A study was conducted to determine nutrients digestibility, ruminal fermentation and blood constituents of growing lambs fed berseem silages. Eighteen growing crossbreed lambs (23.2±0.91 kg average live body weight; 5 months old) were randomly distributed to three experimental groups (six in each). First group was fed starter concentrate feed mixture (CFM) and berseem hay (R1; as a control). Whereas, other groups were fed CFM plus berseem silage supplemented with either 5% ground yellow corn (BSC; R2) or lactic acid bacteria and yeast mixture (BSB; R3) during ensiling process. Blood samples were collected monthly to determine different metabolites. Before finishing the experiment, three digestibility trials were conducted using three lambs for each ration at average body weight 39.0 kg ±0.72 and 9 months of age. Daily dry matter intake (DMI), digestibility and feeding values were calculated. Also, rumen liquor parameters were measured pre- and post-feeding. The results indicated that the DMI appeared to the highest(P<0.05) significant with R2 followed by R3 due to DM% of silage. As well as, the CP intake was the greatest (P<0.05) in R2 than other groups. The digestion coefficient of all nutrients in R2 were significantly (P<0.01) greater in R2 than other rations, except for OM, CP, EE and CF which were slightly higher with no significant differences. Whereas, R3 was the greatest (P<0.01) hemicellulose digestibility and the lowest (P<0.01)of cellulose. The values of TDN, DCP,TDN:CP ratio, ME, NE and CPI:MEI ratio did not vary significantly among treatments. The intake of TDN and DCP were greater (P<0.01) in R2 than other groups, whereas R1 had the highest (P<0.01) value of NFCI and NFCI:DCPI ratio. The quality index of rations was higher (P<0.01) value in R2 compared with other rations. The ruminal pH and effective NDF values were affected (P<0.01) by dietary treatments and sampling time. The highest (P<0.01) value of ruminal ammonia-N recorded with R1 than the others. However, ruminal TVFA's and buffering capacity tended to the lowest (P<0.05) in R1. Blood metabolites did not differ significantly among groups except for blood protein, albumin and globulin which were higher in control than treated groups. It can be concluded that growing lambs fed ration containing CFM plus berseem silage supplemented with 5% yellow corn had higher nutrients intake, digestibility, quality index, ruminal TVFA's and buffering capacity and consequently had the best performance.