The efficiency of N utilization from four complete rations formulated with groundnut cake (CR-1), salurea-90 (CR-2), urea + deoiled salseed weal (DOSSM) (CR-3) and groundnut cake + DOSSM (CR-4) were compared in a 4x4 latin square design using Nellore brown wethers. The N retention was similar in all the treatments. The rumen pH was lower (P<0.01) in wethers fed CR-4 than those fed CR-1 or CR-2, irrespective of sampling time. The rumen ammonia-N (RAN) was correlated with blood ammonia-N (BAN) (P< 0.10) or BUN (P<0.01) in wethers fed CR-2. Significant correlations were observed in RAN vs. BUN (P<0.05), rumen pH vs. BUN(P<0.05) and BAN vs. BUN (P<0.10) in urea fed wethers.
