Digestibility and Nutrient Utilization Efficiency in Crossbred Calves as Influenced by Feeding Alkali Treated Rice Husk With or Without Urea

Twenty male Karan Fries calves were randomly divided into 4 equal groups. DCP requirement of all the animals was provided through concentrate mixture except in group D where 30% of total DCP requirement was met with urea. In group A, wheat straw was offered ad lib, whereas in groups B, C and D, 33, 66 and 33% of wheat straw was replaced by rice husk treated with 5.0% NaOH and the excess alkali subsequently neutralized with hydrochloric acid. Tn group D, treated rice husk was impregnated with urea before feeding. DM intake was significantly lower in group D, but the roughage intake did not differ (P > 0.05) in the four groups. Except for CP and EE, the digestibility coefficients of proximate principles and different fibre fractions in all the four groups were similar. The CP digestibility was higher (P< 0.01) in group D, but EE digestibility was higher (P<0.01) in groups B and C as compared to other groups. The feed-gain ratio, protein retention efficiency and gross energetic efficiency in groups B, C and D were similar to the control group. N balances were positive in all the groups but the value was highest in the control group. Ca and P balances were also positive in all the groups and were not affected by the treatment.