The effect of different wheat varieties and exogenous xylanase on bird performance and utilization of energy and nutrients

The aims of the present study were to first, determine the xylan fractions of 10 different wheat cultivar samples and their response to treatment by the same commercial xylanase enzyme preparation. Second, use information obtained to select 5 of the wheats for use within a feeding experiment to determine whether the rate of xylan release can be used to predict the feed-ing value of the wheats when diets have been supple-mented with xylanase. Treatment of 10 different wheat varieties by the same enzyme resulted in varying levels of hydrolysis. Soluble xylan content ranged from 7.85 to 14.40 and 3.20 to 5.13 (mg/g) when treated with and without xylanase, respec-tively. Oligosaccharide content ranged from 0.34 to 1.58 and 0.05 to 0.54 (mg/g) when treated with and without xylanase, respectively. Five of the 10 wheats were then selected based on the determined xylan fractions to use within a feeding experiment. A total of 360 male Ross 308 broilers were randomly allocated to 60 raised floor pens. A soybean meal (SBM) balancer feed was formu-lated to contain 12.07 MJ/kg apparent metabolizable energy (AME) and 392.9 g/kg crude protein (CP). Five diets were prepared by mixing 630 g/kg of each of the 5 experimental wheats with 370 g/kg of the balancer. Each diet was split into 2, one of which was supple-mented with 100 g/MT of Econase XT (223,000 BXU/ g), resulting in a total of 10 diets. The birds were fed the diets from 0 to 28 d of age. Wheat cultivar had an effect (P = 0.044) on feed intake (FI), while the addition of xylanase increased (P < 0.05) weight gain (WG) and improved feed conversion ratio (FCR). Various interac-tions were observed (P < 0.05) between wheat cultivars and xylanase for AME and nutrient utilization. This study suggests that wheats treated with the same xyla-nase, differ in their susceptibility to release soluble xylan and oligosaccharides, which may partially explain the varying performance and nutrient digestibility responses noted in the literature.

Automated summary

The present study aimed to determine the xylan fractions of 10 wheat cultivars and their response to treatment by the same commercial xylanase enzyme preparation. Information obtained was used to select 5 wheats for a feeding experiment to predict the feeding value based on the rate of xylan release. Treatment with the same enzyme resulted in varying levels of hydrolysis, and the addition of xylanase improved weight gain and feed conversion ratio.