ABSTRACT
Forty lactating Zaraibi does were grouped into 4 feeding treatments for 19 weeks. The
treatments were; G-1: concentrate feed mixture (CFM)+(70% berseem, 25% rice straw & 5%
yellow corn) (S-1); G-2: CFM+(70% berseem, 25% wheat straw, & 5% YC(S-2); G-3:
CFM+(70% berseem, 25% bean straw & 5% YC) (S-3); G-4: CFM+ (70% berseem, 25% corn
stalk, & 5% YC) (S-4). All groups were fed on restricted amount of CFM to cover 50% of the
requirements recommended by NRC (1981) for lactating goats. Yet, the different combinations
of the four silages were fed ad libitum.
The main results indicated significant higher digestion coefficient of most nutrients
with G-3 and G-4 compared with G-1 and G-2. Moreover, TDN and DCP values were
significantly higher with G-3 and G-4 compared with G-1 and G-2. Milk yield was significantly
higher with G-4 (1.397 kg/h) followed by G-3 (1.338 kg/h) then G-2 (1.190kg/h) while the
lowest with G-1( 1.150 kg/h). The effect of different silages studied on milk composition was
not significant. But, somatic cell count (SCC) was correlated negatively with milk yield. The
results indicated that there was no significant variation among different groups regarding milk
quality.
The results indicated also that the highest DM intake was recorded with G-4 (89.89
g/kg W0.75) followed by G-3 (88.40) then G2 (84..35) and the least with G-1 (83.42). In the same
time, the feed conversion efficiency based on DM and TDN was better with G-3 and G-4
compared with G-1 and G-2. Economic efficiency analysis indicate that G-4 (containing corn
stalk silage) was economically better than G-1 and G-2, followed by that containing bean straw
silage.