[Morphological changes in the placenta and in fetuses in cows with hypovitaminosis A].

Studied were morphologically 12 aborted fetuses of cows, 12 placentas of cows that miscarried, 6 placentas of cows with normal birth but with certain lesions, and 6 uteri of cows that miscarried, originating from various regions of the country. No organisms were found in both the placentas and fetuses. Carotenes in cows that miscarried gave the following values: 0.123 mg%, 0.287 mg%, 0.342 mg%, 0.684 mg%, 0.160 mg%, 0.168 mg%, 0.231 mg%, 0.430 mg%, and 0.484 mg%. Six grams of liver tissue of one of the slaughtered cows contained as many as 36 UI of vita. A. Gross investigations of the placentas revealed gray-whitish to gray-yellowish, round or oblong bulgings of 1-2 cm length. Histologically, hyperplasia and metaplasia of the surface epithelium were established, which from a monolayer one changed through metaplasia into a multilayer, flat, and cornificating one. In the lung, tongue, intestines, and vesical bladder of the fetus as well as in the endometrium of the cows that miscarried there were hyperplasia and metaplasia of the epithelium.