Determination of the efficacy of thymol, Artemisia absinthium oil and nanoparticle ozone in the treatment of Nosema ceranae in adult honey bees

The therapeutic efficacy of various concentrations and combinations of thymol, Artemisia absinthium oil and nanoparticle ozone against Nosemosis caused by Nosema ceranae in honey bees was studied. Two-hundred colonies were examined for N. ceranae positivity and negativity under light microscopy; 119 colonies were positive and 81 colonies were negative for Nosemosis. The study evaluated the therapeutic efficacy of 17 different combinations against N. ceranae. Nine of the 17 combinations were applied by spray to frames and eight were applied orally (combinations added to the sugar syrup reservoir) to the hives. Each of the 17 combinations was prepared in 1,000 ml from (2%, 3% and 5%) of thymol and (2% and 3%) A. absinthium oil, and 1,000, 2,000, 4,000, and 8,000 ppm concentrations of nanoparticle ozone. N. ceranae spore counts before and after the treatment were counted on Neubauer thoma slides by the digestion method, and the efficacy of the combinations was determined by the percent reduction test. In spray form, 200 ml 2,000 ppm nanoparticle ozone + 100 ml 3% thymol + 700 ml sugar syrup (efficacy-89.47%) (Group 5) and in oral form, 250 ml 2% thymol + 200 ml 2% A. absinthium oil + 500 ml sugar syrup (efficacy-85.95%) (Group 16), were found to be more effective. In conclusion, the combination of thymol and nanoparticle ozone in spray form was more effective than other combinations in this study.