Strips with oxalic acid and glycerine: is it a reliable way of varroa treatment?
|Year of publication||2022|
|MU Faculty or unit|
|Description||Varroa mites (Varroa destructor) are the most significant cause of honey bee colony losses worldwide. In affected countries, beekeepers have developed strategies for the prevention and treatment of Varroa-infested colonies. Those strategies are based on regular monitoring of Varroa infestation and the application of biotechnological strategies or chemical products. The portfolio of chemical-based treatment is highly variable in each country according to local law and veterinary rules. Oxalic acid is a relatively cheap and available organic acid and is one of the many active substances present in many products used for Varroa treatment. It has been used for decades now in a form of trickling or sublimation. Those application strategies were successfully implemented by many beekeepers. The application of oxalic acid requires the exact timing within a beekeeping season and the absence of sealed brood is necessary to reach maximum therapeutic effect. If the oxalic acid-based products are applied properly, the efficacy is around 95 %. Trickling and sublimation act as a “flash” treatment with limited long-term activity on colonies, especially in the summer season (Central Europe). Recently, a new formulation of a long-term application of oxalic acid was developed. Many beekeepers started experimenting with cellulose strips impregnated with a solution of oxalic acid and glycerine. The results reported by amateur scientists – beekeepers are mostly based on the statement “I am satisfied with the treatment”. However, the data from the field on efficacy and side effects are vague, thus we decided to set up an experiment to measure the efficacy and possible side effects of this application on the honey bee organism. The experiment was performed in Czechia on 4 groups of colonies: no treatment, oxalic acid trickling, oxalic acid-glycerol strips, and flumethrin (Gabon). We measured the efficacy of the treatment and several physiological parameters related to oxidative damage, markers of longevity, immunity, and the digestive system. Our results brought a solid-based knowledge for further optimization of oxalic acid-glycerine strips in beekeeping practice. This research was funded by The Ministry of Agriculture of the Czech Republic grant QK1910286.|