Forty Ossimi male lambs with an average live body weight 3.85 ± 0.25 kg and 7 days age were randomly assigned to four feeding groups, each of 10 animals to be weaned early at 8 weeks of age. The different experimental groups were supported by a creep feeding ration from the second week of age until being weaned, besides dam's milk. After weaning, lambs were depended completely on the starter ration for another four weeks (12 weeks old). Rations were characterized by no fiber source (control) or inclusion of 5 % different dietary fiber sources, i.e. bean straw (Bs), wheat straw (Ws) and peanut hulls (PnH) which resulted in four isonitrogenous and caloric rations. Data indicated insignificant intake differences among the different tested groups in both milk and solid diets in the first 8 weeks of age. Also, data pointed out both R3 and R4 showed significantly heavier (p > 0.05) final live body weight, highertotal and daily body weight gain compared with R2 but without significant differences with R1 (nil roughage source). From 9-12 weeks of age lambs in R1 recorded higher creep feeding intake without significant differences with R3 and R4 while R2 recorded the lowest feed intake value. Lambs in R3 recorded heavier (P > 0.05) final live body weight, total body and daily weight gain in comparison with the different feeding groups. Results of digestibility trials which carried out after 12 weeks of lambs age for the tested rations pointed out to higher digestibility coefficients and nutritive values  in different terms in favor of R1 (starter without roughages) followed by R3 (Ws), R2 (BS) and later was the (Pn H) ration (R4), respectively. This matter might suggest that (Pn H) roughage source was not a suitable roughage source