Metabolomic analysis of oviduct fluid on day 3 post-estrus in Holstein heifers.

The metabolites in the oviduct fluid (OF) of both oviducts were analyzed by proton nuclear magnetic resonance (1H-NMR) in Holstein heifers on day 3 after synchronized estrus. Twenty-six metabolites were quantified, among which lactate, glycine and myoinositol were the most abundant. Six metabolites including glycine and myoinositol varied in amount according to the proximity to the corpus luteum. Glucose and histidine were among the most variable metabolites among heifers while threonine and lactate were among the most stable ones, suggesting different mechanisms of homeostasis in the OF.