Project description:Submerged cultivation using low-value agro-industrial side streams allows large-scale and efficient production of fungal mycelia, which has a high nutritional value. As the dietary properties of fungal mycelia in poultry are largely unknown, the present study aimed to investigate the effect of feeding a Pleurotus sapidus (PSA) mycelium as a feed supplement on growth performance, composition of the cecal microbiota and several physiological traits including gut integrity, nutrient digestibility, liver lipids, liver transcriptome and plasma metabolome in broilers. 72 male, 1-day-old Cobb 500 broilers were randomly assigned to three different groups and fed three different adequate diets containing either 0% (PSA-0), 2.5% (PSA-2.5) and 5% (PSA-5.0) P. sapidus mycelium in a three-phase feeding system for 35 days. Each group consisted of 6 cages (replicates) with 4 broilers/cage. Body weight gain, feed intake and feed:gain ratio and apparent ileal digestibility of crude protein, ether extract and amino acids were not different between groups. Metagenomic analysis of the cecal microbiota revealed no differences between groups, except that one α-diversity metric (Shannon index) and the abundance of two low-abundance bacterial taxa (Clostridia UCG 014, Eubacteriales) differed between groups (P < 0.05). Concentrations of total and individual short-chain fatty acids in the cecal digesta and concentrations of plasma lipopolysaccharide and mRNA levels of proinflammatory genes, tight-junction proteins, and mucins in the cecum mucosa did not differ between groups. None of the plasma metabolites analyzed using targeted-metabolomics differed across the groups. Hepatic transcript profiling revealed a total of 144 transcripts to be differentially expressed between group PSA-5.0 and group PSA-0 but none of these genes was regulated greater 2-fold. Considering either the lack of effects or the very weak effects of feeding the P. sapidus mycelium in the broilers it can be concluded that inclusion of a sustainably produced fungal mycelium in broiler diets at the expense of other feed components has no negative consequences on broilers´ performance and metabolism.
Project description:Despite the need to enhance feed production for monogastric farm animals, this challenge is complicated by the fact that natural resources are becoming increasingly limited and climate protection goals have to be considered. Thus, there is a need for alternative feed sources, which are produced in a resource-efficient and sustainable manner. Valorization of low-value agricultural sidestreams by edible fungi, such as Pleurotus sapidus (PSA), has been proposed as a strategy to utilize such sidestreams as a sustainable source of feed for monogastric farm animals, because P. spp. are capable of degrading a wide array of fiber-rich substrates. In a recent study, we have demonstrated that feeding a biotechnologically produced PSA mycelium to broilers does not affect growth performance and nutrient digestibility and causes only weak effects on the cecal microbiota community, the liver transcriptome and the plasma metabolome of broilers. In order to clarify if the effect of the mycelium differs from that of the fruiting bodies, the present study investigated the effect of PSA fruiting bodies on the performance, the gut microbiome and the transcriptome and the lipid metabolism in the liver of broilers.