ELANCO is encouraging animal health advisors to have the conversation about the need to adopt effective rotation programs to maintain the efficacy of all available sheep lousicides.
The currently available pour-on lousicide products belong to four chemical classes with different modes of action: neonicotinoids (e.g. imidacloprid, thiacloprid), spinosyns (e.g. spinosad), macrocyclic lactones (MLs) (e.g. abamectin) and organophosphates (e.g. temephos, diazinon).
Elanco Australasia Senior Brand Manager, Dr Kathryn Humphries, says resistance can develop to any chemical if it is used continuously.
“Australian sheep and wool producers have relied upon neonicotinoids and spinosad for the last decade as their ‘go-to’ pour-on lousicides,” Dr Humphries says.
“While there is no known resistance of lice to either of these modes of action, it’s important that we keep it that way.
“Now is the time to establish a rotation regime with products of different classes to protect these molecules from the development of potential resistance.
“The lousicide rotation wheel provided is an easy visual representation to help guide conversations on product selection,” advises Dr Humphries.
“The first question to ask is what product did you use to treat lice last time? As the aim is not to apply lice treatments with the same mode of action consecutively, this will help with the decision on the most appropriate product class to select.”
Another question is to ask in spring is about the choice of chemicals to be used for blowfly strike prevention. It is important not to apply products with the same mode of action to control lice and blowflies in the same season as there is a risk lice will receive sublethal doses of chemical when it is applied for fly control.
“An important consideration if selecting products containing abamectin is that these products treats both lice and worms. Even though the product is applied as a pour on backline to kill lice, it is also absorbed into the bloodstream and kills susceptible roundworms. Precautions need to be taken to minimise the development of drench resistance.”
As with all products, correct application is important to ensure optimal outcomes. “Remind producers to always read and follow the label directions. Encourage your producers to visit Liceboss.com.au for industry recommendations on effective lice management.” suggests Dr Humphries.
‘Product stewardship is everyone’s responsibility and spring is the perfect time to be initiating these conversations.”
For more information or to talk to one of the Elanco technical or sales teams for advice on lice solutions for the upcoming 2021 spring shearing season, please contact Elanco on 1800 226 324 or ANZCustomerAdviceLine@elancoah.com