Effect of feeding urea ammoniated rice straw with varying JeveJs of cottonseed-cake on the performance of crossbred heifers

The experiment was designed to study the effect cif supplementing urea treated rice straw with four levels of cotton seed-cake to provide 15.0 (T 2 ), 30 (T 3 ), 45 ( T 4 ) and 60.0 (T 5 )% of crude protein (CP) requirements in comparison to a control ration of untreated rice straw supplemented with a concentrate mixture (T 1 ) (0 balance the ME and CP requirements of growing heifers in a randomised block design. The DMI through roughage components as well as digestibility coefficients for DM, OM, NDF, hemicellulose and energy were Significantly (P<0.05) higher for treated straw rations. The average body weight gains for T 1 T 2 , T 3 , T 4 and T 5 were 391.4, 325.6, 368.6, 471.6 and 494. 4g/day, respectively, with the differences between body weight gains significant (P<0.05). Treated straw supplemented with cotton seed-cake to supply 45% of CP requirements resulted in optimum body weight gain at lowest feed cost in growing heifers.