Being sure to use quarantine treatments on bought-in animals will reduce the risk of bringing wormer resistant parasites onto your farm. Planning ahead for this can bring a host of benefits, but there are a few additional prevention areas we can look at as well.

Breeding your own replacements further reduces the risk of bringing new parasites onto your farm and homebred replacement stock are more likely to have resistance to parasites found on your farm. It may be possible to breed genetically resistant livestock to high parasite burdens. Please speak with your vet for more information.

Host immunity is important. Ensuring youngstock have had the best start in life with adequate colostral transfer will help as it gives lambs the best start in life and reduces the risk of disease early in life. This can be easily monitored. Vaccination can be used to boost immunity – animals immunosuppression are more at risk of
becoming clinically diseased from high parasite burdens on pasture and other diseases.

Nutrition also plays a role in host immunity with animals on a higher plane of nutrition often performing better. Studies have shown that ewes on a high protein diet have lower FECs than those on a standard protein level.

What about their mineral/trace element status? Have they received a bolus if it is required or receiving another mineral supplementation?

Incorporating other grasses / herbs into pasture. Chicory has been shown to lead to a 40% reduction in worm burdens in sheep. Plantain may also have an effect. Other plants that have been studied include sainfoin and birdsfoot trefoil as they contain condensed tannins which disrupt the parasite lifecycle.

Longer sward length of grasses may be helpful for controlling parasite burden in your animals. Worm eggs tend to be found at the base of stalks, so if cattle or sheep are grazing longer awards, it may be possible to reduce contact with worm eggs which cause infection by digestion – although this is only relevant for herbal leys as opposed to ryegrass systems.

Try to avoid utilising the same pasture year on year for youngstock. These paddocks get a heavy build-up of worm larvae over time. Ideally, lambs should go onto ‘clean’ pasture. Assigning a ‘pasture risk’ to your fields can help with this.

As ever, continue to use Faecal Egg Counts to reduce wormer usage in your flock. With ever-increasing resistance to available worming products and no new products coming to market, we really must ensure these products continue to work long term!

Always remember to follow up every wormer treatment with a Faecal Egg Count Reduction test to see how well your wormer has actually worked!