ABSTRACT
The effect of dietary yeast culture (YC) supplementation during pre-mating and gestation periods on reproductive performance and some blood constituents were studied on 39 Damascus does aged 3-4 years and weighed 45.87±1.00 kg. The animals were divided into 3 comparable groups (13 does each). The 1st group fed a basal ration composed of 60% concentrate feed mixture (CFM) plus 40 % clover and rice straw. The 2nd and 3rd groups fed respectively the same basal ration plus daily supplement of 2.5 or 5.0 g YC which added to a part of the ground CFM. Results showed that YC supplementation significantly (P<0.05) improved reproductive ability, conception rate, fertility, fecundity, prolificacy, kids born/does joined, kids weaned/does kidded, kg of kids born or weaned/does joined or /does kidded. It also resulted in higher (P<0.05) serum total protein, albumin, total lipids, creatinine, zinc concentrations and AST activity but it decreased cholesterol and urea concentration than control does. Serum total protein, albumin concentrations and A/G ratio were increased (P<0.05) and globulin concentration was decreased (P<0.05) during the last weeks before kidding. AST activity significantly decreased (P<0.05) from mating up to wk 8, thereafter increase was mild and gradual till kidding.. Meanwhile ALT concentration recorded its minimum value at the 10th wk of pregnancy while it increased gradually till kidding. Serum total lipids concentration was significantly decreased (P<0.05) from mating till kidding Total cholesterol concentration was significantly increased (P<0.05) from mating up to the 8th wk of pregnancy, thereafter it was gradually decreased till kidding. Concentration of blood urea recorded its minimum value at the 10th week of pregnancy (mid pregnancy). Thereafter it gradually increased till 18th week and decreased till kidding. Meanwhile, serum creatinine concentration increased gradually from conception till kidding. The concentration of serum Zn recorded its maximum value at the 8th week of pregnancy, thereafter it gradually decreased till kidding. However, the concentration of serum Fe recorded its minimum value at the 14th week of pregnancy, thereafter it gradually increased up to the 18th week and decreased till kidding.It can be concluded that yeast culture supplementation could be added to does ration at the level of 2.5 or 5.0 g/head/day during pre-mating and gestation periods in order to improve reproductive traits and blood components.