Building on earlier success, further trials of targeted selected treatment using SmartWorm® across diverse farming systems have shown that drench use can be substantially reduced without major impacts on lamb growth.
The project’s second phase – also funded by Beef + Lamb New Zealand (B+LNZ) – involved over 3,900 lambs across six farms, building on an earlier pilot involving over 1,400 lambs on three farms. Across both trials, SmartWorm® confirmed its early findings: the app can cut drench use by around half while supporting animal performance and farm profitability.
SmartWorm® uses targeted selective treatment (TST), combining animal-specific data like liveweight, age, and growth potential to decide whether each lamb needs drenching. It integrates with existing eID tag and weighing equipment and communicates with drafting systems to simplify treatment decisions.
Dr Cara Brosnahan, Principal Scientist Animal Health Research at B+LNZ, says the tool could be a game-changer for parasite control.
“SmartWorm® helps us move away from blanket drenching and gives farmers more precise, real-time recommendations. It’s a tool that supports productivity while also slowing resistance development and being able to identify those animals needing less drench.”
In the second study, SmartWorm® was put to the test across a variety of farm types and forage systems, from Hawkes Bay to Southland. Lambs were split into two groups: one group all received treatments with an effective anthelmintic monthly, and the other was treated based on SmartWorm®’s recommendations.
The results?
Across both trials, drench use was reduced by a mean of 48–49 percent, with some farms achieving over 57 percent reductions – similar to the first trial’s outcomes.
While there was no significant difference in liveweight gain between SmartWorm® and blanket-treated lambs in the first study, the second study showed a slight reduction in average daily gain in SmartWorm® groups compared to blanket-treated lambs. This trade-off was modest and expected due to allowing for refugia, and farmers reported the productivity loss was outweighed by savings in drench and labour.
“Yes, there was a small trade-off in weight gain on some farms, but the ability to reduce drench use so significantly, with minimal productivity loss, is a major step forward. This is a viable option for many commercial farms” adds Dr Brosnahan.
"It's a WIN-WIN-WIN–lower drench use, providing refugia and the opportunity to breed animals with a low drench requirement" Sarah Williams, Veterinarian, North Canterbury Vets.
SmartWorm® also proved economically beneficial. In the first study, direct savings from reduced drench use averaged $0.79 per lamb, with indirect savings of $1.43 per lamb through reduced reliance on specialist drenches to address resistance – totalling potential savings of $2.22 per lamb. After factoring in the cost of eID tags, the estimated net savings averaged $0.59 per lamb.
Initially, getting the software working with farm equipment took some setup time, but once in place, farmers reported that the system worked well, especially when supported with faecal egg count (FEC) monitoring.
The second phase also tested SmartWorm® in regions vulnerable to Haemonchus (barber’s pole worm), with cautious success. Farmers are advised to work closely with their vets when using TST strategies in these areas. SmartWorm® has recently added a feature that allows a fixed portion of the mob to be blanket-treated at each TST event, helping farmers assess predictions and manage contamination risks.
Looking ahead, the SmartWorm® app is poised to become a practical, on-farm solution for integrated parasite management. As parasite resistance continues to rise, tools like SmartWorm® offer farmers a way to reduce reliance on drenches while maintaining productivity.
“SmartWorm is a game changer and worth persevering with. I trust it and am definitely integrating it into my breeding program,” says farmer Warwick Lissaman.
“We’re only scratching the surface of what precision tools like SmartWorm® can do,” says Dr Brosnahan.