Investigations on the effect of maternal dietary riboflavin supplementation during gravidity and lactation on riboflavin concentrations in blood, liver, and total body of rat offspring

The present study investigated the effect of various maternal dietary riboflavin supplementations during gravidity and lactation on riboflavin concentrations in blood, liver, and total body of their offspring. Therefore, two experiments with a total of 154 female rats were conducted. In the first experiment the animals received a semisynthetic diet (basal riboflavin concentration of 0.9 mg/kg diet) with various riboflavin supplementations during lactation (0, 2, 4, 6, 8, 10, 12, 40, 400, 4000 mg riboflavin/kg diet). In the second experiment, during gravidity, the rats were fed supplements of 1 or 20 mg riboflavin/kg diet. After parturition each group was divided into three subgroups that received 1, 5 or 20 mg riboflavin/kg with their feed during the following lactation. Both investigations continued until the 14th day of the lactation period just before the pups would start to eat the diets. The total body weights of the offspring in the first experiment only showed an effect of the riboflavin supplementation during lactation in the riboflavin-deficient group (supplementation of 0 mg/kg diet). Regarding the second experiment, the total body and liver weights of the offspring on the 14th day of lactation were not significantly influenced by the various maternal riboflavin supplements during gravidity and lactation. The data of the first experiment clearly show that there exists a slight dose-response relationship between the maternal dietary riboflavin supplementation during lactation and the riboflavin concentration in the blood and total body of the offspring. However, a riboflavin supplementation over 8 mg/kg diet led to a saturation of the riboflavin concentration in the body. Also, a dietary supplementation above 2 mg riboflavin/kg diet had no influence on the liver riboflavin concentration. The second investigation showed that the riboflavin concentration in all samples was influenced predominantly by the maternal riboflavin supply during lactation. The riboflavin supply during gravidity had no or only a very slight effect on the riboflavin concentrations in blood, liver, and total body of the offspring. In conclusion, these results indicate the necessity of a sufficient maternal dietary riboflavin supply (8-9 mg/kg diet) during lactation in regard to the health of their offspring and that a high riboflavin supply during gravidity cannot compensate for a deficient supply during lactation.