Impact of accessibility and chemical composition on cell wall polysaccharide degradability of maize and lucerne stems

摘要: Although lignification of forages is generally accepted as limiting cell wall degradability, prediction degradation from composition often difficult when are similar maturity. It has been proposed that rumen microbe accessibility to potentially degradable walls limited by the presence non-disrupted cells in forage particles with lignified middle lamella/primary acting barriers microbial access. We tested this hypothesis evaluating impact reducing particle size maize and lucerne stems level individual ball-milling, order eliminate a factor. While concentration were not influenced ball-milling compared grinding pass 1 mm screen cyclone-type mill, degradability total polysaccharides was dramatically increased. However, only those (cellulose xylan) which most abundant types secondary increased owing reduction. Degradability pectins, non-lignified tissues lucerne, did respond ball-milling. Contrary our expectations, ball-milled showed fewer correlations for than observed larger-particle-size treatment. Many components correlated polysaccharide cyclone-ground samples; however, results inconsistent among within forages. This observation does clarify role chemical structure agent absence barriers, but study provide support act access degradation.