Abstract Ecocool is comprised of Lactobacillus plantarum (NCIMB 40027). min 6 67x 10 cfu/g and Lactobacillus buchneri (NCIMB 30139). min 1 33x 10 cfu/g. A study to assess the potential contribution of Ecocool in inducing a faster and more efficient anaerobic start-up fermentation through L. plantarum and increasing aerobic stability at feed-out through L. buchneri in mixed grass-legume (Cenchrus purpureus var Kakamega I - Mucuna pruriens) silage at the ratio 3:1, respectively, was conducted at Mahwa National Zootechnical Station. Three forage pre-ensiling treatments were tested in this experiment namely, fresh non-ensiled herbage (control), ensiled without Ecocool (untreated) and ensiled with Ecocool (treated). Forage was ensiled for 1 day and fermentation was completed after 45 days, but the silo was opened after seven months. From 13th October to 24th November 2023, the three different forages were individually fed to nine lactating Friesian cows in a completely randomised design experiment (CRD). Three types of rations were assigned to each group of three dairy cows. To minimize animal selection bias, cows were balanced across treatments with respect to breed type, live weight, milk yield, lactation stage and parity. Daily milk yield was recorded and milk composition was analysed three times during the experiment. Silage analysis revealed that the untreated silage had the highest pH, indicating low quality silage while Ecocool treated silage had the lowest pH. Milk yield differed significantly among treatments (p <0.05). Cows allocated to silage treated with Ecocool had the highest average milk yield (15.75 l/day), compared to those on untreated silage (13.59 l/day), or control (12.35 l/day). Regarding milk quality assessment, there were no significant differences for almost all parameters analysed except proteins (P<0.05). The highest mean protein content was observed from cows fed Ecocool treated silage (3.58 ± 0.48 % DM) and the lowest was from cows assigned to the control (2.78 ± 0.15% DM). Keywords: Aerobic stability, Ecocool, Kakamega I, Milk yield, Mucuna, Silages