Eczema in dairy heifers, often referred to as Facial Eczema (FE), isn’t just a skin issue—it’s primarily a serious liver disease that can significantly impact your young stock’s growth, future production, and overall health. As a critical part of your future herd, protecting your heifers from FE is paramount.

Here is a simple guide to understanding the cause and implementing effective management strategies.

What Exactly is Facial Eczema?

Despite its name, Facial Eczema is caused by a toxin that attacks the liver.

• The Culprit: The disease is caused by a toxin called sporidesmin, which is produced by a fungus (Pseudopithomyces toxicarius, formerly Pithomyces chartarum).
• Where it Grows: This fungus thrives in the dead litter at the base of pasture, especially during warm, humid conditions. This is often a risk period from late summer into autumn.
• The Damage: When a heifer ingests the spores, the sporidesmin toxin damages the liver and bile ducts. A damaged liver cannot properly remove a chlorophyll breakdown product (phylloerythrin), which then builds up in the bloodstream.
• The “Eczema”: This build-up causes photosensitization, meaning the unpigmented or exposed skin (like the face, ears, and udder) becomes extremely sensitive to sunlight, leading to the painful, reddened, swollen, and peeling skin lesions characteristic of “eczema.”

Crucial Note: For every heifer that shows the visible skin signs (clinical FE), there are many more with unseen subclinical liver damage, which can still severely affect growth rates and future productivity.

 Management and Prevention for Heifers

Since there is no cure for existing liver damage, prevention is the only effective strategy. Your focus should be on reducing the ingestion of toxic spores during the danger period.

1.

• Spore Counting: This is your most valuable tool. Regularly monitor your regional spore counts as a warning sign. More importantly, have your own farm’s pasture spore counts tested weekly during the risk period (late summer/early autumn) to pinpoint when your specific paddocks become dangerous. 
• Here at NZ Grazing, we supply our grower farmers free, the ability to utilise the Techion Faecal Spore Count (FSC) testing system. Faecal spore counting is not as accurate as pasture spore counting due to the variability of the water content in faeces, but it does provide a useful guide.

• Weather Watch: Be ready to implement control measures as soon as the weather turns warm and humid, especially after rain, as this triggers rapid fungal growth.

2. Zinc Supplementation

Zinc is the most common and effective preventative measure as it binds to and inactivates the sporidesmin toxin.

• Accurate Dosing: Heifers, like all cattle, must receive an accurate, full protective dose based on their individual weight. This is essential to ensure a protective level of zinc in their blood.
• Delivery Methods for Young Stock:
• Zinc Boluses (Capsules): These are often the most reliable method for dry stock like heifers, as they provide a consistent, slow-release dose for several weeks.
• Drenching: Drenching with a zinc oxide slurry is another option, although it is more labour-intensive and may need to be done weekly for heifers.
• Trough Dosing. This can be very hit and miss due to the change in the taste of water and how much the heifers drink.

3. Pasture and Grazing Management

Reduce the chance of heifers eating the spore-laden dead litter at the base of the pasture.

• Avoid Hard Grazing: Do not graze paddocks down to a very low residual. Leaving longer residuals means the heifers consume less of the base litter where the spores concentrate.
• Alternative Feed: During high-risk periods, supplement the heifers’ diet with silage or non-grass feeds (like chicory or plantain) to reduce their overall intake of potentially toxic pasture.
• Graze “Safe” Paddocks: Use paddocks known to be low-risk (e.g., those sprayed with fungicide, or those with different pasture species) for your heifers during danger periods.

4. Treatment for Affected Heifers

If you see signs of FE in your heifers (restlessness, shade-seeking, red/peeling skin), take immediate action to provide supportive care: seek medical advice from your veterinarian immediately.

Protecting your dairy heifers from Facial Eczema is an investment in your farm’s future. By monitoring spore counts and implementing a consistent zinc supplementation program, you can significantly reduce the risk and ensure your young stock grow into healthy, high-producing cows. And a win-win for both the Owner and the grower. 

Words by Ruth Kitchen, Northland Service Manager.