Variations of some adipokines, pro-inflammatory cytokines, oxidative stress biomarkers, and energy characteristics during the transition period in dairy cows

Limited information exists about the relationship of adipose tissue with inflammation, oxidative stress, and energy metabolism during the transition period in dairy cows. The objective of this study was to assess the changes and relation of some adipokines, cytokines, oxidative biomarkers, and serum biochemical parameters related to energy balance (EB) in cows during the transition period. Thirty multiparous Holstein cows were selected based on estimated parturition date, and blood samples were collected from jugular vein on one-week prepartum and one and three weeks postpartum and used to measure the parameters. The serum levels of beta-hydroxybutyric acid (BHB), non-esterified fatty acid, cholesterol, high-density lipoprotein (HDL), aspartate aminotransferase, and total antioxidant capacity increased significantly, and glucose, urea, triglyceride (TG), and low-density lipoprotein (LDL) decreased significantly after parturition. The serum values of adiponectin, resistin, leptin, and cytokines including interleukin 6 (IL-6) and tumor necrosis factor (TNF)-α were not changed significantly during the experiment. The results of the Pearson correlation revealed a significant negative correlation between BHB with glucose, albumin, cholesterol, HDL, LDL, and a positive correlation with TG and malondialdehyde. Also, there was a significant direct correlation between insulin and leptin, adiponectin, resistin, IL-6 and TNF-α in the whole experiment period. These emphasize the difficulty of dairy cows to manage the energy requirements during the transition period. It can be stated that adipokines and cytokines may have an essential role in the metabolic status in this period, and control of their production and, or secretion could be helpful in EB during the transition period.