Effect of Higher Plane of Nutrition on the Performance of Pregnant Crossbred Heifers

To asses the influence of dietary protein levels on the performance of pregnant heifers, 12 crossbred heifers at mid pregnancy (331 kg ± 12.20 kg, B. W.) were divided into 3 equal groups and offered concentrate mixture (19.78% CP), wheat straw and green fodder. The animals of control group T₁ were fed as per NRC (1989) and those in T₂ and T₃ were fed 10 and 20% higher CP, respectively, than those of T₁. There was no effect on DMI in the three groups, but R: C ratios narrowed from T₁ to T₃ groups. Body weight gain of heifers and calf birth weight were higher (P<0.05) on feeding 10% higher CP. DCP and TDN of the ration was higher (P<0.05) in T₂ than that of control group, but at par with T₃. Similarly, DCP intake of T₂ (716 g) and T₃ (735 g) were higher (P<0.05) than T₁ (637 g). There was no effect on DM, OM, NDF, ADF and hemi-cellulose digestibility among groups, whereas that of CP, EE and NFE was higher (P<0.05) in group T₂ however, reverse trend was observed in case of CF digestibility. Milk yield and 4% FCM yield increased (P<0.05) in T₂ than that of T₁ and T₃. Present investigation revealed that feeding of 10% higher CP over NRC (1989) to the pregnant heifers increased (P<0.05) the body weight gain, calf birth weight, nutrients digestion and milk production.