Five dietary treatments in three trails were conducted with Barki sheep as follows: 60% Concentrate feed mixture (CFM) and 20% Ammoniated wheat straw ( AWS) as basic diet with 20% Cassava (C) in T1, 20% Prosopis juliflora  (P) in T2, 20% Acacia Saligna (A) in T3, 10% C + 10% A in T4 and 10% C + 10% P in T5.  In Trial 1, Fifteen Barki rams (43± 1.85 kg) divided into equally five treatment groups to evaluate the effect of condensed tannin sources on apparent nutrients digestibility. The results indicated that the rams fed with T3 (20 % A. Saligna) at a maximum level of tannin (8.33 g /Kg DM) had a lower DMI (9.72 %) than the comparable group (T1) (P<0.05).  Lower level of CT (3.87g/Kg) in T2diet have higher the digestibility coefficient (P>0.05) of DM, OM, CP, EE and CF than that on T1 diet by 3.90, 3.57, 1.87, 3.16 and 1.04%, respectively. Rumen ammonia concentrations were decreased with increasing of CT content in experimental diets (T3, T4, T1, T5 and T2, respectively).In Trial 2, Twenty five healthy Barki ewes at late pregnancy, weighing 41±2.29 kg at 3-5 years of age were randomly allocated into five dietary treatments to determine the milk yield and composition and some blood components changes due to tannin sources and productive performance of their offesprings. There was a significant increase (P<0.05) in milk yield with decreasing level of CT (6.42%) for ewes fed T2 ration when compared with the T1 group and there is no considerable variability in milk composition traits among all groups. And no significantly differences in average live body weight (ALBW) of offesprings among the all groups. The experimental diet T2 and T5 had significant increased (P<0.05) total protein and globulin (G) compared with the other experimental diets. No significant differences among different treatments regarding albumin was observed. Groups T3 and T4 have higher levels (P<0.05) of Urea-N and Creatinine when compared with the other groups. Values of AST and ALP were significantly higher (P<0.05) for the ewes in group T3 as compared to all groups, and the highest values of ALT were recorded (P<0.05) with T3.In Trial 3, Twenty-five healthy male Barki lambs after weaning, weighing 12±0.64 kg, aged 3- 4 month divided into five groups to evaluate the effect of tannin sources on growth performance and some blood components. The lambs fed diets T2 and T5 produced totally (P<0.05) higher final live body weight (29.03 Kg and 28.16 Kg, respectively) at the end of the experimental period (90 days) compared to the other groups.  The results indicate that the experimental tanniniferous plants can be incorporated up to 20 % with ammoniated wheat straw without compromising the body health of the animals and the best impact of tanniniferous plants on the performance of Barki sheep was Prosopis juliflora  (leaves & twigs), Cassava and Acacia Saligna, respectively.