Reducing dietary cation-anion difference (DCAD) has been proved an effective way to prevent milk fever in dairy cows. Based on the similar physiological gastro-intestinal tract anatomy and metabolic process between female goats and dairy cows, this study was conducted to evaluate the effects of varying DCAD on fluid acid-base status, plasma minerals concentration and anti-oxidative stress capacity of female goats. Urinary pH, plasma Ca, P and Mg; and anti-oxidative stress indices of total superoxide dismutase (T-SOD), hydrogen peroxide (H_2O_2), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA) were determined to evaluate the effect. Forty-eight Guizhou black female goats ((15±1.9) mon of old, (22.3±3.75) kg of BW) were randomly allocated to 4 blocks of 12 goats each and were fed 1 of 4 diets differed in DCAD level (calculated as Na+K-Cl-S, mEq kg^(-1) DM). Levels of DCAD were preliminarily designed to be control (+150 mEq kg^(-1) DM, CON), high DCAD (+300 mEq kg^(-1) DM, HD), low DCAD (0 mEq kg^(-1) DM, LD) and negative DCAD (-150 mEq kg^(-1) DM, ND), respectively. A commercial anionic salts (Animate) and sodium bicarbonate (NaHCO_3) were supplemented to reduce and increase DCAD level, respectively. There was no difference in dry matter intake for 4 groups of goats. Urine pH was aggressively decreased (P<0.0001) with reduced DCAD and there was a strong association between DCAD and urine pH (R^2=0.793, P<0.0001). Compared with CON and HD feeding of LD and ND resulted in greater (P<0.05) plasma Ca concentration. Plasma P level was increased (P<0.05) when anionic salts were supplemented. The DCAD alteration did not affected (P>0.05) plasma Mg level. There was no significant (P>0.05) difference in plasma GSH-Px activity and H_2O_2, but anionic salts supplementation in LD and ND significantly increased (P<0.05) plasma T-SOD activity and tended to reduce MDA (P<0.1) over HD and CON. Results from this study indicated that reducing DCAD could decrease urine pH and increase plasma Ca concentration of female goa
