Dicoumarol studies with farm livestock
Linton, John Herbert
The causal relationship between spoiled sweet clover and a hemorrhagic condition in cattle was demonstrated by Schofield (31) in 1922. Since that time it has been found that the direct agent is dicoumarol, an anticoagulant causing hypoprothrombinemia and which is formed from coumarin during the spoilage process. All common varieties of sweet clover contain substantial amounts of coumarin, but recently a new coumarin variety "Cumino" has been developed in Canada. The low coumarin character, however, is determined by a single recessive gene, consequently the variety may become rapidly contaminated because of cross-pollination with nearby stands or volunteer roadside sweet clover plants. Since contamination seems inevitable, the problem arises of establishing the relationship between the degree of contamination of low coumarin varieties and the potential risk involved in their use as feeds. Such information might be of value in establishing standards of varietal purity. The objectives of this study included comparisons of the responses by several classes of farm livestock to dicoumarol ingestion, attempts to deterrnine the levels of dicoumarol intake necessary to create blood coagulation disorders sufficient to endanger life of health, and the effects of vitamin K3 administered as a dietary supplement as a potential counteractant to dicoumarol.