Effect of Concentrate Supplementation on Intake, Digestion and Milk Production in Crossbred Cows Grazing on Native Pasture of Tripura

Four lactating crossbred (Jersey & Local) cows were randomly distributed into4 groups in an experiment based on latin square design comprising of 4 periods of 5 weeks each in which 2 weeks were adaptation period. Group J (Control) were stall fed on paddy straw, thin napier grass and concentrate as per their requirements. Other groups were on grazing for 6 h/d besides providing paddy straw and concentrate supplementation at the rate of 1, 2 and 3 kg in group II (T₁), III (T₂) and IV (T₃), respectively. Straw intake was 3.10, 2.99, 3.04 and 2.35 kg/d; forage/pasture intake was 0.95, 5.01, 4.04 and 3.15 kg/d and total DMI was 8.05, 9.00, 9.08 and 8.50 kg/d in control, T₁, T₂ and T₃ groups, respectively. Both straw and pasture consumption were significantly (P<0.01) reduced in group T₃. Total DMI was higher (P<0.01) in groups T₁ and T₂ than in control and T₃. Grazing tame was 263 min., in groups T₁, which was reduced with increased level of concentrate, however, bite size and bitting rates remained similar among the groups. OM digestibility was 66.76, 68.09, 71.86 and 66.26 percent In control, T₁, T₂ and T₃ groups, respectively and the variation among groups was significant (P<0.01). Daily milk yield was 5.85, 5.05, 7.08 and 6.50 kg in control, T₁, T₂ and T₃ groups, respectively and the difference was significant (P<0.01). This indicated that 2 kg concentrate supplementation could be optimum for cows producing 7 kg milk/d grazing on native pasture of Tripura.