Carbohydrate and protein fractions, nutritive value and energetic efficiency in different sorghum accessions

Abstract

Under sorghum breeding programme, 19 accessions (IC-355466 to IC-355484) along with 2 national checks (CSV 15 and SSG59-3) grown under identical agronomic conditions and harvested at 50 % flowering stage, were screened for their crude protein (CP), fiber contents, carbohydrate fractions, protein fractions, methane production and palatability attributes. Accessions mean CP and ether extract contents were 7.68 and 1.65%, respectively. Accessions NDF, ADF, cellulose and lignin ranged between 62.94-75.14, 38.31-50.45, 29.09-34.63 and 5.51-12.42%, respectively. Sorghum accessions mean value for moderately degradable protein fraction (PB2) was 32.32% of CP and lignin bound protein fraction (PC ) was 1.21% of CP. Slowly degradable cell wall carbohydrate fraction (CB2) and intermediately degradable carbohydrate fraction (CB1) contents were 52.5 and 0.67% of CHO, respectively in the accessions. Sorghum accessions differed (P<0.05) in methane production and ranged between 90.4 to 99.13 g/kg DDM. Intake, IVDMD and relative feed values of accessions differed significantly (P<0.05). Accessions energetic efficiency mean values for lactation (NEL ), maintenance (NEM ) and gain (NEG ) were 1.09, 1.14 and 0.421 Kcal/g, respectively. Sorghum accessions IC-355475, IC-355479 and IC-355- 483 were rich in protein, low to medium in fiber, NDIP and SC, high in TDN, DMI, RFV and low in methane production.