Effects of cereal grain source and supplemental xylanase concentrations on broiler growth performance and cecal volatile fatty acid concentrations from 1 to 40 d of age

Authors: MCCAFFERTY, KLINT - Auburn University; BEDFORD, MIKE - Ab Vista; Kerr, Brian; DOZIER, WILLIAM - Auburn University

Submitted to: Journal of Applied Poultry Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/16/2019
Publication Date: 7/1/2019
Citation: McCafferty, K.W., Bedford, M.R, Kerr, B.J., Dozier III, W.A. 2019. Effects of cereal grain source and supplemental xylanase concentrations on broiler growth performance and cecal volatile fatty acid concentrations from 1 to 40 d of age. Journal of Applied Poultry Research. 98(7):2866-2879. https://doi.org/10.3382/ps/pez032.
DOI: https://doi.org/10.3382/ps/pez032

Interpretive Summary: Enzyme supplementation has become a key part of diet formulation in broilers due to their ability to reduce the effects of non-starch polysaccharides in cereal grains. One of these enzymes, xylanase, has been shown to be effective in diets formulated with rye, wheat, or triticale. The current study was conducted to examine the effects various concentrations of supplemental xylanase in corn- or wheat-based diet on broiler growth performance and cecal volatile fatty acid concentrations during a 6-week production period. Data from this experiment indicated that supplemental xylanase did not affect cecal volatile fatty acid concentrations, and neither cereal grain source nor supplemental xylanase affected cumulative broiler growth performance. This information is important for nutritionists at universities, feed companies, and broiler production facilities for determining the value of a xylanase enzyme on improving the digestion of non-starch polysaccharides in diet feed formulations fed to growing broilers and on how the cereal grain source affects bird performance.

Technical Abstract: An experiment was conducted to evaluate the effects of feeding diets varying in cereal grain source and supplemental xylanase concentrations on growth performance and cecal volatile fatty acid (VFA) concentrations of Ross × Ross 708 male broilers from 1 to 40 d of age. One thousand five hundred thirty-six day-old chicks were randomly distributed into 64 floor pens (24 chicks/pen; 0.08 m2/bird) and fed 1 of 8 dietary treatments (TRT) with 8 replicates per TRT. Experimental TRT were of either corn- (TRT 1 to 4) or wheat-based (TRT 5 to 8) origins. The 4 dietary TRT for each cereal grain source consisted of a positive control (PC) reference diet and 3 reduced nitrogen corrected apparent metabolizable energy (AMEn) diets (AMEn reduced 66 kcal/kg below PC) with supplemental xylanase at either 0 (negative control), 12,000, or 24,000 BXU/kg. Birds and feed were weighed at 1, 14, 26, and 40 d of age to determine BW gain (BWG), feed intake (FI), and feed conversion ratio (FCR). At 26 and 40 d of age, cecal contents were collected and pooled per pen (7 birds/pen; 5 replicate pens/TRT) for VFA concentrations. No TRT differences (P > 0.05) in cumulative growth performance were observed. Likewise, no TRT differences (P > 0.05) in acetic or total VFA concentrations were observed at 26 or 40 d of age. However, cereal grain source (P < 0.05) influenced propionic, isobutyric, butyric, and isovaleric concentrations at 26 and 40 d of age with birds receiving the corn-based diets having higher (P < 0.05) cecal propionic, isobutyric, and isovaleric concentrations, and lower (P < 0.05) butyric acid concentrations than those fed the wheat-based diets. These results indicate that dietary cereal grain source may influence individual cecal VFA concentrations. However, supplemental xylanase did not affect broiler growth performance or cecal VFA concentrations. Therefore, future research evaluating factors limiting xylanase responses on broiler growth performance and cecal VFA production is warranted.