Effect of Insect Live Larvae as Environmental Enrichment on Poultry Gut Health: Gut Mucin Composition, Microbiota and Local Immune Response Evaluation

Abstract

The aim of this study was to evaluate the effect of Hermetia illucens (HI) and Tenebrio molitor (TM) live larvae as environmental enrichment on the mucin composition, local immune response and microbiota of broilers. A total of 180 four-day-old male broiler chickens (Ross 308) were randomly allotted to three dietary treatments (six replicates/treatment; ten animals/replicate): (i) control (C); (ii) C+HI; (iii) C+TM. Live larvae were distributed based on 5% of the expected daily feed intake. At slaughter (39 days of age), samples of duodenum, jejunum and ileum (twelve animals/diet) were submitted to mucin histochemical evaluation. Expression of MUC-2 and cytokines was evaluated by rt-qPCR in jejunum. Mucin staining intensity was not influenced by diet (p > 0.05); however, this varied depending on the intestinal segment (p < 0.001). No significant differences were recorded for IL-4, IL-6 TNF-α, MUC-2 and INF-γ gene expression in jejunum, while IL-2 was lower in the TM group compared to HI and C (p = 0.044). Caecal microbiota showed higher abundance of Clostridium, Saccharibacteria and Victivallaceae in the HI group, while Collinsella was higher in the TM group. The results suggested that live insect larvae did not impair mucin composition or local immune response, and can slightly improve caecal microbiota by enhancing a minor fraction of short chain fatty acid-producing taxa.

The bone-degrading enzyme machinery: From multi-component understanding to the treatment of residues from the meat industry

“…It is to highlight that there are a small number of microorganisms that can secrete both acids and collagenases, and that this study suggest that these microorganisms are enriched in bone-associated microbiomes where sulfur, and also nitrogen, polysaccharides and polypeptides biogeochemistry co-exists. Finally, biochemical knowledge for members of Victivallaceae and Kiritimatiellae , from which few cultured representatives are available [53] , [54] , is limited; in this study, their capacity to presumptively degrade collagen, and α-mannose, α-fucose and β-galactose residues is suggested. Opposite, this study reinforces the carbohydrate-based fermentative lifestyle of members of Anaerolineae , Clostridiaceae, Lentisphaeria , Paenibacillaceae, Planctomycetota, and Verrucomicrobiae , which being enriched in key genes catalyzing the hydrolysis of multiple of polysaccharides are also common inhabitants of the gut.…”

Nutrigenomics in Animal Feeding: Digital Gene Expression Analysis in Poultry Fed Tenebrio molitor Larvae Meal

“…Insect production requires less energy, less land utilization, and consequently, exerts a lower environmental impact [1][2][3][4]. Several studies highlighted the opportunity to use insects, containing a large amount of high-quality protein, as a standard ingredient in animal feeds [5][6][7][8][9][10]. Furthermore, insect meal as a protein source represents a unique opportunity for animal nutrition due to its low competitiveness with human nutrition [11].…”

“…Nevertheless, the chitin content can negatively affect the digestibility of proteins and reduce the overall digestion [15,16]. Therefore, high levels of TM meal inclusion (10-15%) in male broiler chicken diets seems to improve feed intake, but negatively affect feed efficiency, intestinal morphology, and mucin dynamics, with a significant reduction in villus height, villus height to crypt depth ratio, and villi mucin staining intensity [5,8,12,14,15].…”

Eggs or meat? Environmental impact and efficiency assessment of chicken protein production with potential of Hermetia illucens use in feed

“…When feeding insect meal to laying hens, there were minor negative effects, such as a reduction in egg size or an increase in liver size (Brah et al, 2017;Mwaniki et al, 2020). Also, whole BSFL are applicable as poultry feed both in live and dried form (Balolong et al, 2020;Colombino et al, 2021;Irawan et al, 2019) and can additionally improve bird´s welfare (Bellezza Oddon et al, 2021;Ipema et al, 2020;Star et al, 2020).…”