Induction of abnormal behaviours in mice after in utero and early postnatal exposure to imidacloprid

Imidacloprid (IMD), a neonicotinoid insecticide, is the most widely used insecticide on the planet. The purpose of this study was to examine the behavioural and biochemical effects of chronic in utero and early postnatal IMD exposure. Our treatment regimen entailed chronic exposure whereby pregnant mice were infused with 0.5 mg/kg/day of IMD via a subcutaneous osmotic mini-pump from gestational day 3 to postnatal day 21. Beginning on postnatal day 42, the offspring were studied in a series of behavioural tests assessing locomotor activity, anxiety, social dominance and aggression, sensorimotor gating, and depression, while postmortem biochemical analyses included tests that observed sperm abnormalities, immune response abnormalities, and abnormalities in whole blood composition. A decrease in body weight, increased motor activity, enhanced social dominance, decreased depressive-like behaviours, and a decrease in visible social aggression was observed, demonstrating the induction of abnormal behaviours in mice after in utero and early postnatal exposure to IMD.
Source:
Andrew Patrick Burke (2016) Thesis submitted in conformity with the requirements for the degree of Master of Science. Graduate Department of Pharmaceutical Sciences, University of Toronto.