Insecticidal ear tags are moulded plastic tags that are impregnated with insecticide. Insecticide is released slowly onto the surface of the tag by diffusion and the action of grooming spreads the insecticide over the animal.
Chemical actives in fly tags sold in Australia for the control of paralysis ticks are synthetic pyrethroids (SPs). The tags can aid in the control of paralysis tick on suckling beef and dairy calves for up to 42 days.
Two tags should be applied per animal (one in each ear), when tick numbers exceed acceptable levels and calves are at greatest risk.
Ear tags must be removed once the protection period on the label has expired to avoid exposing paralysis ticks and buffalo flies to sub-lethal concentrations of the chemical, which increases selection for resistance.
Tags should be applied to the animals in a similar fashion to an identification tag, between the second and third rib cartilage of the ear taking care not to penetrate the cartilage or any blood vessels. Use purpose-designed applicator pliers, and ensure the tag body is attached on the back of the ear. A new product, PYthon Insecticidal Cattle Strips, which can be attached to existing ear tag studs and doesn’t require insertion of a new tag has also recently been registered in Australia and aids in the control of paralysis tick.
All tags must be removed before cattle are sent for slaughter.