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

This work was carried out aiming to compare lignin concentration of some gr ass forages through two analytical methods (acid detergent lignin - ADL and permanganate lignin - Pert) as well to verify a possible relationship of l ignin concentration with fiber digestion of the following grass hays: andro pogon (Andropogon gayanus); oats (Avena saliva); a good quality and another of poor quality coast-cross (Cynodon dactylon). Acid detergent and permang anate lignin values were different (p less than or equal to 0.05) among the hays, however Pert concentrations were consistently lower than ADL values. There were differences (p less than or equal to 0.05) among the digestibil ity of neutral and acid detergent fiber fractions, however a clear relation ship between these values with lignin concentration could not be assessed. The data suggested that lignin concentration, taken individually, is not th e only factor to explain a given value of digestibility.