In El-Abd dairy farm- Sherbeen Dakhahlia governorate 12 dairy Freisian cows 4 years old were signed randomly into two groups as control group and experimental one. The experimental group was given in addition to the control ration sodium biocarbonate 0.8%. The milk yield revealed slight increase in the cows given NaHCO with significant increase in the percent of dry matter
intake after 2nd, 3rd & 4th weeks post partum. Blood analysis showed an increase in blood urea nitrogen and in blood serum calcium as a result of giving NaHCO, in the ration while the rest of blood parameters were within the normal physiological limits in both control and experimental group.
Examination of the ruminal juice manifested an increase ammo nia concentration in the experimental group given NaHCOZ. On the contrary propionate and total volatile fatty acids were decreased. The rest of the ruminal juice parameters were within the normal physiological limits in both experimental and control group.