Congenital Malformations as Related to Deficiencies of Riboflavin and Vitamin B12, Source of Protein, Calcium to Phosphorus Ratio and Skeletal Phosphorus Metabolism ,

Abstract

The corn-wheat gluten rachitogenic diet devised by Steen-bock and Black is deficient in vitamin B₁₂ and riboflavin, and possibly in folic acid. There was a high incidence of hydrocephalus, ocular defects and skeletal abnormalities among the offspring of dams fed this diet and the incidence of the malformations was greatly reduced by adding the known vitamins required by the rat. The addition of these vitamins to a diet in which the dietary protein was of soybean origin gave nearly complete protection. The omission of vitamin B₁₂ resulted in hydrocephalus, eye defects and an increased incidence of bone defects. Omission of riboflavin had no effect on the incidence of hydrocephalus or eye defects but increased skeletal abnormalities. The omission of both gave a still higher incidence of skeletal abnormalities. A high Ca:P ratio also increased skeletal defects. The alkaline phosphatase activity in the tibiae of riboflavin- and vitamin B₁₂-deficient newborn was lower than normal. The rate of phosphorus deposition in the tibiae of vitamin B₁₂-depleted offspring as measured by specific activities after P³² administration was also decreased. The latter facts give an indication of the cause of the high incidence of skeletal abnormalities in cases of riboflavin and of vitamin B₁₂ deficiencies.