Amino-Acetonitrile Derivatives (AADs) - which are effective against roundworms, including resistant strains, and will help ensure a sustainable future for sheep farming in the UK and Ireland.
The first truly novel anthelmintic class for livestock to be launched in more than 25 years, Zolvix, with the new active ingredient monepantel, kills all key sheep gastro-intestinal nematodes (roundworms), including those resistant to the existing treatments.
The development of this new drench follows the persistent challenge from worms that have developed resistance to the three other classes of drench - white (benzimidazole or 1-BZ), yellow (levamisole or 2-LV) and clear (macrocyclic lactone or 3-ML) and combinations of these. Zolvix has a unique mode of action and so forms a fourth generation of anthelmintic, which will be known as the 4- AD, or orange drench class
The multinational pharmaceutical company Novartis Animal Health has prioritised the UK and Ireland as key launch countries for Zolvix to provide their sheep farmers with an answer to the pressing challenge of increasing anthelmintic resistance, which threatens the sustainability of sheep farming globally, as well as in the UK and the Republic of Ireland.
It sees Zolvix as an important management tool to help farmers control the resistant worm populations on their farms. It will also be needed for quarantine dosing when stock are moved on to farms and at mid-season for lambs to remove any resistant worms that have built up through the grazing season and may be adversely affecting lamb productivity.
Resistance is important to a farmer because it means drenches may stop working, and that leads to a loss of productivity. A study carried out by Novartis Animal Health in conjunction with the Hopkirk Research Institute showed that Zolvix treated sheep gained 33.5%, or 2.8 kg deadweight, more than sheep treated with a drench to which they were resistant.
Lesley Stubbings, an Independent sheep consultant and Sustainable Control of Parasites in Sheep (SCOPS) panel member, states "Resistance has become an ever increasing threat since the last new anthelmintic group was introduced to the UK market more than 25 years ago. Zolvix offers farmers a valuable opportunity to maintain good worm control and prolong the effective life of the existing products. Following the SCOPS guidelines to carefully integrate Zolvix into worm control strategies, before the other groups fail, will allow our sheep industry to reap the full benefits of this new novel group."
Novartis Animal Health Brand Manager Simon Harris points out: "Parasite resistance is a growing problem that decreases the productivity of sheep of all ages. Many veterinarians and farmers are concerned about this, with an increasing number of farmers reporting resistance to the three groups of wormers that have been available up to now, so the introduction of Zolvix is very timely."
"Because Zolvix manages worm burdens and kills nematodes (worms) resistant to other anthelmintic groups, it will improve the sustainability of other drench families and sheep production as a whole."
Mr Harris adds: "While Zolvix could be a lifeline for farmers who are already facing the challenge of wormer resistance to all three of the other groups of wormer, we are recommending that all farmers should use it in conjunction with their current wormers."
He explains: "Zolvix should be used as a quarantine dose to treat all sheep moving on to a farm, as recommended by SCOPS. This prevents the importation of all roundworms, including worms that are resistant to current classes of anthelmintic, thus preserving their effectiveness, as well as on farm sustainability and productivity."
"The other key time to use Zolvix is mid season in lambs, when they may have built up a burden of resistant worms following the use of other classes of wormer. As Zolvix has 99.9% efficacy against target worms, including resistant worms, its use removes this resistant worm burden, ensuring good productivity in the vital weaning and fattening period."
A broad spectrum drench, Zolvix can fit into any drenching programme. It has an impressive safety profile and can be used with confidence when prescribed by a veterinarian."
