The effects of dry period body condition score on some trace minerals, oxidative, and inflammatory indicators in transition dairy cows

Context Body condition score (BCS) management throughout the dry period to calving is one of the strategies that can ensure optimal overall health and high milk yield after parturition. Aim The objective of this study was to evaluate the effects of BCS during the dry period on serum concentrations of some trace elements, oxidative, and inflammatory indices during the transition period of Holstein cows. Methods Fifty multiparous cows were classified based on their dry BCS (scale of 1 to 5) at the beginning of dry period as non-fat (NFC) (BCS <3.75; BCS minimum: 3; BCS maximum: 3.5, BCS means: 3.36; n = 25), and fat (FC) (BCS >= 3.75; BCS maximum: 4.25, means: 3.87; n = 25) groups, and received similar diet and kept under same management condition. Sampling was performed at 14 +/- 2 days before expected calving date and 10, 20 and 30 days after calving. Key results FC had lower zinc (Zn), chromium (Cr), and manganese (Mn) concentrations. Furthermore, iron (Fe) concentrations were significantly higher in FC in comparison with NFC -14 days before parturition. Serum malondialdehyde (MDA) and haptoglobin (Hp) elevated significantly in FC 20 days after calving, whereas superoxide dismutase (SOD) activity was significantly higher in NFC on day 14 before calving. Its activities increased significantly in FC on day30thof lactation. In addition, the highest serum ferric reducing antioxidants power (FRAP) and copper (Cu) and the lowest serum paraoxonase 1(PON1) and iron (Fe) concentrations were observed on day 20th of lactation. Conclusion Serum Zn, Mn, and Cr amounts were significantly affected by BCS. Furthermore, fat cows had more extensively endogenous antioxidant and inflammatory responses. Implication. Our data highlights the fact that although all cellular metabolic, oxidative and inflammatory processes varied at different times of transition period, fat cows are more susceptible to metabolic and health disorders than non-fat animals.