Involution of the post partum uterus of the Boer goat.

The microscopic uterine involutionary changes were studied in Boer goats (n = 16) from 2 h to 34 d post partum. The endometrial epithelium showed a linear decrease in thickness with time post partum. A highly significant negative correlation (r = -0.94; P less than 0.01) was found between the endometrial epithelium layer thickness and time post partum. The lamina propria layer showed a rapid decrease during the first 20 d post partum and then tended to level out. According to the statistical model (y = AeBt + Ct2) fitted by 25.2 d post partum, the thickness of the lamina propria layer was static. The myometrium decreased significantly (P less than 0.01) in thickness from Day 24 to Day 34 post partum. The thickness of the serosa followed a linear-type decrease during the observation period, while in the glandular epithelium the decrease was rapid during the first 12 d following parturition. The uterine glands reached normal size 22.1 d after parturition. The involution process of the uterus was microscopically complete by Day 28 post partum, the main indicator being the degree of recovery of the endometrial epithelium over the caruncular areas.