Influence of Temperature, Relative Humidity and Protein Content on the Growth and Development of Larvae of the Lesser Mealworm, Alphitobius diaperinus (Panzer)

The human population is rapidly growing, subsequently leading to an increase in food and protein demand. Therefore, alternative protein sources have to be evaluated as food and feed. Among the most promising alternative protein sources with significant advantages are insects. Nevertheless, insect rearing conditions have to be optimized prior to insect mass production. In the present study, using laboratory bioassays, we evaluated the effect of several biotic and abiotic factors on the development of the larvae of the lesser mealworm, Alphitobius diaperinus (Panzer). In the first series of bioassays, we investigated A. diaperinus larval growth at three temperatures (25, 30 and 32 °C) and two relative humidity (r.h.) levels (55 and 75%). Furthermore, in the second series of bioassays, the larval growth was assessed on wheat bran-based substrates with different percentages of yeast, i.e., 0%, 10%, 17.5%, 25%, 32.5% and 40%. According to our results, the temperature was shown to be highly important for larval development, with A. diaperinus larvae performing better at the higher temperatures tested, i.e., 30 and 32 °C. In contrast, relative humidity did not have a significant effect on A. diaperinus growth, at least for the relative humidity levels tested. Finally, the increase in the percentage of yeast in the diet increased larval growth, development and survival. Our study aims to highlight the significance of several biotic and abiotic factors for the rearing of A. diaperinus larvae, providing parameters that can be further utilized in mass rearing protocols of this species.

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Identification and Evaluation of Factors Affecting Nectar Volume and Concentrations of Croton Macrostachyus Hochst.ex Delile

10.21203/rs.3.rs-952506/v1 ◽

2021 ◽

Author(s):

Kasim Roba Jilo ◽

Getachew Sime

Keyword(s):

Relative Humidity ◽

Sucrose Concentration ◽

Abiotic Factors ◽

Time Of Day ◽

Factors Affecting ◽

Nectar Volume ◽

Biotic And Abiotic Factors ◽

Honey Production ◽

Nectar Concentration ◽

Croton Macrostachyus

Abstract Background: Secretion of nectar is highly influenced by many factors and the objective of the study was also to evaluate factors affecting concentrations of nectar of Croton macrostachyus Hochst.ex Delile. Age of plants highly affect nectar concentration and volume. Honey quality and its medicinal values depends on plants species variety and their sucrose concentration quality and quantity which is governed by many biotic and abiotic factors as well micro climate of the area. Wholesale of nectar and concentration of tend to show more differences in time of day for species study undertaken.Results: As results publicized that nectar concentration and volume of youngest age was not more affected by temperature and relative humidity like that of medium and oldest ages. Temperature and age have significant effect on volume (p = 0.0001) and their interactions is also significant (p = 0.01145). Temperature has significant effects on nectar concentration (p = 0.000). Interaction of relative humidity, time, and layers has significant effects on nectar concentration (p = 0.0024012). The oldest plants had the highest concentration of 10.1 w/w mornings and afternoon 36.5 w/w at 4:00 PM for whereas medium plants had nectar concentration of 5.7 w/w morning and afternoon 16.7 w/w and the smaller or younger plants had nectar concentration of 2.7 w/w mornings and afternoon 9.1 w/w and this shows age significantly affect nectar concentration and volume.Conclusions:Concentration and volume were affected by many biotic and abiotic factors. I conclude imminent fever intensification could harm nectar production since for croton also no nectar could be collected at 30 C⁰ and no nectar recreation was observed after this peak temperature this indicates environmental change can increase the temperature which will have negative influences on honey production in the future unless we combat against climate change which will affect honey production and productivity for the country and we will lose honey and its medicinal values also.

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Effects of two diets on adults’ survival and productivity in mass-rearing of Tenebrio molitor (Coleoptera: Tenebrionidae)

Journal of Insects as Food and Feed ◽

10.3920/jiff2020.0129 ◽

2021 ◽

pp. 1-10

Author(s):

S. Naser El Deen ◽

F. Lamaj ◽

V. Verrastro ◽

L. Al Bitar ◽

F. Baldacchino

Keyword(s):

Wheat Bran ◽

Larval Growth ◽

Mass Rearing ◽

Tenebrio Molitor ◽

Nutritional Composition ◽

Alternative Protein ◽

Set Up ◽

Positive Effect ◽

By Products ◽

Coleoptera Tenebrionidae

Yellow mealworm is a grain infesting pest that is receiving attention nowadays as an alternative protein source for humans and animals. Its ability to convert low quality feed, like organic by-products, into high-quality food increases its production sustainability. The feeding diet is one of the most important factors in rearing Tenebrio molitor Linnaeus (Coleoptera: Tenebrionidae), which affects its growth, longevity and nutritional composition. Many by-products have been tested on larvae, but studies are scarce on adults. This work aimed to compare the effect of chicken feed diet (C) and wheat bran (B) by-product, as well as integrating yeast (CY and BY), on the adults’ reproduction and larval growth. Experiment was set up in a complete productive cycle of mass-rearing. The evaluation was done on the reproductive stage of the adults and the development of the larvae until harvesting (appearance of the first pupa). Results showed that the bran-based diets significantly improved the adults’ survival; after 50 days, mean of 110 and 146 adults survived on B and BY diets respectively compared to mean of 23 adults when reared on both chicken feed diets. Besides, wheat bran supplemented with yeast improved the total number of larvae (6,448.2 larvae) compared to bran diet (4,016.7 larvae). Whereas the two chicken feed-based diets had significant positive effect on the average larval weight; the maximum weight reached was 116.3 mg and 145.8 mg for larvae read on C and CY diets respectively compared to 47.8 mg and 57.3 mg on B and BY diets. Nevertheless, in 50 days of reproduction, the total larval biomass was highest on bran supplemented with yeast (283.1 g). In conclusion, the increase of sustainability and efficiency in mass-rearing of mealworms is possible by using appropriate diets on respective stages; bran-based diets for reproduction and chicken feed-based diets for larval growth.

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Rearing Tenebrio molitor and Alphitobius diaperinus Larvae on Seed Cleaning Process Byproducts

Insects ◽

10.3390/insects12040293 ◽

2021 ◽

Vol 12 (4) ◽

pp. 293

Author(s):

Christos I. Rumbos ◽

Dimitrios Bliamplias ◽

Marina Gourgouta ◽

Vasilios Michail ◽

Christos G. Athanassiou

Keyword(s):

Larval Growth ◽

Tenebrio Molitor ◽

Feed Utilization ◽

Economic Feasibility ◽

Cleaning Process ◽

Farming Practices ◽

Legume Seed ◽

Growth And Survival ◽

Alphitobius Diaperinus ◽

Lesser Mealworm

The exploitation of agricultural byproducts and organic side-streams as insect feeding substrates is advantageous for insect farming both from an economic and a sustainability perspective. In this context, in the present study we evaluated the suitability of ten byproducts of the cereal and legume seed cleaning process for the rearing of larvae of the yellow mealworm, Tenebrio molitor, and the lesser mealworm, Alphitobius diaperinus. Byproducts were offered singly to 20 T. molitor and 50 A. diaperinus larvae with provision of carrots as moisture source. After four weeks of undisturbed development, larval weight and survival was evaluated biweekly until pupation. Feed utilization and economic feasibility parameters were determined for each byproduct at the end of the bioassays. Our results show the suitability of several of the byproducts tested for the rearing of T. molitor and A. diaperinus larvae. The best results though among the byproducts tested in terms of larval growth and survival, development time and feed utilization were obtained with larvae fed with lupin and triticale byproducts, which efficiently supported complete larval development. The results of our study aim to boost the integration of circular economy strategies with insect farming practices.

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Agri-Food Side-Stream Inclusions in the Diet of Alphitobius diaperinus Part 1: Impact on Larvae Growth Performance Parameters

Insects ◽

10.3390/insects11020079 ◽

2020 ◽

Vol 11 (2) ◽

pp. 79 ◽

Cited By ~ 2

Author(s):

Natasja Gianotten ◽

Lise Soetemans ◽

Leen Bastiaens

Keyword(s):

Large Scale ◽

Larval Growth ◽

Rapeseed Meal ◽

Larval Performance ◽

Alphitobius Diaperinus ◽

Side Stream ◽

Wheat Middlings ◽

Economical Aspect ◽

Lesser Mealworm ◽

The Impact

Insects are attracting increased attention in western countries as a protein source for feed and food industries. Currently, insect farmers use high-quality (cereal-based) diets. Part of the ingredients in these diets can also be used directly in food applications. To avoid competition and improve the sustainable and economical aspect of insect rearing, a search for alternative insect diets is ongoing. Side-streams from the agri-food sector offer potential. The lesser mealworm (Alphitobius diaperinus) is an insect that is commercially reared on large scale for food application. The current paper reports on six agri-food side-streams that were included in the diet of the lesser mealworm. The impact of 29 diets (single side-streams or mixtures) on the larvae growth was evaluated by monitoring the larval yield, efficiency of conversion of ingested feed, and larval weight. The larvae were able to grow on all diets, but differences in growth were observed. Two side-streams, wheat middlings and rapeseed meal, were proven to support good larval performance when used as a single ingredient. A combination of these two with brewery grains as moisture source provided (1) the best larval growth and (2) the most economically profitable diet. In conclusion, this study illustrates successful rearing of the lesser mealworm on side-stream-based diets.

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