Data for: Breeding honey bees (Apis mellifera L.) for low and high Varroa destructor population growth: gene expression of bees performing grooming behavior

Background
Social organisms, including honey bees (Apis mellifera L.), have defense mechanisms to control the multiplication and transmission of parasites and pathogens within their colonies. Self-grooming, a mechanism of behavioral immunity, seems to contribute to restraining the population growth of the ectoparasitic mite Varroa destructor in honey bee colonies. Because V. destructor is the most damaging parasite of honey bees, breeding them for resistance against the mite is a high priority of the beekeeping industry. We conducted a bidirectional breeding program to select honey bee colonies with low and high varroa population growth (LVG and HVG, respectively). Having high and low lines of bees allowed the study of genetic mechanisms underlying self-grooming behavior between the extreme genotypes. Worker bees were classified into two categories: ‘light groomers’ and ‘intense groomers’. The brains of bees from the different categories (LVG-intense, LVG-light, HVG-intense, and HVG-lig..., A total of 2,496 worker bees were collected from the brood chambers of three colonies selected for LVG, and from three colonies selected for HVG at the Honey Bee Research Centre, University of Guelph (43° 32' 11.292\"N, -80° 12' 50.9898\"W; De la Mora et al., 2020). Briefly, for each colony, three frames with bees from the brood chamber were shaken into a 5 L plastic container, and a scoop of bees (from different ages) was collected and transported into the lab. The bees used for self-grooming assays were randomly selected. The bees were subjected to self-grooming assays as per Guzman-Novoa et al. (2012) with modifications by Morfin et al. (2020). For each self-grooming assay, each worker bee was placed inside a Petri dish (100 mm x 15 mm; Fisher Scientific, Mississauga, ON, Canada) covered with a perforated lid, the worker bee was left for 2 min to become used to the environment. After that, approximately 20 mg of wheat flour (Robin Hood®, Markham, ON, Canada) was put on her thorax using...,