Chronic Cadmium Exposure Induces Impaired Olfactory Learning and Altered Brain Gene Expression in Honey Bees (Apis mellifera).

However, the honey bees exhibited a reduction in consuming the sucrose containing not less than 1 ug/mL of CdCl SB 2 sb ; although non-significant, there exists the possibility that sucrose containing more than 1 ug/mL of Cd may affect honey bee sucrose responsiveness that is essential for olfactory learning in honey bees [[38]]. We, therefore, investigated whether honey bees exposed to chronic Cd exhibited altered olfactory learning, and we further compared the patterns of brain gene expression between cadmium-exposed bees and control bees using RNA-seq analysis. Our studies showed that the head weight was significantly lower in cadmium-exposed bees when compared to controls, suggesting chronic Cd exposure may have adverse effects on the total protein content of the mandibular and hypopharyngeal glands in the heads of adult honey bees, thus resulting in a decrease in head weight in Cd-exposed bees. [Extracted from the article]