In this study, the investigation of serum oxidative stress index (OSI), paraoxonase 1 (PON1) activity, total antioxidant (TAS) and oxidant status (TOS) levels in colostrum period of dairy cows was aimed. It was used sixteen Simmental cows for blood samples as follows: within 0, 1, 2, 3 and 4 days postpartum (group I, II, III, IV and V, respectively). Serum TAS, TOS and PON1 activity levels were determined by spectrophotometric methods. The results showed that oxidative stress in group IV was higher than group I and II. PON1 activity in group V was significantly higher than other groups. It was concluded that serum oxidative stress and PON1 activity levels in colostric period of dairy cows changed daily.
Dairy Cows, Colostrum, Oxidative Stress, Paraoxonase