Resistance testing and the effectiveness of difenacoum against Norway rats ( <i>Rattus norvegicus</i> ) in a tyrosine139cysteine focus of anticoagulant resistance, Westphalia, Germany

Abstract

The study showed that, although the RF for difenacoum among rats carrying the Y139C SNP was apparently low, an acceptable level of control of resistant Norway rat infestations was not achieved using difenacoum. Continued use of anticoagulants against rats that are resistant to them will exacerbate resistance problems in terms of both increased severity and prevalence. These conclusions are likely to apply elsewhere in Europe where the Y139C SNP occurs.