Comparison between two analytical methods for determining lignin concentration of some grass forages

Abstract

This work was carried out aiming to compare lignin concentration of some grass forages through two analytical methods (acid detergent lignin - ADL and permanganate lignin - PerL) as well to verify a possible relationship of lignin concentration with fiber digestion of the following grass hays: andropogon (Andropogon gayanus); oats (Avena sativa); a good quality and another of poor quality coast-cross (Cynodon dactylon). Acid detergent and permanganate lignin values were different (p £ 0.05) among the hays, however PerL concentrations were consistently lower than ADL values. There were differences (p £ 0.05) among the digestibility of neutral and acid detergent fiber fractions, however a clear relationship between these values with lignin concentration could not be assessed. The data suggested that lignin concentration, taken individually, is not the only factor to explain a given value of digestibility.