Pesticide Resistance in Cattle Lice

No chemical resistance has been found in cattle lice in Australia. Resistance to both synthetic pyrethroids (SPs) and Macrocyclic Lactones (MLs) has been confirmed overseas.

Although resistance has been suspected in Australia in a number of instances, this has not been confirmed by testing.

Where frequent treatments for lice control are applied it is good practice to rotate intermittently between chemical groups to reduce the likelihood of selecting for resistance on your property.