Genomic and Behavioral Effects of the Neonicotinoid Imidacloprid in Birds Exposed Through Pesticide-Coated Seeds

The Science: To better understand toxicity mechanisms in birds, the molecular and cellular consequences of exposure to imidacloprid-treated seeds are being investigated in Japanese quail, a granivorous species often used in ecotoxicology studies as a surrogate for ground feeding birds. Because neonicotinoid pesticides are neurotoxins, they affect elements of stress response and locomotion in vertebrates. Take-off flight and escape ability of exposed quail are being studied to identify potential impacts of imidacloprid on behaviors critical for survival. Genomic analysis will identify whether nAChRs expression is altered in brains of exposed birds and which nicotinic receptor subtype is responsible for mediating any observed behavioral effects. Gene expression profiling (transcriptome analysis) is examining changes in metabolism and immune pathways.

The Future: Sublethal effects of pesticides in the field may be difficult to understand or evaluate accurately without information garnered from controlled studies. The data from this study are important for understanding how neonicotinoid use affects seed eating birds and for determining their potential contribution to declining health of various bird species. Identification of responses and mechanisms of action will facilitate characterization by managers of the risk to birds and other terrestrial wildlife from imidacloprid exposure.