Four rams (body weight 50 kg) fitted with ruminal and simple duodenal oannulae were fed at random, in six 14-day periods, rations in a loose (S) and pelleted (G) form, containing 70% of dehydrated maize plant and 0, 1.25 and 2.5% of urea (respectively rations SO, SI, SII and GO, GI, GII). The urea doses were assumed to cover 100 and 200% of the deficiency of rumen degradable N /ARC, 1980/. The duodenal flow of microbial protein N (NBM) was in groups S 8.17, 13,8 and 14.6 g and in G 10.8, 13.7 and 16.1 g/24h. The yield of NBM/100 g O.M. apparently digested in the rumen was, respectively, 1.16, 2.18, 2.00 and 1.66, 2.24, 2.86 g. The effect of physical form on NBM flow and yield was significant (P ˂ 0.05). N-NH₃ level in the rumen fluid was lower in groups S than G, being probably a reason for higher NBM synsynthesis in groups G. Better utilization of urea at its highest level (2.5%) from the pelleted ration can be caused by the decreased degradation in the rumen of feed protein due to pelleting process.