EFFECTS OF OZONATION ON THE COMPOSITION AND ON THE INVITRO DIGESTIBILITY OF WHEAT STRAW

This work was designed to investigate the effect of a treatment by ozone on the composition and on the in vitro organic matter digestibility of wheat straw. Ground wheat straw (< 0,5 mm) was used in this study. Ozonation was performed on dry material and on material which was moistened to 500 % (0 - 5 g H2O / g of dry matter) prior to ozonation. Analyses were carried out on freeze-dried ozonated samples of wheat straw. The results obtained in this study showed that ozonation had no effect on the cellulose content and led to a decrease of the lignin content and to the formation of aqueous soluble substances such as soluble carbohydrates. The in vitro digestibility of wheat straw by rumen microorganisms was improved by treatment with ozone. Moreover, the results showed that the efficiency of ozone in enhancing the in vitro digestibility decreased when the moisture content of wheat straw increased.