Prediction of Effective Dry Matter and Fiber Degradability of Tropical Roughages

Forages fed to ruminants in tropics (n=19) were analyzed for their detailed chemical composition and in sacco degradation kinetics to evaluate TDN content and DM and NDF degradability in buffaloes. The CP content among the forages varied from 4.4 (Heteropogon) to 20.42% (guar fodder with pod) while EE varied from 0.77 (wheat straw) to 2.98% (pearl millet). NDF and ADF contents ranged from 31.56 (guar with pod) to 77.92% (wheat straw) and from 28.45 (guar with pod) to 54.26% (buffel grass), respectively, where as, the lignin level ranged from 2.28 (oats) to 12% (buffel). The NDF bound CP ranged from 0.67 to 6.11% and ADF bound CP from 0.22 to 3.25%. The dry matter ‘a’ (quickly soluble fraction) ranged from 9.8 (sorghum stover) to 39.65% (fenugreek), whereas ‘b’ (slowly degradable fraction) ranged from 39.34 (pearl millet fodder) to 74.8% (crysopogon) whereas for NDF the ‘b’ fraction ranged from 33.39 (sorghum stover) to 85.47% (oats fodder). The effective degradability of DM (EDDM) and NDF (EDNDF) ranged from 48.95 (Heteropogon) to 71.83% (fenugreek) and 15.23 (sorghum stover) to 60.55% (guinea grass), respectively. Following linear regression equations were evolved to predict the effective degradability (ED) from chemical composition, EDDM= 81.75–0.46 NDF (R²= 0.63, P<0.01), EDDM= 83.0517–0.45NDF- 0.53 NDICP (R² = 0.64, P<0.05), EDDM= 79.91554–0.44 NDFn, EDNDF= 84.24–1.02ADF (R²= 0.55, P<0.05).