The neutral detergent fiber (NDF using
heat-resistant a-amylase without sodium sulfite), acid detergent
fiber (ADF) and acid detergent lignin (ADL) were analyzed
according to Mertens (2002), AOAC (1990) (973.187),
and Van Soest et al. (1991), respectively, using the sequential
procedure and the filter bag system (Ankom Technology,
New York). The NDF and ADF fractions include residual
ash. N-free extract was calculated by difference. Hemicellulose
and cellulose were also estimated as NDF (ash free) ADF
(ash free) and ADF (ash free) – ADL (ash free), respectively