Facial eczema affects all types of livestock in New Zealand - sheep, dairy cows, beef cattle, and deer.
Facial eczema affects all types of livestock in New Zealand - sheep, dairy cows, beef cattle, and deer.
Content brought to you by PGG Wrightson
Heading into the busy summer months on farm, The Country has partnered with PGG Wrightson’s animal production technical team for a three-part series of practical advice for dairy, sheep, and beef farmers across New Zealand.
Hosted by Rowena Duncum, the third and final episode looks at the issue of facial eczema – from the first signs through to treatment options and preventative programmes.
In it, Duncum is joined by Jo Harris, a technical expert in PGG Wrightson’s Animal Production Team.
Harris grew up in the North Island and completed an Animal Science degree at Massey University, before undertaking postgraduate work focused on dairy nutrition - specifically exploring hormones that control lactation and also different feed scenarios.
She highlighted the broader implications for reduced milk and meat production, fertility, and overall animal welfare.
Risk factors and climate change
While the fungus responsible for facial eczema exists year-round, the spores that contain the toxin sporidesmin, only thrives in warm or humid conditions, or where there is a lot of dead leaf matter —typically from midsummer through autumn.
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Climate change has potentially exacerbated the issue, expanding the risk to regions previously unaffected, including parts of the South Island.
“It’s no longer a question of if areas like Central Otago will see facial eczema, but when,” warned Harris.
Prevention strategies
Facial eczema is caused by a fungus that produces a toxin, sporidesmin, which damages the liver of grazing animals.
Harris outlined practical steps for farmers to develop an effective prevention plan:
- Know Your Risk Areas
Identify paddocks prone to high fungal growth, such as warmer, wetter north-facing areas, with dead plant matter.
Consider using fungicides on high-risk paddocks before spore levels rise.
- Administer Zinc Early
Zinc, particularly in slow-release bolus form, is the gold standard for prevention.
Alternate delivery methods include zinc in feed or water, although these can be less reliable.
- Manage Supplements and Systems
Avoid or reduce copper-rich feeds like palm kernel, which can interfere with zinc uptake.
Ensure proper mixing of zinc into feed to guarantee adequate consumption.
- Test and Monitor
Between 3-6 weeks after starting zinc treatment, test animals for liver enzyme levels (GGT) and zinc to confirm the program’s effectiveness.
Dairy farmers can also use bulk milk testing as a screening tool.
What farmers can do to be prepared
Jo Harris works with PGG Wrightson Field Reps to support farmers across the lower North Island.
As supply chain issues and New Zealand’s proximity to other countries can occasionally cause zinc shortages, Harris advised farmers to plan ahead.
“Don’t rely on ‘just-in-time’ ordering—get your supplies early,” she stressed, recalling past seasons when farmers scrambled to secure treatment options.
Breeding livestock for facial eczema tolerance is showing promise, particularly in sheep.
However, Harris cautioned against relying solely on genetics.
“Genetic advances are helpful, but must be part of a comprehensive prevention strategy,” she said.
Harris encouraged farmers to aim for zero cases of facial eczema.
“It’s not normal to have facial eczema,” she said.
“A well-thought-out prevention plan, implemented early, can make a significant difference.”
For more insights and advice, revisit the Keeping Your Stock Thriving podcast series or talk to your local PGG Wrightson Field Rep.
