Diphacinone and coumatetralyl persistence in deer and implications for wildlife management

Abstract

Because of the concerns regarding wildlife contamination following the field use of anticoagulants the hepatic persistence of diphacinone and coumatetralyl has been compared in deer. Initial coumatetralyl concentrations in liver following oral dosing with 8.25 mg/kg coumatetralyl were similar on day 1 to those achieved by administration of diphacinone at 1.5 mg/kg. Coumatetralyl was more slowly eliminated (t½ 14 days) than diphacinone (t½ 6 days) and residues were still present in liver tissue after 50 days versus 12 days for diphacinone. Bioaccumulation on repeated field use is unlikely.