Saliva and plasma metabolome analysis during the five days before foaling in the mare

The aim of this prospective study was to analyze the metabolome of equine saliva in the last five days before foaling, with a focus on identifying metabolites whose level significantly changed just before parturition, that could be potential salivary biomarkers of the onset of parturition. We compared the saliva and plasma metabolomes to investigate the relationship between these two biofluids according to the physiological stage. Saliva and blood samples were collected from twelve mares once a day in the morning, from 322 days of gestation to the day of foaling. Samples collected from four days before the day of parturition to the day when parturition occurred were analyzed by 1H Nuclear Magnetic Resonance (NMR) spectroscopy.