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Enteric methane emissions (eCH 4) from ruminants are the main source of greenhouse gas (GHG) from the livestock sector in sub-Saharan Africa (SSA). The SSA countries face significant challenges in assessing their climate commitments in the livestock sector, particularly in terms of mitigation measures due to the lack of accurate GHG data obtained through in vivo measurements. The objective of this study was to directly measure and analyze eCH 4 in pastoral and agropastoral systems using an advanced methodology: the GreenFeed® system. Different ruminant feeding strategies were tested with the aim to identify those that contribute to the reduction of absolute emissions, emission yield, and emission intensity. Cattle were fed natural rangeland fodder, cultivated forage (green and hay), and combinations of grass with main crop coproducts or legume tree forage. Data collection lasted 2.5 years and included 35 trials (diets). Each trial lasted 3 weeks and was split into 2 weeks of diet adaptation and 1 week of data collection. The dry matter (DM) intake in animals was 20 ±2.4 (12 to 29 g/kg of body weight per head), the DM digestibility, 48 ±4.6 (30 to 70%), and the eCH 4 emissions, 70±17.8 (28 to 114 g/d per head). Green herbaceous forage and tanniferous forage, such as legume tree forage and legume crop co-products, showed good potential to increase livestock productivity and reduce eCH 4 emissions yield by up to 33%. These results will help policymakers promote clean technologies and sustainable livestock practices in SSA, and help implement the IPCC Tier 2 methodology to accurately estimate emission factors by cattle categories and breed s.