Feeding vitaminized peanut butter to rats to confirm chemical assays of vitamin A

Abstract

Positive results were obtained when vitaminized peanut butter was fed in small doses of 4.2 and 8.4 I.U's. of vitamin A per rat daily. Body weight increases served as criteria. For the same peanut butter, on chemical tests an average value of 69 I.U's. of vitamin A per gram was found at the initial stages of the biological tests. The doses were calculated on the chemical findings and on this basis doses of 2.1 I.U's were too small, whilst doses of 4.2 I.U. were adequate; and doses of 8.4 also allowed a small storage in the liver within 21 days of feeding. The above findings support the views of Goss and Guilbert (1939) who advocated a minimum level of vitamin daily of 18-22 I.U. per Kgm. weight in rats, which, calculated on the average weight of the rats in this experiment is equivalent to 2.5-3.9 I.U. vitamin A per dose per rat daily.