title: Exogenous dietary xylanase ameliorates viscosity-induced anti-nutritional effects in wheat-based diets for White Pekin ducks (Anas platyrinchos domesticus).
abstract: Nutrient utilisation and growth performance responses of White Pekin ducks (Anas platyrinchos domesticus) offered diets containing low- or high-viscosity wheat supplemented with xylanase were investigated in two studies. In Expt 1, six diets consisting of low-viscosity wheat or high-viscosity wheat supplemented with 0.0, 1.5 or 3.0 g xylanase (2590 units/g)/kg diet were used in a true metabolisable energy (TME) bioassay with eight 8-week-old ducks per diet group. In Expt 2, eight pens of ten 3-d-old ducks per pen for each of six wheat-based diets arranged in a 2 x 3 factorial of low-viscosity or high-viscosity wheat and 0.0, 1.5 or 3.0 g xylanase/kg were used in a 42 d growth study. High-viscosity wheat depressed (P<0.001) TME and xylanase supplementation improved (P<0.001) TME, more so for high-viscosity than low-viscosity wheat. Xylanase supplementation of the high-viscosity wheat-based diet improved (P<0.05) weight gain and gain:feed ratio by 13 and 12 % respectively. There was no weight gain or gain:feed ratio response to xylanase supplementation of the low-viscosity wheat-based diet. Xylanase supplementation reduced (P<0.001) the viscosity of duodenal and ileal digesta for high-viscosity but not low-viscosity wheat-based diets. Ileal digestibilities of nutrients and energy were higher (P<0.001) for low-viscosity than high-viscosity wheat-based diets; xylanase supplementation improved (P<0.05) energy, fat, N and starch digestibilities. Given that xylanase supplementation of high-viscosity wheat assuaged its anti-nutritional effect, it is surmised that digesta viscosity plays a role in anti-nutritional effects in wheat-based diets for ducks.
authors.affiliation: Department of Animal Sciences, Purdue University, West Lafayette, IN 47907, USA. ladeola@purdue.edu
authors.forename: Olayiwola
authors.initials: O
authors.lastname: Adeola
authors.forename: Michael R
authors.initials: MR
authors.lastname: Bedford
mesh_terms: D000821:Animal Feed; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D019587:Dietary Supplements; D004063:Digestion / Q000502:physiology; D004372:Ducks / Q000254:growth & development / Q000502:physiology*; D004386:Duodenum / Q000502:physiology; D043364:Endo-1,4-beta Xylanases / Q000008:administration & dosage / Q000494:pharmacology*; D004734:Energy Metabolism / Q000502:physiology; D005772:Gastrointestinal Transit; D007082:Ileum / Q000502:physiology; D008297:Male; D014908:Triticum; D014783:Viscosity; D015430:Weight Gain / Q000502:physiology
chemical_list: D043364:Endo-1,4-beta Xylanases