Vitamin B 2 nutritional status of the lactating rat and her litter as a function of dietary riboflavin supplement
Leclerc, J.
International Journal for Vitamin and Nutrition Research. Internationale Zeitschrift für Vitamin- und Ernahrungsforschung. Journal International de Vitaminologie et de Nutrition 49(3): 276-285
1979
ISSN/ISBN: 0300-9831 PMID: 575114 Document Number: 144439
Five groups of female rats which had given birth to litters of 8 young (or litters adjusted to 8 young) were fed diets containing 1, 2, 4, 8 or 16 mg/kg of riboflavine, respectively. Eighteen days after littering the total riboflavine content, and in some cases the coenzymatic forms of the vitamin were measured in female tissues (plasma, liver, carcass) or in those of the young (liver, carcass). The total riboflavine content in the stomach of the young was measured 3, 7 and 14 days after birth. In the females there was a linear relationship between the riboflavine content in the tissues and the log-concentration of the vitamin in the diet when the latter did not exceed 8 mg/kg. Beyond this value the tissue vitamin content did not increase further. In the plasma, the FMN + FR forms were predominant except at low dietary vitamin supplies whereas in the liver it was the FAD form which mainly prevailed, particularly at lowest dietary vitamin levels. The gastric vitamin content (milk) in the young gradually increased as the dietary vitamin supply increased. In the young the organ riboflavine contents markedly increased when the dietary supply rose from 1 to 2 mg/kg; from 2 to 4 mg/kg it went up more slowly and finally reached a plateau when the dietary supply was higher than 4 mg/kg. As in the mothers, the FAD form predominated in the liver, particularly at lowest dietary vitamin levels. The riboflavine fixation in the offspring tissues apparently occurs prior to the fixation in the lactating mother except if the diet is very poor in riboflavine. The priority would be proved by the fast increase of the milk content in riboflavine when the vitamin dietary supply rises.