Postpubertal changes in the histomorphometric characteristics of the uterus of the indigenous West African pig.

The epithelial height and myometrial and endometrial characteristics of the fundus, corpus and neck regions of the uteri of 28 virgin West African indigenous gilts in four age groups (6-8, 10-12, 16-18 and 20-22 months) were histometrically evaluated. Though regionally stable, the height of luminal epithelial cells was, respectively, reduced and enhanced in the fundus and neck regions by 10-12 months. The myometrium was thinner in the fundus and was severely reduced in the corpus region in gilts aged 16-18 months. Contrarily, the endometrium was regionally stable in thickness but underwent some thickening in the corpus of 16 to 18-month-old gilts. The respective occurrence of muscular and glandular tissues in the myometrium and endometrium was regionally influenced while older gilts had more circular muscles than the others. Generally, over 70% of the glands and 60% of the muscles were complex glands and longitudinal muscles, respectively. Results depict the nonuniform growth rates of different uterine tissues in the different regions and suggest that the improvement in the litter-carrying capacity of the uterus in these pigs continues well after puberty.