EFFECTS OF ESTROGENIC SILAGE ON SOME CLINICAL AND ENDOCRINOLOGIC PARAMETERS IN OVARIECTOMIZED HEIFERS

The influence of phytoestrogens was studied in 3 ovariectomized Swedis h Friesian heifers fed 20 kg of 100% red clover silage per heifer/day for 14 days. Behaviour, reproductive organs and pituitary response to exogenous gonadotropin-releasing hormone (GnRH) injections were monito red. Clinical effects like oedema and mucous discharge in the vulva, p resence of milky fluid in the mammae and increases in teat size and th e cross-sectional distance of the uterus were observed in heifers fed red clover silage. Fluid accumulation in the uterus, visualized by mea ns of ultrasonography, had still not disappeared 30 days after the red clover silage had been completely withdrawn. Red clover silage appear ed to reduce the magnitude and duration of the pituitary response to G nRH injections.