Improving the nutritive value of wheat straw by applying the combined chemical-oxidation treatment in vitro for the use in ruminant nutrition

In this research, an ozone gas-based oxidation technique for enhancement of delignification along with urea-based chemical treatment as a nitrogen source was used to improve the nutritional value of wheat straw. The experiments were performed with four treatments and three replications in a completely randomized design. Experimental treatments of wheat straw were 1. Untreated sample, 2. Separate treatment with urea (3% w/w, 24 h), 3. Separate treatment with ozone (3 g/h, 45 min), and 4. Combined treatment of ozone (3 g/h, 45 min) with urea (3% w/w, 24 h). The results showed that ozonized treatments had a significant improvement (P<0.01) in the nutritional value of wheat straw compared to the untreated and urea-treated samples. Also, According to the results, the combined ozone-urea treatment increased the nutritional value of wheat straw more than urea and ozone treatment alone. The combined ozone-urea treatment caused a reduction of 18.28%, 7.97%, and 50% in NDF, ADF, and ADL, respectively. Also, improving the nutritional value was observed by increasing 333.3%, 22.5%, 23.67%, and 35.34% in CP, bonded organic-N, TDN, and RFV, respectively, and improvement of gas production parameters were obtained by increasing 100.21%, 63.76%, 34.93%, and 46.43% for GP24, ME, IVOMD24, and SCFA, respectively, as compared to control sample. Overall, from the results of this study, it can be concluded that combined ozone-urea treatment is comparable to traditional and existing novel treatment methods, which due to its ability to perform at ambient temperature, atmospheric pressure, and short-time treatment, can be used as a suitable alternative in agricultural straw treatments.