Effect of undegradable dietary protein levels and plane of nutrition on feed intake, water metabolism and blood biochemical constituents in crossbred heifers

The present study was conducted to discern the effect of concentrate mixture containing 2 UDP levels from plant sources at 2 planes of feeding on feed intake, weight gain, water metabolism and certain haematobiochemical constituents in crossbred heifers. An experiment was conducted in crossbred heifers (16), 15 to 19 months old, randomly divided into 4 groups of 4 each in a 2 × 2 factorial completely randomized design and were fed 4 dietary treatments for 116 days. Mixed oat green and oat hay sewed as roughage. The average daily dry matter consumption did not differ significantly among groups. The heifers in treatment group 3 fed high UDP ration at higher plane of feeding gained highest daily body weight (0.80 kg) followed by treatment groups 4 (0.75 kg), 1 (0.67 kg) and lowest in heifers in treatment group 2 fed low UDP ration at normal plane of feeding (0.59 kg). The daily body weight gain was improved by 10.45% due to high UDP ration and 23.8% due to higher plane of feeding. The daily water intake and water excretion did not differ significantly amongst the groups. However, water loss was more in faeces and less in urine due to high UDP ration but plane of feeding had no significant effect. The blood serum concentration of total protein, albumin, globulin, cholesterol, calcium and phosphorus and activities of SGOT, SGPT and serum alkaline phosphatase did not differ significantly amongst the treatment groups, however, there was higher concentration of serum total protein, calcium content and SGPT activity due to high UDP ration. The higher plane of feeding also increased serum albumin and phosphorus content and SGPT activities significantly. It is concluded that feeding high UDP ration (50: 50 RDP: UDP ratio) with 115% of nutrients as recommended in NRC 1989) feeding standard under Indian condition is advantageous in improving the weight gain in crossbred heifers at later stage of growth without affecting the feed and water intakes and with normal blood biochemical constituents.