
Keywords: Manure; Matrix effects; Estrogens; Conjugated; Chromatography; Mass spectrometry; 13C-gE2; 13C-labeled estradiol glucuronide; 13C-sE2; 13C-labeled estradiol sulfate; fαE2; alpha estradiol-free; dfE2; deuterated free beta estradiol; 13C-fE2; 13C-labeled f