Productive performance, egg-related indices, blood profiles, and interferon-Ɣ gene expression of laying Japanese quails fed on Tenebrio molitor larva meal as a replacement for fish meal

Effect of the rearing diet on gene expression of antimicrobial peptides in Hermetia illucens (Diptera: Stratiomyidae)

Insect proteins have been proposed for human and animal food production. Safeguarding the health status of insects in mass rearing allows to obtain high-quality products and to avoid severe economic losses due to entomopathogens. Therefore, new strategies for preserving insect health must be implemented. Modulation of the insect immune system through the diet is one such strategy. We evaluated gene expression of two antimicrobial peptides (one defensin and one cecropin) in Hermetia illucens (L.) (Diptera: Stratiomyidae) reared on different diets. Analyses were performed on prepupae and 10-day-old larvae reared on cereal- and municipal organic waste-based diets and on only prepupae reared on a cereal-based diet supplemented with sunflower, corn, or soybean oil. The inclusion of sunflower oil at different points in the cereal-based diet was also evaluated. Moreover, diet-driven differences in the inhibitory activity of the hemolymph were tested against Escherichia coli DH5α and Micrococcus yunnanensis HI55 using diffusion assays in solid media. Results showed that a municipal organic waste-based diet produced a significant overexpression of antimicrobial peptides only in prepupae. Inclusion of vegetable oils caused an upregulation of at least one peptide, except for the corn oil. Higher expression of both genes was observed when sunflower oil was added 5 days before pupation. All hemolymph samples showed an inhibitory activity against bacteria colonies. Our results suggest that municipal organic waste-based diet and vegetable oil-added diet may successfully impact the immune system of H. illucens. Such alternatives may also exist for other species of economic interest.

Low inclusion levels of Tenebrio molitor larvae meal in laying Japanese quail (Coturnix japonica, Gould, 1837) diet improve the intestinal morphometry, enzymatic activity and caecal short chain fatty acids profile

One hundred twenty, 12 weeks old laying Japanese quails (JQ) were equally divided into 4 groups (6 replicates of 5 birds/group). The control group (CON) fed a corn-soybean diet; TML1.4, TML2.8, and TML5.6 groups fed a diet where a Tenebrio molitor larvae meal (TML) was included at 1.4, 2.8, and 5.6%, respectively. The trial lasted 54 days. The villi height (VH) and the crypt depth (CD) linearly decreased from the control to the TML5.6 group (P < 0.01) in the duodenum, while an opposite trend was observed for the Ab+ mucous cells count (P < 0.01). The highest VH/CD ratio was found in the TML1.4 group (P < 0.01). In the jejunum a lower VH was observed in the TML1.4 compared to the CON group; the Ab+ mucous cells increased (P < 0.01) according to the increase of the TM inclusion in the diet, while the highest VH/CD ratio (P < 0.01) was recorded in the TML2.8 group. In the duodenum only the L-ANP has been affected by TML (P < 0.001), with a quadratic and linear effect. The L-ANP is affected by the dietary treatment in the jejunum (P < 0.05), where showed a quadratic effect with the highest value in TML2.8. The % of butyric acid is maximized (P < 0.05) with the TML1.4 diet and that of the isobutyrate and valeric acids increased (P < 0.01) from TML1.4 to TML5.6. The use of TML at 1.4% in laying quail diets can be considered as a way to improve the intestinal health of the birds.

Low dietary inclusion levels of Tenebrio molitor larva meal slightly modify growth performance, carcass and meat traits of Japanese quail (Coturnix japonica)

BACKGROUND

Insect-derived proteins are a promising, valuable and permitted ingredient for poultry feed. However, more emphasis should be given to their effects on avian species different from chicken, such as quail (Coturnix coturnix), whose rearing represents an important activity. The present paper provides novel information about the impact of graded dietary levels of Tenebrio molitor (TM) larvae meal on quail growth and meat quality.

RESULTS

Four diets were formulated with graded inclusion levels of TM, namely 1.65, 3.3 and 6.6 g on 100 g feed (T1.65, T3.3, T6.6, respectively) to partially replace the conventional proteins of a control diet (C). A total of 192 birds were allotted to one of the groups and fed for 35 days. The inclusion of TM meal linearly increased feed conversion ratio, and decreased carcass and breast weight. Texture and water holding capacity of meat were linearly reduced with increasing TM in diet, while fatty acid composition was not affected. However, the meat from quails fed diets including TM was subject to greater thermal damage than the C group; hence further studies are encouraged.

CONCLUSION

TM meal inclusion at higher levels than 1.65% slightly impaired the growth performance of Japanese quails. Negligible effects on physical properties such as colour, texture, cooking loss and also on the fatty acid profile of the raw and cooked meat was found after including TM in quails' diet up to 3.3%. © 2022 Society of Chemical Industry.

In vivo performances, ileal digestibility, and physicochemical characterization of raw and boiled eggs as affected by Tenebrio molitor larvae meal at low inclusion rate in laying quail (Coturnix japonica) diet

A total of 120, twelve wk old female Japanese quails were divided into 4 groups (6 replicates of 5 birds each). The control group (CON) fed a corn-soybean diet; in the other 3 groups, Tenebrio molitor larvae meal (TML) replaced 5, 10, and 20% of the soybean protein (T5, T10, and T20). The laying performance and egg quality were studied for 54 d. The data were processed by a one-way ANOVA; the orthogonal contrast analysis was performed to test the linear, quadratic and cubic effects among the means. The laying rate and egg mass linearly decreased (P < 0.01) as the TML inclusion level in the diet increased. The egg weight and feed conversion ratio linearly increased from the control to T20 diet (P < 0.01) while the digestibility of dry matter, organic matter, and crude protein linearly decreased (P < 0.05). The albumen and yolk weight showed a linear increase (P < 0.01) due to dietary TML inclusion, while the eggshell weight showed the opposite (P < 0.05). The estimated activity of Δ9-desaturase (C16:0), Δ5+Δ6-desaturase on both polyunsaturated fatty acid n-6 and n-3 linearly increased (P < 0.05) as affected by dietary TML. The boiled yolk lightness (L*) showed higher values in T5 and T10 groups (quadratic contrast, P < 0.01). The yolk redness index (a*) showed lower values in T5 and T20 than control and T10 groups (cubic contrast, P < 0.01). The albumen L*, a*, and b* indexes showed a significant effect of the quadratic contrast (P < 0.05). In addition, the albumen b* index showed a significant effect of the cubic contrast (P < 0.01). The total lipids showed the highest values (cubic contrast, P < 0.05) in the T10 and T20 groups. The total monounsaturated fatty acids linearly increased (P < 0.05) according to the increase of dietary TML. The best inclusion level of defatted TML meal for laying quails seems to be 1.4% of diet, corresponding to the T5 diet.

Dynamic Analysis of Major Components in the Different Developmental Stages of Tenebrio molitor

The yellow mealworm, Tenebrio molitor, is an important resource insect with a high protein percentage that is widely farmed in many countries. In this study, the content dynamics for protein, fat, chitin, and other components in the whole development process of yellow mealworms were analyzed by sampling from different instars and combining with their growth conditions. The results of the component dynamic analyses in the different development stages showed that the percentages of protein, fat, and chitin were the highest in the larval stage, pupal stage, and adult stage, respectively. The results of amino acid composition dynamic analysis also indicated comparatively higher essential amino acids in the earlier instar (e.g., before the 9th instar) larvae. Therefore, we found that the earlier instar is better than the final instar as the insect farming harvest time. Furthermore, the larvae in the earlier instar consumed dramatically less feed and could effectively reduce the farming costs of insect farmers. This finding provides an alternative option to farm insects for different purposes and in an economic way.

Safety of Mealworm Meal in Layer Diets and their Influence on Gut Morphology

Simple Summary

There is limited research on the use of the mealworm meal in laying hens’ diets and effects on relative organ weights, caecum microbiota, ileum morphology and digesta viscosity. All these parameters can affect the performance of animals, i.e., the laying and quality of eggs. The mealworm meal is a relatively new feedstuff, where it is necessary to exclude a possible harmful effect. Insect products have a beneficial nutrient content, but there are issues of stability, shelf life, storage and contamination, which could, in the case of negative properties, affect the morphology of the digestive tract, cause liver damage and, as a result, affect the animal performance parameters. The main objective of this study was to verify the safety of the mealworm meal in the feed of laying hens from 17–42 weeks of age. Therefore, the feed mixtures were tested in terms of microbiological stability, fungal and mycotoxin content and selected parameters of hens’ intestinal morphology and physiology were monitored. Feed mixtures with proportions of insect products were microbially stable even after four months. Based on the results of this study, use of two to five percent of mealworm meal in hen′s diet may be used as a sustainable and safe protein feed.

Abstract

The main objective of this study was to verify the safety of mealworm meal in the feed of laying hens from 17 to 42 weeks of age. Therefore, the feed mixtures were tested in terms of microbiological stability, fungal and mycotoxin content and selected parameters of hens’ intestinal morphology and physiology were monitored. The experiment was carried out with 30 Lohmann Brown Classic hens. Hens were divided by body mass into three equal groups with 10 replicates per treatment. The two experimental groups received feed mixtures containing 2% and 5% yellow mealworm (Tenebrio molitor L.) meal. The third group was a control group which had 0% of mealworm meal in the diet. Diets with 2% and 5% of mealworm meals did not affect the length of villi and microbiome of the caecum. The highest digesta viscosity from the ileum was found in the group with 5% mealworm, which may indicate a slower passage of the digesta through the digestive tract. Based on our results, it may be concluded that the proportion of mealworm meals does not deteriorate the quality of feeds. Mealworm meal does not negatively affect microbial stability in experimental feeds. Therefore, it can be recommended the two and (or) five percent of mealworm meal inclusion in hen’s diet.

Effect of dietary inclusion of yellow mealworm (Tenebrio molitor) larvae meal on productive performance, egg quality indices and blood parameters of laying hens

Abstract Context Increasing demand for animal products, and scarcity and cost of conventional feed ingredients, drive the search for alternative energy and protein sources for poultry feed. Insects provide opportunities as a sustainable, high-quality and low-cost component of poultry feed. Aims This study evaluated the effects of dietary inclusion of powdered Tenebrio molitor (yellow mealworm) larvae meal on productive performance, egg quality characteristics and blood parameters of laying hens. Methods In total, 126 Bovans White laying hens, 63 weeks of age, were allocated to three dietary groups, each with seven replicate cages of six birds per cage. Treatments were: a basal diet, and two experimental diets comprising the basal diet plus T. molitor larvae meal at 2.5% or 5% inclusion rate. The duration of the study was 8 weeks. Key results Egg production, egg mass and feed conversion ratio were all improved (P &lt; 0.05) by inclusion of T. molitor meal in the diet. The lower rate of inclusion was more effective with respect to egg production and feed conversion ratio. Inclusion of larvae meal did not influence (P &gt; 0.05) feed intake, egg weight or bodyweight gain. Furthermore, egg quality characteristics and blood parameters were not influenced (P &gt; 0.05) by dietary treatment. Conclusions The study showed that inclusion of T. molitor larvae meal in the diet of laying hens could improve productive performance, especially at the 2.5% level. Implications Powdered meal of T. molitor larvae is an appropriate, unconventional feed ingredient for laying hens, and may have a role in improving socioeconomic and environmental outcomes, aligning with the United Nations’ sustainable development goals.

The use of organic concentrate in feeding quail

The article presents the results of the effect of partial replacement of mixed feeds with organic concentrate based on dry bird droppings (DBD) on the preservation of quail, quantitative and qualitative rates of egg productivity. For the laboratory experiment, 5 experimental groups of Manchurian quail were formed by the analogous pair comparison method. The quail of the control group consumed all-in-one feed (AF), for the quail of the experimental groups (I, II, III, and IV) part of the AF – 10, 15, 20 and 25 % by weight – was replaced with organic concentrate. Results of studies reveal that the introduction of 10 % of organic concentrate into the AF contributed to improved feed intake and livestock safety, increased egg productivity and reduced feed consumption per unit of output. With respect to the indicators of biological usefulness, toxicological and sanitary-epidemiological safety, quail eggs treated with the organic concentrate met the requirements of GOST and TR TS 021/2011 “On food safety”.