Effect of Ammoniationand Physical Treatmentof Wheat Straw

This experiment was conducted to evaluate effects of ammoniation (urea treated (T) and untreated (U)) and physical treatment (chopped (Ch) and unchopped (UCh)) of wheat straw on feed intake, digestibility, weight gain and carcass characteristics. Treatments were: urea treated and chopped (T-Ch), urea treated and unchopped (T-UCh), urea untreated and chopped (U-Ch) and untreated and unchopped (U-UCh) wheat straw. Urea treatment increased straw crude protein (CP) from 3.94 to 6.87% and decreased contents of neutral detergent fiber (NDF) from 84.61 to 78.21%. There was ammoniation by physical treatment interaction for the total DM and CP intakes. DM intake of T-Ch (460 g/d) > T-UCh (444 g/d) > U-Ch (443 g/d) > U-UCh (436 g/d) and that of CP intake was T-Ch > T-UCh > U-Ch > U-UCh with values of 81, 76, 69 and 68 g/d, respectively. The results of this study highlighted thepositive effect of ammoniation and physical treatment of wheat straw on intake, digestibility and animal performance, with possible additive effect of the two treatments when used in conjunction. However, the magnitude of effect on measured parameters appeared to be greater for ammoniation than physical treatment.