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Control of Coagulation: A Gift of Canadian Agriculture
Clinical and Investigative Medicine (2006)
  • Vivian McAlister, The University of Western Ontario

Vitamin K, heparin and their antagonists remain the basis of coagulation therapies today, more than half a century after their discovery. Failure of blood clotting in chicks that were fed a fat-depleted diet was observed by William McFarlane, William Graham Jr. and Frederick Richardson of the Ontario Agricultural College; it led to the search that yielded vitamin K. Investigation of hemorrhagic disease in cattle by Francis Schofield of the Ontario Veterinary College found an anti-thrombin substance in spoiled clover which was later characterized as dicoumarol, a vitamin K antagonist, and led to the development of warfarin. In Toronto, a systematic approach lead by Charles Best resulted in the world's first plentiful supply of purified heparin. Clinical usefulness of heparin in thrombosis, embolism, cardiovascular surgery, dialysis and transplantation was demonstrated first by Gordon Murray and Louis Jaques. The roles and the careers of Canadian coagulation research pioneers are briefly presented in this review, which shows how clinical medicine benefited by the systematic development of agricultural science in Guelph, Ontario.

  • Agriculture,
  • Animals,
  • Anticoagulants,
  • Canada,
  • Coagulants,
  • Heparin,
  • History,
  • 20th Century,
  • Humans,
  • Thrombosis,
  • Vitamin K,
  • Warfarin
Publication Date
December, 2006
Citation Information
Vivian McAlister. "Control of Coagulation: A Gift of Canadian Agriculture" Clinical and Investigative Medicine Vol. 29 Iss. 6 (2006)
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