This trial was conducted for a period of 90 days at the Livestock Experiment Station, Bahadurnagar, Okara, Pakistan during September - November, 2002. Eighteen lactating buffaloes were divided into three groups A, B and C, with six animals in each group. Animals of Group A were fed a concentrate ration with 2 ml of Biovet per kg of feed, while those of Group B were fed an experimental ration having probiotic 500 gms in 100 kg of concentrate mixture. The Group C animals served as control group. The average daily milk yield was 7.60, 7.39 and 6.15 litres in groups A, B and C, respectively. The corresponding values for milk fat were 7.60, 7.39 and 6.15 percent. The daily feed intakes for concentrate mixture were 4.36, 4.38 and 4.41 kg, while fodder intakes were 35.28, 35.29 and 37.46 kg in respective groups. The values for feed efficiency per kg were 1.70, 1.75 and 2.14 on dry matter basis, 0.197, 0.203 and 0.251 on crude protein basis, while 1.05, 1.08 and 1.35 on TDN basis in Groups A, B and C, respectively. It was also observed that under same feeding and management conditions, the lactating buffaloes supplemented with Biovet (Group A) produced more milk @ 1.45 litres per day, while Group B buffaloes supplemented with probiotic produced 1.22 litres more milk per day than Group C. There was a significant (P<0.05) difference in milk yield between groups A and C, and B and C, while these differences were not significant for average daily feed intake and feed efficiency on crude protein basis. The Biovet (BM-Technology) has favourable effect on milk yield and feed efficiency due to beneficial micro-organisms (BM) and combined function for increased digestibility of concentrate mixture and fodder in lactating buffaloes.