| Abstract: | For this investigation 50 Brown Swiss cows from 21 different farms were used. Twenty-five peripartal overconditioned cows (back fat thickness > 38 mm) were compared with 25 peripartal not overconditioned animals (back fat thickness < 38 mm). On days 20, 30 and 40 post partum the ovaries were examined sonographically and 10, 15, 20, 30 and 40 days after calving plasma concentrations of progesterone and 17-beta estradiol were determined. In peripartal overconditioned animals 12 ovarian cysts were found while only one cyst was present in not overconditioned cows (P < 0.05). At first examination all ovarian cysts were classified by ultrasound as follicle theca cysts (progesterone < 0.5 ng/ml plasma). Follow examinations resulted in 3 cysts which persisted as theca cysts while 8 cysts became luteinized and 2 cysts completely regressed. There was no indication of increased plasma progesterone and/or estradiol concentrations in overconditioned cows with higher fat deposit before of ovarian cysts had occurred. |
