Rumen degradability of dry matter and crude fibre of irradiated and sodium hydroxide treated straws.

Wheat straw (WS) and triticale straw (TS) were treated with 2- and 4%-NaOH and/or 300- and 600-kGy radiation doses (accelerated electrons) for improvement of the nutritional value of these feeds. Beside the chemical composition of straws, the nylon bag rumen disappearance of dry matter and crude fibre was estimated. NaOH did not influence the chemical composition of straws, while irradiation significantly reduced the level of crude fibre (CF), neutral detergent fibre (NDF) and acid detergent fibre (ADF) proportionally to the dose. The level of nitrogen free extractives (NFE) and alpha-linked glucose polymers pronouncedly increased in the radiated straws. NaOH treatment raised potential rumen degradability of DM and irradiation did so in the case of potential as well as effective degradability. It was not able to prove the summarized influence of both treatments on DM and CF rumen degradability of the straws. The dynamics of the rumen disappearance of DM was different in the straws.