Feed endoxylanase type and dose affect arabinoxylan hydrolysis and fermentation in ageing broilers

Abstract

Despite the general use of endoxylanases in poultry feed to improve broiler performance, the abundance of different endoxylanase products and the variable response to their application in the field prevent a clear understanding of endoxylanase functionality in vivo. To gain insight into this functionality, we investigated the impact of endoxylanase type (Belfeed from Bacillus subtilis versus Econase XT from Nonomuraea flexuosa ) and dose (10, 100, 1,000 mg/kg) in combination with broiler age on arabinoxylan (AX) hydrolysis and fermentation in broilers (Ross 308) fed a wheat-soy based diet. In a digestibility trial and a performance trial, a total of 1,057 one-day-old chicks received the control diet or 1 of the 6 endoxylanase supplemented wheat-soy based diets with, respectively, 5 replicate cages and 8 replicate pens per dietary treatment per trial. The AX content and structure, the AX digestibility values and the short-chain fatty acids produced were analysed at the level of the ileum, caeca and excreta at d 11 and 36. Endoxylanase supplementation resulted in a more extensive solubilisation of wheat AX and a reduction in the intestinal viscosity compared to the control ( P < 0.05). A high endoxylanase dose was, however, required to obtain increased hydrolysis of the dietary AX along the gastrointestinal tract against the control ( P < 0.001). Depending on the type of endoxylanase, a pool of AX with distinct physicochemical properties was created. The B. subtilis endoxylanase created a large pool of soluble AX in the ileum, thereby increasing ileal viscosity compared to broilers fed an endoxylanase from N. flexuosa ( P < 0.001). The N. flexuosa endoxylanase mainly triggered caecal AX fermentation in young broilers, by delivering easily fermentable AX substrates with a low degree of polymerisation ( P = 0.03). The effects were particularly present in young broilers (d 11). From this study, it is clear that the type and dose of endoxylanase added to wheat-soy based diets determine the nature of AX substrates formed. These, in turn, affect the intestinal viscosity and the interplay between the dietary AX compounds and microbiota, hence dictating AX digestion at young broiler ages and performance outcomes towards slaughter age.

Ileal profile of non-starch polysaccharides and oligosaccharides in response to exogenous enzymes in broiler chickens offered wheat- or maize-based diets under subclinical necrotic enteritis challenge

“…On the other hand, supplemental XYN10 reduced total ileal insoluble NSP level, with no effect on soluble NSP or OS levels, suggesting there was likely comparatively less in situ production of AXOS with this enzyme treatment. The differences in substrate affinity between the 2 xylanases likely resulted in varying extents of polymeric AX degradation, as previously seen in many studies ( Choct et al., 2004 ; Morgan et al., 2017 ; Bautil et al., 2021 ). Thus, the disparity in ileal NSP degradation pattern between XYN10 and XYN11 implies that in situ enzymatic release of OS may be more closely associated with soluble NSP degradation than solubilisation of insoluble NSP.…”

Optimization of Compound Ratio of Exogenous Xylanase and Debranching Enzymes Supplemented in Corn-Based Broiler Diets Using In Vitro Simulated Gastrointestinal Digestion and Response Surface Methodology

“…Xylanase is thought to be a candidate to replace antibiotic growth promoters, and degrades AX in commercial corn or wheat basal diets for broilers [ 10 , 25 , 26 ]. Thus, an effective approach by xylanase supplementation could alleviate or even solve the antinutritional problems [ 1 , 2 ]. Differences in AX structure among cereals and their by-products are facilitated by many factors, such as cereal types, degree and pattern of substitution along the xylan backbone, phenol content, and cross linkages [ 5 ].…”

“…Compared with wheat and other cereals, AX in corn is particularly resistant to enzymatic disassembly. Although there have been numerous studies revealing the enzymatic hydrolysis behavior of supplemental endo-xylanase (EX), such effectiveness for both in vitro and in vivo settings were varied [ 1 , 2 , 3 , 4 ]. In addition, solitary EX has been proven to marginally degrade corn AX [ 5 ].…”

Isolation, Structural, Functional, and Bioactive Properties of Cereal Arabinoxylan─A Critical Review

“…However, because of the multiple cross-linking of WU-AX with other AX or cell wall components and the high viscosity of WE-AX, the digestion of other nutrients is hindered. To overcome these antinutritional effects, endoxylanase preparations are often added into animal feeds as additives. , In addition to the food use, AX has many applications in other industries. For example, it is used in sunscreen, adhesives, as a functional product added to pharmaceuticals, or as a delivery vehicle for drugs. ,, The application of AXs in these industries improves the utilization of grain byproducts, which is beneficial both economically and environmentally.…”

“…To overcome these antinutritional effects, endoxylanase preparations are often added into animal feeds as additives. 140,141 In addition to the food use, AX has many applications in other industries. For example, it is used in sunscreen, adhesives, as a functional product added to pharmaceuticals, or as a delivery vehicle for drugs.…”