Seed Meals from and Control Artificial Infections in .

is a widespread parasite responsible for nosemosis Type C in honey bees, reducing colony survival. The antibiotic fumagillin is the only commercial treatment available, but concerns are emerging about its persistence, safety, and pathogen resistance. The use of natural substances from Brassicaceae defatted seed meals (DSMs) with known antimicrobial and antioxidant properties was explored. Artificially infected bees were fed for 8 days with candies enriched with two concentrations, 2% and 4%, of two DSMs from and , containing a known amount of different glucosinolates (GSLs). The food palatability, GSL intake, bee survival, and treatment effects on spore counts were evaluated. Food consumption was higher for the two 2% DSM patties, for both and , but the GSL intake did not increase by increasing DSM to 4%, due to the resulting lower palatability. The 2% patty decreased the bee mortality, while the higher concentration had a toxic effect. The control was significant for all formulates with respect to the untreated control (312,192.6 +/- 14,443.4 s.e.), and was higher for 4% nigra (120,366.3 +/- 13,307.1 s.e.). GSL hydrolysis products, the isothiocyanates, were detected and quantified in bee gut tissues. Brassicaceae DSMs showed promising results for their nutraceutical and protective effects on bees artificially infected with spores at the laboratory level. Trials in the field should confirm these results.