Factors affecting the uterine weight of ewes ovariectomized for bioassay procedures

Abstract

The pattern and rate of regression of the ovine uterus following ovariectomy were examined and discussed in relation to the use of such animals in oestrogen bioassay. Uterine weight decreased linearly between 2 and 6 weeks after ovariectomy, and did not reach an asymptote in this time; the rate of decrease was 1.7 g/week (c. 6 %of the uterine weight 2 weeks after ovariectomy). The concomitant rate of dry matter loss was 0.25 g/week. The stage of the oestrous cycle at which ovariectomy was performed had no effect on uterine weights between 2 and 6 weeks later.