Relationship between body condition score, blood metabolites, oxidative stress and reproductive performance in transition dairy cows

Abstract

The aim of the current study was to investigate the relationship between prepartum body condition score (BCS), blood metabolites (Glucose, BHB), oxidative stress (MDA, GSH-Px) in transition period and some reproductive parameters in Holstein dairy cows. 50 cows were divided into two groups (low BCS, n=25, BCS = 2.75-3.0 and adequate BCS, n=25, 3.25 ≤ BCS ≤ 3.75) according to BCS on the 21 st day before expecting calving. BCS was also recorded at 0 and +21 days after calving. Blood samples collected at -21, 0 and +21 days from calving for MDA and GSH-Px analysis as well as at -21, +14 and +21 days of postpartum for glucose and BHB. Reproductive parameters obtained from farm records were also collected. MDA concentrations were higher in group of low BCS compared to group of adequate BCS at -21 and 0 d related to calving (p<0.05). GSH-Px activity was lower in group of low BCS than adequate one during the transition period (p<0.05). Low BCS group also showed higher concentrations of BHB at +14 and +21 days after calving. During the transition period, low BCS group had lower glucose concentrations compared to adequate one (p<0.05). Adequate BCS group of cows showed shorter intervals of calving to first estrus (p<0.01) and calving to conception (p<0.01). In conclusion, cows with lower BCS at the prepartum period had worse metabolic and oxidative balance during the transition period. This situation also causes worse reproductive performance in cows.