Thinking twice before dosing lambs

This time of year, many sheep farmers are thinking about the best time to dose lambs for stomach worms. However, with growing concerns over wormer resistance, Enda O’Hart, Organic Advisor, advises taking a strategic approach.

With the increased incidence of wormer resistance on farms, it is advisable for farmers to begin taking dung samples, carrying out faecal egg counts (FEC), and analysing the results to determine whether treatment is justified.

The use of faecal egg counts is a pivotal strategy in reducing wormer dependence on sheep farms, offering a sustainable approach to managing gastrointestinal nematode infections. This method involves analysing the number of worm eggs present in sheep faeces, providing a direct measure of the worm burden within the flock. By utilising FEC, farmers can make informed decisions about when and which animals require treatment, thereby minimising unnecessary drenching.

One of the primary benefits of FEC is its ability to guide the timing of anthelmintic treatments. More than a quarter of participants in the Sheep Technology Adoption Programme (STAP) had pre-treatment faecal egg counts below 200 eggs per gram, indicating low levels of gut parasitism. This suggests that many treatments were unnecessary, highlighting the importance of FEC in preventing the overuse of wormers. By treating only when needed, farmers can reduce the selection pressure for anthelmintic resistance, a growing concern in sheep farming.

Moreover, FEC can be used to assess the efficacy of anthelmintic treatments. By comparing egg counts before and after treatment, farmers can determine whether the wormer is effective or if resistance is present. This is crucial for maintaining the effectiveness of available treatments and ensuring the health and productivity of the flock.

In addition to reducing wormer use, FEC contributes to improved pasture management. By identifying and addressing high worm burdens, farmers can implement grazing strategies that lower pasture infectivity, further reducing the need for chemical interventions.

In conclusion, faecal egg counts are an invaluable tool in sustainable sheep farming. They enable targeted treatment, reduce the risk of resistance, and support effective pasture management, ultimately leading to healthier flocks and more sustainable farming practices.