Metabolism of Vitamin K and Influence on Prothrombin Time in Milk-Fed Preruminant Calves

¹ Department of Dairy Science, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster 44691

The metabolism of vitamin K was studied in 66 preruminant veal calves that were fed supplemental menadione sodium bisulfite complex or phylloquinone. Menadione sodium bisulfite complex was converted by intestinal microorganisms to menaquinone-4 and absorbed and stored in the liver as menaquinone-4. Phylloguinone was absorbed unchanged. Production of menaquinones 6, 7, 8, and 10 by intestinal microorganisms also was observed, but was not dependent upon dietary vitamin K. No difference was noted in prothrombin time among the groups. Intestinal microorganisms provide sufficient vitamin K to meet the physiological needs of calves fed milk replacers. Menaquinone-4 was the form of vitamin K used to meet the calf's requirement.

Key Words: vitamin K • menadione • prothrombin time

Submitted on October 12, 1989
Accepted on June 11, 1990