Bayvarol
Behandlungsmittel
Bayvarol consists of plastic strips, each containing 3.6 milligrams of flumethrin.
Bayvarol consists of plastic strips, each containing 3.6 milligrams of flumethrin. The strips are hung in the comb spaces of the brood nest. The bees walk over them, pick up the active substance on their surface, and distribute it through the whole colony via contact with each other.
Flumethrin is a synthetic pyrethroid and acts as a contact poison on the mite's nervous system. It keeps sodium channels permanently open, leading to overexcitation, coordination disorders, paralysis, and eventually death. The active substance does not reach the capped brood cells. Mites sitting there are only caught after the bee hatches, which is why a sufficiently long application is necessary.
For normally developed production colonies in two boxes, four strips are provided; for weak colonies, nucleus colonies, and young colonies where less than half the combs are occupied, two strips. Treatment duration is at least four and at most six weeks. Treatment is carried out after the last honey harvest in summer. From November or December until the following summer, no strips may remain in the colonies.
This is precisely where the most common and consequential application error lies: strips that remain in the colony too long, or even over winter, expose the mites to a persistent, sub-lethal dose of active substance. This is the classic path by which resistance develops. Resistance of the Varroa mite to pyrethroids is known in Germany and regionally widespread, with a mutation at the target receptor in the sodium channel as the most common mechanism. The active substance should therefore not be used in consecutive years. Treatment with Bayvarol alone is generally not sufficient; a final mite treatment during the broodless period remains necessary.
Bayvarol is approved as a veterinary medicinal product in Germany and subject to pharmacy sale, but not prescription-only. The withdrawal period for honey is zero days, provided treatment was not carried out before or during the nectar flow. In the following nectar flow, only sieved and skimmed honey without comb fragments may be harvested. It should be considered that flumethrin is fat-soluble and leaves persistent residues in beeswax. The application must be documented in the Colony Register. When handling the strips, gloves should be worn; used strips are hazardous waste.
Quellen (4)
- Bayvarol 3,6 mg, EU Union Product Database, Zulassung Deutschland (Nr. 26288.00.00)
- Die Honigmacher (Landwirtschaftskammer NRW): Bayvarol
- Emmerich, I.: Zugelassene Arzneimittel für Honigbienen in Deutschland, Berliner und Münchener Tierärztliche Wochenschrift 2018
- LLH Bieneninstitut Kirchhain: Infoblatt Varroazide