Evaluation of Dual-purpose Sorghum Hybrids for Nutritional Quality, Energetic Efficiency and Methane Emission

Present study evaluated 25 dual-purpose sorghum hybrids for their nutrient contents, in sacco DM digestibility, nutritive value and methane emission potential. The CP, OM, EE, NDF, ADF, cellulose and lignin contents of the hybrids differed significantly (P < 0.05) and mean values were 99.0, 924, 15.0, 604, 334, 264 and 42.5 g kg(-1) DM, respectively. Carbohydrate content and its fraction varied across the hybrids significantly (P < 0.05). The hybrids differed (P < 0.05) in terms of DM intake (DMI), leaf to stem ratio and digestible DM (DDM) with the values ranging between 1.78 to 2.32%, 11:89 to 26:74 and 59.4 to 67.2%, respectively. In sacco degradability of DM, OM, CP, NDF, ADF and cellulose varied (P < 0.05) amongst the hybrids. Relative feed value (RFV) and TDN varied (P < 0.05) from 81.9 and 55.7 for the hybrid 716A x NTI-2 to 120 and 67.9% for 685A x ICSR89 hybrid. The hybrids differed (P<0.05) in their DE and ME contents with the mean values being 12.2 and 10.0 kJ g(-1) DM, respectively. Net energy efficiency for maintenance (NEm), lactation (NEl) and growth (NEg) of tested hybrids differed and ranged between 5.52 to 7.11, 5.19 to 6.53 and 2.51 to 4.10 kJ g(-1) DM, respectively. The methane production varied (P < 0.05) significantly and ranged from 45.8 to 82.1 g kg(-1) DDM. Male sterile lines viz. 686A, 685A and 716A resulted in higher values for CP, nutrient degradability, DMI and RFV in their respective hybrids. Results indicated that hybrids 686A x IS 697, 685A x ICSR 89 and 685A x GP 65072 are nutritionally superior with low to moderate methane production potential.