Abstract
Twenty male crossbred ($Sahiwal{\times}HF$) calves of about 6-9 months of age were divided into four groups of five animals each. All the animals were offered wheat straw ad lib. As the basal feed. However, animals in group I were fed concentrate mixture while the animals in groups II, III and IV had free access to urea molasses mineral block (UMMB) lick (I), (II) and (III) respectively as a partial substitute of concentrate mixture. The average concentrate offered (kg/day) to the animals was significantly (p<0.01) higher in group I ($2.69{\pm}0.18$) compared to groups II ($1.76{\pm}0.15$), III ($1.70{\pm}0.06$) and IV ($1.65{\pm}0.12$). The UMMB lick consumed was non-significantly different amongst groups I ($535.40{\pm}38.14$), II ($525.60{\pm}31.82$), III ($551.00{\pm}38.49$) and IV ($548.80{\pm}45.46$). Except ether extract, the digestibility coefficients of CP, ADF and NDF were non-significantly different in different groups. Similarly, N balance (g/day) and percent N retention of intake was not affected in different groups on supplementation of UMMB lick. Body composition of animals was similar in different groups supplemented with either concentrate mixture or concentrate mixture and UMMB licks. It may be concluded from these studies that UMMB lick can partially replace the concentrate mixture in the diet of growing calves without affecting the growth rate, nutrient utilization and body composition. The UMMB lick, thus, can form a part of the ration economically in the diet of growing ruminants especially in developing countries.