Nutritional value determination of beam irradiated barley straw

In this study, barley straw was irradiated with doses of 100, 200 and 300 KGy to evaluate the effects of electron beam on the chemical composition, ruminal degradability parameters and ruminal-postruminal digestibility of its dry matter (DM). Initially, using nylon bag technique, an amount of 5 g of grounded samples (with 6 replicates) was incubated for 0, 2, 4, 8, 16, 24, 48 and 72 h in the rumen of two fistulated Holstein heifers and then parameters of DM ruminal degradability were estimated. Then ruminal digestibility and post ruminal digestibility of DM were determined by incubating of feed samples in rumen for 16 h and in Daisy digester apparatus, respectively. Statistical analysis of the data was performed using SAS statistical software. The results indicated that acid detergent fiber (ADF) in irradiated samples was numerically reduced, while NDF reduction of irradiated samples was statistically significant (P<0.05). Effective degradability of DM increased significantly (P<0.05) by irradiation at 200 KGy. Post-ruminal and total tract digestibility of DM increased significantly (P<0.05). The results of this experiment showed that electron beam irradiation had an effective role in improving the nutritive value and digestibility of barley straw, but regarding the absence of a dose related effect, the dose of 200 kGy is recommended.