Effect of Raw Soybeans and of Soybean Oil on Plasma Carotene and on Vitamin A as Measured by Activated Glycerol Dichlorohydrin

Abstract

In a trial using paired Holstein-Friesian cows it was found that feeding raw soybeans in amts. of 9 pounds daily per lactating cow caused the blood plasma concns. of carotene in these cows to be markedly different and lower than those concns. of carotene in cows fed the control ration containing no soybean products. These differences tended to become constant after about 7-9 weeks of feeding the beans. Measurable differences occurred between the blood plasma carotene concns. of cows fed soybean oil (1.7 lb. daily per cow) and the controls with the cows receiving the soybean oil having the lesser concn. These differences were not as large as those caused by raw soybeans. The differences in the blood plasma vitamin A concn. among the cows fed the control, raw soybeans, and soybean oil rations were small and showed no particular trends. Activated glycerol dichlorohydrin proved to be satisfactory for the detn. of vitamin A in bovine blood.