24 weaned Yankasa lambs (12 males and 12 females) aped between 6 and 9 months and weighing between 10.3 kg and 27. 8 kg were used for the experiment. The animals balanced for weight were randomly alloted to four treatments with each treatment consisting 3 ram - and 3 ewe - lambs. The four treatments were designated High-high (HH), High-low (HL), Low-high (LH) and Low-low (LL) respectively depending on the protein level in each ration. The HH and LL groups received high protein ration (12.1% crude protein) and low protein ration (ff.1%)crude protein) respectively for the entire period of the experiment. The HL and LH grOUPS received high protein ration and low protein ration during the first 100 days of the experiment but were switched over to low and high protein rations respectively for the remaining 84 days of the experiment, The daily feed intake of each pen was determined. All the animals were weighed fortnighly.Two digestibility trials were carried out during the first half and two in the second half of experiment usinp the male animals. At the end of the experiment, all the animals were slaughtered, dressed and jointed into 9 cuts. Each cut was completely dissected into muscle, fat and bone. During the first half of the experiment, the animals on high protein diet treatment consumed less feed than those on low protein diet. After the changeover (Days 100 to 184), the LH animals, consumed more feed than, the HH animals. HL animals also had a higher feed intake than animals on LL treatment. For the entire period of the experiment, LH and HL animals consumed more feed than HH and LL animals respectively. The feed intake of the males was higher than that of the females throughout the period of experiment. The drymatter, nitrogen and energy digestibility coefficients of the high protein ration were higher than those for low protein ration during the first half of the experiment but at the point of change-over (3rd digestibility trial), the low protein ration had higher drymatter and energy digestibility coefficients while there was no significant difference between the two rations in nitrogen digestibility. During the 4th digestibility trial which was conducted towards the end of the experiment, the hifrh protein ration had higher digestibility of drymatter, nitrogen and energy than the low protein ration. The efficiency of utilization of drymatter, crude protein and energy war, higher in the bigh protein diet treatments than in the low protein diet treatments. The overall efficiency of drymatter and energy utilization was highest for HH animals followed by the LH group while animals on LL treatment were least efficient. LH animals had the highest efficiency of crude protein utilization. The high protein diet had about 3.3 times as good feed conversion as the low protein diet. LH and LL animals had a better feed conversion than animals on HH and HL treatments respectively during the second half of the experiment. In all, HH animals had the best feed conversion, followed by LH animals while animals on LL treatment had the lowest feed conversion. The males had a better feed conversion than the female animals throughout the experiment. The cost of feed per kg liveweight gain for animals on low Protein diet was N2.1 more than for those on high protein diet during the first half of the experiment. HH animals cost N0.3 more than the LH group in Producing 1 kg liveweight pain durinp the second half. However, on the whole, it cost N0.1 more in LH animals per kg liveweight gain than in HH animals. LL animals had the highest overall cost of production per kg liveweight gain while HL animals cost N0.4 more than the LH group in the production of 1kg liveweight gain. The carcass weight of HH and HL animals were 1.2 times higher than those of animals on LH and LL treatments respectively. The dressing percentage, percents total fat and total muscle were higher in the high protein ration than in the low protein ration. Animals on HH treatment had 4.5% more Percentage of total fat than LH animals while HL animals had 3.1% more percent total fat than the LL groun. Also, relative to the carcass weight the LH animals had more muscle than the HH group. Thus, the LH animals proportionately had more muscle and less fat than the animals on HH treatment. There was more percentage of total muscle and total fat in the males than in the female animals.