacement for Soybean Meal

Insect larval meal is an increasingly common protein source in poultry systems. In this study, the effect of replacing soybean meal with Tenebrio molitor larval meal on the performance of slow-growing chickens was assessed. A total of 128 one-day-old chickens (Colorield) were randomly divided into a control group (C) (n = 64), fed with soybean meal, and an experimental group (TM) (n = 64), fed with T. molitor larvae meal. The chicks were slaughtered after 95 days. Three different isoenergetic and isoproteic diets (F1, F2 and F3) were used for each group. The F1 diet resulted in higher body weight gain and higher feed and water intakes in group C, but a lower feed conversion ratio. Contrarily, diets F2 and F3 did not produce differences in the studied parameters between the two groups, except for body weight gain in the case of diet F2, which was highest in group C. Therefore, weight gain and feed and water intakes were significantly higher in group C, but there were no differences in feed conversion ratio or live weight. In conclusion, the total replacement of soybean meal with T. molitor larvae meal resulted in a reduction in feed intake and a consequent reduction in weight. During this period, partial rather than total substitution may be recommended.