In 1941 Link and his associates discovered that the hemorrhagic, "sweet clover disease" of cattle was due to inhibition of prothrombin formation by the hydroxycoumarin compounds present in spoiled sweet clover. Link's discovery not only resulted in a better understanding of this disease but led, first, to the use of anticoagulants to prevent intravascular clotting in man and, now, to the development of a powerful weapon for rodent control.
In the past, the efficacy of rodenticides depended on the ingestion by the rodent victim of a single dose of lethal strength. The disadvantage of these preparations lay in the hazard they presented to domestic animals and man and in the fact that rats surviving a sublethal dose tended to develop a bait shyness which soon reduced the efficiency of the preparation in eradicating rat colonies. Efforts to develop more toxic substances of bland taste or to discover materials either to
ANTICOAGULANTS AS RODENTICIDES. JAMA. 1951;145(11):824-825. doi:10.1001/jama.1951.02920290050012