The current study aimed to produce pectinase to be involved in rations of lactating buffaloes. The maximum production of pectinase by A.niger was achieved at 16% sugar beet pulp concentration, inoculum size of 5%, 48 hr of incubation period, initial pH of growth medium 7.0, yeast extract as a nitrogen sources at a concentration of 0.33 g N/l. Two experiments were carried out to evaluate the effects of fibrolytic enzymes supplementation on in vitro degradation of sugar beet pulp and in vivo nutrients digestibility, milk yield and its composition by mild-lactating buffaloes. In the in vitro experiment, dry matter and organic matter disappearance were determined for sugar beet pulp supplemented separately with laboratory produced fibrolytic enzymes (Asperozym) and commercial fibrolytic enzymes source (Tomoko) at 3 levels (0, 1, 1.5, and 2 g / kg DM). Increasing the Asperozym and Tomoko supplementation levels up to 2g/kg DM exhibited the highest (P0.05) values of IVDMD and IVOMD. In the in vivo experiment, fifteen mild-lactating buffaloes after 3 months of parturition were divided into three groups, five animals each, using complete random design.