For the accomplishment of this research, twenty Nelore female fetuses in different phases of gestation were collected. The uterine horns and oviducts were dissected, measured and fragments were fixed in 4.00% tamponed paraformaldeid, processed and enclosed in paraplastic. The sections of 5mm were stained with hematoxilin and eosin, Masson's trichrome (to colagens fibers), Verhoeff (to elastic fibers) and with reticulin (to reticular fibers). The results showed that there is no significative difference among the right and left sides for the uterine horns and oviducts, but there is correlation among the measured organs in function of the age of the fetuses, or either, the growth of uterine horns and oviducts follow the fetal growth. The covering epithelium of the uterus does not present morphologic variations during the analyzed period. From 23 weeks of gestation, the mucous layer presents evolution in the development of the projections and there is no appearance of endometrial glands in the uterine wall in the analyzed period. The muscular layer presents only the developed internal circular sublayer up to 23 weeks of gestation and from 24 weeks of gestation there is presence of two sublayers. The serous layer is typical and it does not show variability in the gestation. The oviducts presents growth differences, mainly to the development of the folds that from 23 weeks of gestation they had become higher and ramified, however without appearance of tertiary folds. In the fetal development, the epithelium cilium becomes bigger. Up to 32 weeks of gestation, the muscular layer of oviducts presents the internal circular sublayer. The serous layer and mesosalpinge are typical and they do not present variations. The more characteristics variations occurred from 23 weeks of gestation.
Morphology; Uterus; Oviducts; Fetuses; Bovine
