Phytoestrogen coumestrol and its metabolite in mares' plasma after clover mixed pasture and alfalfa pellets ingestion

摘要: Phytoestrogens are estrogens present in forages fed to horses. Phenolic rings phytoestrogens enable their binding cells estrogen receptors and may compete with 17-β-estradiol influence the estrous cycle. The aim of study was determine whether from clover mixed pasture alfalfa mare s plasma after ingestion. In experiment I, Lusitano mares (n = 14) kept on pastures grasses were bled monthly, November March. Pasture collected, lyophilized frozen. Experiment II, stabled 6) increasing amounts pellets (from 250 g 1 kg/day), added regular feed, for 14 days. They before inclusion (control), days 13 at 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, 6, 7 8 hours feed intake. Coumestrol its metabolite 4 -metoxycoumestrol concentrations determined feeds by HPLC. Data analyzed one-way ANOVA. samples, being highest concentration. decreased until March (P < 0.01). However, they always identified mares’ plasma, regardless feeding system. both active conjugated forms coumestrol higher than control samples 0.05). (free form) rose reached a peak 3.5 h ingestion 0.05), while form peaked 1.5 0.001). free 5 These findings show that, mare, increase blood estrogenic plants Further studies should be carried out evaluate reproduction mares.