Date Time Research prompts increase to recommended mouse bait rates A new research investment by the Grains Research and Development Corporation (GRDC), led by Australia’s national science agency, CSIRO, has enabled increases to zinc phosphide (ZnP) mouse baits that will help grain growers battling above-average mouse numbers. Photo CSIRO A new research investment by the Grains Research and Development Corporation (GRDC), led by Australia’s national science agency, CSIRO, has enabled evidence-based increases to zinc phosphide (ZnP) mouse baits that will help grain growers battling above-average mouse numbers in eastern Australia. ZnP-coated wheat bait is the only registered in-crop rodenticide for the management of mice damage in broad-scale agriculture in Australia. The new Australian Pesticides and Veterinary Authority (APVMA) emergency use permit increases the concentration of zinc phosphide active per wheat grain from 25 mg/kilogram to 50 mg/kg.