In the present study an estimation of livestock enteric CH4 emission has been made from feeding systems (diets) for different animal functions (maintenance, production and growth) prevailing in different agroecological regions (AERs) of India using livestock population 2003. Estimations comprised of dietary intake, digestibility and CH4 emission factors for ruminant species of different age groups determined from feeding systems/diets. Methane production (ml g–1) from production diets in animal species tended to be more than growth and maintenance diets.

Dry roughages, viz. wheat straw (WS), rice straw (RS), barley straw (BS), oat straw (OS), gram straw (GS), lentil straw (LS), sorghum stover (SST), pearl millet stover (PMST), maize stover (MST) and dry mixed grass (DG) fed to livestock were characterized for carbohydrate and protein fractions, energy, in vitro dry matter digestibility (IVDMD) and in vitro methane (CH4) emission in buffalo inoculums with the objective to rank dry roughages for CH4 emission, and to correlate their nutritional constituents with CH4 production.