Fluvalinate content of Apistan(R) strips during treatment and efficacy in colonies containing sealed worker brood

Over the last few years, some studies were carried out in Sardinia (Italy) on improving varroosis management in colonies containing sealed worker brood using Apistan. The fluvalinate content in plastic strips remained almost constant during the 10 weeks of treatment. No significant differences between initial (11.5 + 0.6%) and terminal (10.7 + 0.3%) fluvalinate concentration were observed, indicating that removal by the bees was very small and the active ingredient strip dosage more than sufficient to control the varroosis. Apistan application in apiary confirmed an efficacy of over 99%. Most of the mire mortality (> 97%) occurred during the first 4 weeks.