[Determination of the nutritional value of lignocellulose materials].

The determination of the nutritive value of various secondary wood products was conducted by the method of the in-vitro digestibility of dry matter (Mellenberger et al., 1970) and by detergent analyses of fibre (Goering and Van Soest, 1970). Rumen contents for trials in vitro were obtained from adult wethers having a permanent rumen fistula and fed good meadow hay ad lib. The animals also had free access to water and mineral lick for sheep. Out of the 11 lignocellulose materials tested, digestibility in vitro higher than 60% (equivalent to the digestibility of high-quality meadow hay) was only found in three samples. These are: a) beech sawdust II treated with 0.1M sulphuric acid at the hydromodulus of 1:8, temperature 100 to 130 degrees C for two hours, and pressure of 0.25 MPa and then with 0.47M nitric acid at the hydromodulus of 1:13, temperature 100 degrees C for two hours and pressure of 0.25 MPa; b) beech sawdust III treated as beech sawdust II and then neutralized with ammonia to pH 8; c) aspen sawdust treated hydrobarothermically at a temperature of 280 degrees C and pressure of 7 MPa in saturated vapour medium (Canon system). The high digestibility of these samples was due to a low lignin content so that the polysaccharides (cellulose and hemicelluloses) of these secondary wood sources could be sufficiently utilized by rumen microflora.