Evaluation of the metabolic effects of replacement of conventional protein sources by insect meal in growing broilers

近年来，富含蛋白质的昆虫粉作为一种替代蛋白质来源越来越受欢迎。虽然已经有几项研究表明，昆虫粉可以部分取代豆粕作为肉仔鸡饲料中的蛋白质来源，而不会影响动物的生产性能，但未来昆虫粉作为肉仔鸡饲料的潜在批准需要排除任何安全问题。然而，在肉鸡中全面描述昆虫粉对中间代谢影响的合适研究-这是确定与使用昆虫粉相关的潜在不良代谢影响的先决条件-缺乏。在此背景下，本项目旨在利用高通量筛选（组学）技术，综合评价黄粉虫粕对生长肉鸡中间代谢的影响。本项目的主要假设是，生长肉鸡饲粮中以TM虫粕替代豆粕会产生特定的代谢效应，具有科学意义，但不会对肉鸡的代谢产生不利影响。为了验证这一假设，将对日龄雄性Cobb 500肉鸡进行为期5周的饲养试验，这些肉鸡饲喂营养充足的等氮等能饲料，其中豆粕几乎全部或部分被TM幼虫的虫粕取代。为了确定TM粉对肉仔鸡代谢的影响，我们将采用转录组学、脂质组学和/或代谢组学对肉仔鸡血浆和两个高代谢活性组织（肝脏和胸肌）进行分析。此外，由于肠道微生物群对动物代谢的强烈影响，将利用肉鸡盲肠食糜进行微生物群组成分析，采用高通量16S rRNA基因扩增子测序。为了验证和详细描述筛选技术鉴定的TM粉的代谢作用，将根据鉴定的作用使用不同的分析技术，如qPCR、免疫印迹、（免疫）组织学、酶活性测定、色谱技术和/或ELISA。排除与在肉鸡生产中使用昆虫粉相关的任何安全问题（例如不利影响）对于确保食品安全尤其重要，因此对确保动物和消费者的健康具有重要意义。除了确保肉鸡生产中昆虫粉的安全性外，该项目的高度相关性还源于对可持续生产的蛋白质来源的日益增长的需求，以满足全球动物生产的增长。

Protein-rich insect meal has recently become attractive as an alternative protein source. While several studies already demonstrated that insect meal can partially replace soybean meal as protein source in feeding rations for broilers without impairing animal´s performance, the potential approval of insect meal as feed for broilers in the future requires that any safety concerns can be excluded. However, suitable studies in broilers which comprehensively describe the impact of insect meal on intermediary metabolism – a prerequisite to identify potential adverse metabolic effects associated with the use of insect meal – are lacking. Against this background the project aims to comprehensively evaluate the effects of insect meal from Tenebrio molitor (TM) on the intermediary metabolism of growing broilers using high-throughput screening (omics) technologies. The main hypothesis of this project is that replacement of soybean meal by insect meal from TM in the feeding ration for growing broilers induces specific metabolic effects, which are of scientific interest but are not detrimental to broilers´ metabolism. To test this hypothesis, a 5-week feeding trial with day-old male Cobb 500 broilers receiving nutrient-adequate isonitrogenous and isoenergetic feeding rations, in which soybean meal is replaced either almost completely or partially with insect meal from TM larvae, will be carried out. In order to identify TM meal-induced changes in the metabolism of broilers, blood plasma and two highly metabolically active tissues in broilers (liver and breast muscle) will be analyzed by transcriptomics, lipidomics and/or metabolomics. In addition, due to the strong impact of the gut microbiota on animals´ metabolism, the cecal digesta of the broilers will be used for analysis of microbiota composition using high-throughput 16S rRNA gene amplicon sequencing. To validate and detailly describe the metabolic effects of TM meal identified by the screening technologies, different analytical techniques such as qPCR, immunoblotting, (immuno)histology, enzyme activity assays, chromatographic techniques and/or ELISA will be used depending on the identified effects. The exclusion of any safety issues (e.g. adverse effects) associated with the use of insect meal in broiler production is of particular importance with regard to ensuring food safety and thus of great relevance for assuring animals´ and consumers´ health. Apart from ensuring the safety of insect meal in broiler production, the high relevance of this project arises from the increasing need to provide sustainably produced protein sources for the global increase in animal production.