VARIATIONS IN TERATOGENIC RESPONSE TO HYPERVITAMINOSIS A IN 3 STRAINS OF ALBINO RAT

Groups of Sprague-Dawley, Charles River and Wistar rats received daily oral doses of 0, 50,000 or 75,000 IU vitamin A on days 6-15 of pregnancy. The percentage incidences of malformed foetuses for these three strains were 0·8, 0·9 and 0% for the control group, 10·2, 8·5 and 4·1 % for the group receiving the lower dose of vitamin A and 100, 34·2 and 22·2 % for the higher vitamin A group. Strain differences were seen not only in the overall incidence of malformations but also in the pattern of abnormalities in the offspring. The most common abnormalities were cleft palate, anophthalmia, exencephaly, meningocele and hydronephrosis. No skeletal deformities were induced by excessive vitamin A intake. © 1969 Pergamon Press Limited.