Twenty eight lactating buffaloes were used in a completely randomized design with 2×2 factorial arrangement of four experimental diets including low protein–low energy (LP-LE), low protein–high energy (LP-HE), high protein–low energy (HP-LE) and high protein–high energy (HP-HE). Results showed that the HP-HE diet recorded the highest digestibility coefficients of CP, EE, NFE, nutritive values, TDN and DCP intake, while HP-LE diet had the highest CF digestibility (P<0.05). The HP-HE diet had the highest (P<0.05) actual milk and 7% FCM yield and the contents of protein, lactose, SNF and TS in milk, HP-LE diet had the highest fat content (P<0.05). The HP-HE diet showed the lowest amounts of DM and TDN per kg, 7% FCM, while LP-HE diet had the lowest amount of DCP per kg 7% FCM (P<0.05). The LP-HE diet recorded the lowest average daily feed cost, while HP-HE diet showed the lowest feed cost/kg 7% FCM and the highest total revenue and economic efficiency (P<0.05). Buffaloes fed HP-HE diet showed short periods from parturition to first estrus and first service, service period, days open, the lowest number of services per conception and the highest conception rate (P<0.05). Manuscript profile