ABSTRACTThis work was carried out on growing Rahmani lambs to investigate the effect of using silage made from some legume and/or grasses on growth performance as well as some rumen and blood parameters. Thirty lambs divided into 5 groups (6 animals each) were fed ad libitum on Cowpea (CW), Millet×Napier grass hybrid (MN), Cowpea - Millet× Napier grass hybrid (CW-MN), Sesbania sesban (SS) and Sesbania-Millet× Napier grass hybrid (SS-MN) in five experimental treatments. Concentrate feed mixture (CFM) was offered with experimental groups to cover 1% of body weight. The feeding trial lasted 112 days. Three lambs of each group were involved in digestion trial to evaluate the feeding values of the tested diets. Results showed that, DM, CP and EE were higher and NFE was lower in SS and CW than MN. The highest OM content was recorded with SS (90.50%) while, CW recorded the lowest value (86.60%). The digestion coefficients of OM, CF and CP of mixture silage (CW-MN) and (SS-MN) were significantly (P<0.05) higher than the other silage groups (CW, MN and SS). The same trend was observed also with DM, EE and NFE digestibility. Thus, the TDN values of both of CW and MN were significantly lower compared with their mixture silage (CW-MN). Similarly, the TDN value of SS-MN mixture silage was significantly (P<0.05) higher than those in SS and MN single silages. The highest value of DCP was recorded with SS (14.95) followed by CW (14.19), SS-MN (12.74) and CW-MN (11.84) and the lowest with MN (7.01) where all differences were significant. The daily feed intake tended to increase with SS-MN group (69.0g/ kgW0.75) and CW-MN group (68.56g/kgW0.75) compared with the other silage groups. The highest value of water consumption was recorded with SS group whereas, CW-MN group recorded the lowest value. The effect of legume or grass silage and their mixtures on some rumen parameters were significant. Whereas, the effect of silage treatments on most blood parameters were not significant.As for growth rate, the highest value was recorded with group SS-MN (137g) followed by CW-MN (133g), SS (124g) and CW (120g) and finally MN that recorded the lowest value (115g). The differences among groups were significant. The same positive effect of mixtures silage was observed also with feed utilization efficiency based on DM and TDN. Accordingly, it could be recommended to using mixtures silage such as SS-MN and CW-MN in growing sheep rations owing to their positive effect on growth performance.