Coopers Animal Health has just released their latest lice and worm control product – Coopers Maverick. It contains 6g/L Abamectin, a macrocyclic lactone (ML), and controls both sheep lice and susceptible worms in a single pour-on application. Maverick is a water-based, off-shears pour-on registered for the control of sheep body lice (Bovicola Ovis) and the treatment and control of Abamectin sensitive strains of worms in sheep.

Maverick must be applied within 24 hours of shearing, at a dose rate of 10ml/10kg liveweight, in two adjacent bands, either side of the backline, from poll-to-tail on each sheep.

Coopers Animal Health encourages sheep producers to conduct regular worm egg counts (WEC’s) to monitor worm populations and the need to drench and also a drench resistance test (WECRT) every two to three years to monitor drench effectiveness on their property.

Knowing the drench resistance status on a property is important when considering a rotational drench program, which should include both single active drenches and combination drenches.

Where does it fit in a management program?

Firstly, it provides a new active for lice control. It is unlikely that any lice populations are resistant to Abamectin.

The prevalence of Abamectin resistance in sheep worms in Australia ranges from low (<5% of properties) to high (>60% of farms) depending on the region and the worm species, but it is increasing. This means that, as with all drenches, you should have a drench resistance test confirming that abamectin is fully effective on your property before you use it as a worm control product.

The best fit for Maverick is obviously where there is a lice infestation in conjunction with a susceptible worm population at shearing time. 

In addition, it is highly recommended that an oral drench of a different drench group is given concurrently so that the animals effectively receive a combination drench against worms. This is particularly important in areas with barber's pole worm, as there is a significant level of drench resistance to abamectin. Combination drenches are one of the cornerstones to slowing the development of drench resistance.

Note that worms don't discriminate on whether the product was given orally, by injection or by a pour-on—no matter the administration route, they can all cause the development of drench resistance.

To use it for lice only or for worms only is likely to be expensive and not take advantage of the full potential of the product. Using any product as a “just in case” treatment is foolish and wasteful of time and money.

In summary, a useful, innovative product that will have application in those sheep districts where lice and worms are concurrent problems.