Bait markers are indispensable for ecological research but in small mammals,most markers are invasive,expensive and do not enable quantitative analyses of consumption.Ethyl-iophenoxic acid(Et-IPA)is a non-toxic,quanti...Bait markers are indispensable for ecological research but in small mammals,most markers are invasive,expensive and do not enable quantitative analyses of consumption.Ethyl-iophenoxic acid(Et-IPA)is a non-toxic,quantitative bait marker,which has been used for studying bait uptake in several carnivores and ungulates.We developed a bait with Et-IPA,assessed its palatability to common voles(Microtus arvalis),and determined the dose-residue-relation for this important agricultural pest rodent species.Et-IPA concentrations of 40 to 1280μg Et-IPA per g bait were applied to wheat using sunflower oil or polyethylene glycol 300 as potential carriers.In a laboratory study,common voles were offered the bait and blood samples were collected 1,7,and 14 days after consumption.The samples were analyzed with LC-ESI-MS/MS for blood residues of Et-IPA.Sunflower-oil was the most suitable bait carrier.Et-IPA seemed to be palatable to common voles at all test concentrations.Dose-dependent residues could be detected in blood samples in a dose-dependent manner and up to 14 days after uptake enabling generation of a calibration curve of the dose-residue relationship.Et-IPA was present in common vole blood for at least 14 days,but there was dissipation by 33–37%depending on dose.Et-IPA meets many criteria for an“ideal”quantitative bait marker for use in futurefield studies on common voles and possibly other small mammal species.展开更多
基金funded by the German Federal Ministry of Food and Agriculture due to a parliamentary resolution within the federal program“Organic farming and other forms of sustainable agriculture”(file#2815NA113)All animal experimentation was conducted in accordance with EU and federal legislation(file#No.81-02.04.2019.A246).
文摘Bait markers are indispensable for ecological research but in small mammals,most markers are invasive,expensive and do not enable quantitative analyses of consumption.Ethyl-iophenoxic acid(Et-IPA)is a non-toxic,quantitative bait marker,which has been used for studying bait uptake in several carnivores and ungulates.We developed a bait with Et-IPA,assessed its palatability to common voles(Microtus arvalis),and determined the dose-residue-relation for this important agricultural pest rodent species.Et-IPA concentrations of 40 to 1280μg Et-IPA per g bait were applied to wheat using sunflower oil or polyethylene glycol 300 as potential carriers.In a laboratory study,common voles were offered the bait and blood samples were collected 1,7,and 14 days after consumption.The samples were analyzed with LC-ESI-MS/MS for blood residues of Et-IPA.Sunflower-oil was the most suitable bait carrier.Et-IPA seemed to be palatable to common voles at all test concentrations.Dose-dependent residues could be detected in blood samples in a dose-dependent manner and up to 14 days after uptake enabling generation of a calibration curve of the dose-residue relationship.Et-IPA was present in common vole blood for at least 14 days,but there was dissipation by 33–37%depending on dose.Et-IPA meets many criteria for an“ideal”quantitative bait marker for use in futurefield studies on common voles and possibly other small mammal species.
