In Vitro Digestibility and Gas Production as Affected by Supplementation of Protein to Urea-Treated Wheat Straw

In vitro dry matter digestibility (IVDMD) and gas production (IVGP) were estimated using rumen liquor from 3 rumen fistulated adult maie cattle fed according to their requirments. Urea treated wheat straw (CP 7.45%) supplemented with 0, 3, 5, 7, 9, 11, 13 and 15% CP through groundnut cake was used as substrate. Corresponding values for IVDMD (P<0.01) were 51. 66, 53J5, 56.33, 55.59, 56.95, 57.87, 59.42 and 60.21%. IVGP (ml/0.5g substrate) in respective treatments on 481s of incubation was 51.5, 51.6, 51.6, 52.1, 53.7, 51.4, 57.4 end 59.3 (P<0.05). K values decreased from 0.1415 (T₁) to 0.1156 (T₈). Though K₂ values decreased significantly (P<0.01) with increase in protein level but no definite trend was observed. Coefficients of gas production (ml/h) indicated that increasing levels of protein affected fermentation in first phase of 12 h only. Thus, IVDMD and IVGP increased with increase in protein level. IVGP and supplementary CP levels were having significant positive correlation with IVDMD and IVOMD. With increase in protein content In the substrate, ME values (MJ/kg DM) tended to increase.