Abstract: The two experiments were conducted with the overall objective of adapting Holhiem Gas System (HGS) to working conditions in the East and Central Africa (ECA) Region. The first experiment employed rumen contents from abattoir as source of rumen fluids and inoculum for feed evaluation. The second trial determined fermentation kinetics and Metabolisable Energy (ME) contents of seven forage species/accessions under preliminary trials at the Rwanda Agricultural Board (RAB), Karama Research Station. Results showed that Organic Matter Digestibility (OMD) and ME contents derived from gas production technique (GME) were highly correlated with Tilley and Terry In Vitro Organic Matter Digestibility (IVOMD; R2 = 0.73) and ME derived from IVOMD (TME) (R2 = 0.92). The obtained values were used to estimate ME and kinetic coefficients of 17 improved forages available in Rwanda as a contribution to the on-going exercise of developing the ECA feed database and national forage germplasm development. Using cluster analysis 14 promising forage accessions were identified for next phase of evaluation in other agro-ecologies across the country.