Evaluation of blood minerals and oxidative stress changing pattern in prepartum and postpartum Achai and Holstein Friesian dairy cows.

This research focused on evaluating blood mineral levels and malondialdehyde (MDA) as an indicator of oxidative stress before and after giving birth in Achai and Holstein Friesian (HF) dairy cows. Blood samples were obtained from a total of 50 cows representing both breeds on the third, second, and first week prior to calving, as well as on the day of calving (day 0). Subsequently, samples were collected on the 1-3 weeks postpartum to allow a comprehensive evaluation of blood parameters throughout the peripartum period. Results showed a significant (p < .01) decrease in serum zinc (Zn) levels on the day of parturition in both breeds. Additionally, HF cows exhibited higher (p < .01) Zn levels on week 2 before giving birth. Interestingly, blood selenium (Se) concentration increased (p < .01) in HF cows on weeks 2 and 3 after calving. In contrast, Achai cows showed a rise (p < .01) in blood Se on week 3 of parturition. Blood copper (Cu) levels were higher (p < .01) on weeks 2 and 3 after parturition in HF cows and on third week before parturition compared to Achai cows, where serum Cu remained high on week 1 of parturition. The findings indicated that blood magnesium (Mg) was higher (p < .01) on third week before parturition in Achai cows and on weeks 2 and 3 after parturition. Serum calcium (Ca) was higher (p < .01) in both HF and Achai cows on weeks 2 and 3 after parturition, and lower (p < .01) on third week before giving birth in both breeds. The mean blood MDA levels in Achai cows were lower (p < .01) on weeks 1 to 3 postpartum or 3 weeks before giving birth. In HF cows, serum MDA increased (p < .01) just before 2 weeks of parturition and remained elevated until 3 weeks of parturition. Thus, both breeds exhibited a similar pattern of mineral fluctuations; yet, Achai cows demonstrated greater resilience to oxidative stress compared to HF cows during the transition period.