Productive performance of the animal is directly related with feed intake. Among various nutritional tools used to
improve feed intake, dietary cation anion difference (DCAD) has the most promising effect. The DCAD is the
difference between cations and anions and (Na+ + K+) - (Cl + SO") mEq/100 gm of OM is the most common
equation used for DCAD calculation. High DCAD diet improves the pH of the rumen, required for optimum
cellulytic microbial activity which increases dry matter intake. The rumen pH is a primary factor for controlling fiber
digestion. There is a close relationship between rumen pH and forage digestion kinetics. Extent of cellulose
digestion by microorganisms also depends upon ruminal pH and any change in pH from 6.8 to 6.5 increases lag
time by 2h and on reducing below 6.0, lag time increased up to 8h due to loose attachment of bacteria to plant
cell wall at low pH. The response of the ruminal H+ to high DCAD is very quick. It improves ruminal NH3
-N
concentration, acetate while propionate and butyrate decrease which results in higher acetate to propionate ratio.
Blood pH, HC03". serum cation anion balance (Na" + K+- cr + S--) also tended to increase with increasing DCAD.
It increases urine pH which reflects alteration in blood pH. Milk yield and its composition are also improved as a
result of increased DCAD level in the diet.
M. Sharif, Mahr-un-Nisa, M. Sarwar, M. Aasif Shahzad. (2008) Influence of varying levels of dietary cation anion difference on ruminal characteristics, acid baseStatus And Milk Yield Of Early Lactating Animals (A Review), , Volume-45, Issue-2.
