Submitted to: American Society of Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: July 8, 2004
Publication Date: November 30, 2004
Citation: Turner, K.E., Cassida, K.A. 2004. Analysis of detergent fiber fractions in high-pectin and high-tannin forages. In Agron. Abstr. [CD-ROM]. Amer. Soc. Agron., Madison, WI. Technical Abstract: Broadleaf forages often contain substances such as pectin, tannin, and ash that interfere with acid detergent fiber (ADF) measurements. We evaluated the effect of conventional non-sequential (CON) and sequential (SEQ) neutral detergent fiber (NDF) and ADF analysis and correction for acid insoluble ash (AIA) on ADF, AIA, and hemicellulose concentrations of forage samples analyzed individually or in a batch processing system. Analysis sequences were: 1) ADF, 2) NDF-ADF, 3) ADF-AIA, and 4) NDF-ADF-AIA. Hemicellulose concentration was calculated as the difference between NDF and ADF values. Forages tested included alfalfa, red clover, birdsfoot trefoil, sericea lespedeza, turnip top and root, forage rape leaf and stem, chicory, oats, smooth bromegrass/legume hay, and orchardgrass/tall fescue hay. Correction for AIA reduced ADF estimates similarly for CON and SEQ methods but this reduction was relatively small. Compared to CON analysis, SEQ analysis reduced ADF estimates by as much as 80 g kg-1 in high pectin forages, did not affect ADF estimates in low-tannin forage, and increased ADF estimates as much as 62 g kg-1 for high-tannin forage. Hemicellulose estimates were affected proportionately to changes in ADF estimates. Selection of appropriate fiber analysis methods is highly dependent on the cell components of greatest specific interest to study objectives.