Assessment of Plasma Oxidative Stress Biomarkers and Metabolic Parameters of Dairy Heifers: Relationship with Success at First Service

Abstract

First insemination success is considered as good indicator of heifer fertility to ensure renewal of dairy herds. The objective of this study was to determine the relationship between first insemination success and biomarkers of oxidative stress (OS). A total of 25 heifers were divided into two groups according to their success at first insemination: group FS+ (heifers that were pregnant at first service, n = 14) and group FS- (heifers that were not pregnant at first service, n = 11). The serum of these two groups were analyzed for malondialdehyde (MDA), glutathione S-transferase (GST), reduced glutathione (GSH), glutathione peroxidase (GPx), catalase (CAT), myeloperoxidase (MPO), nitric Oxide (NO) and superoxide dismutase (SOD) as oxidative stress biomarkers and biochemical parameters. Heifers in the group FS+ showed no significant difference in all OS parameters compared to heifers in the group FS-. The OS parameters showed almost similar values in both groups except for GST and CAT where the difference was at the limit of significance. The plasma concentration of OS biomarkers assessed in our study were not related to first service success in heifers. Further studies are needed to clarify the role of oxidative status in the reproductive performance of heifers.