In vitro efficacy of amitraz and cypermethrin on Boophilus microplus from dairy farms in Lara State, Venezuela.

In Venezuela, the acaricides, amitraz and cypermethrin, are widely used to control tick infestations in cattle infested with Boophilus microplus. This work aims to determine the in vitro efficacy of amitraz and cypermethrin through the adult immersion test. A sample of 480 engorged females was collected from four dairy farms (180 ticks/farm) and divided in groups of 10 ticks averaging 220 mg/tick.