Facial eczema prevention

Facial eczema is a disease which can affect grazing ruminants and camelids. It occurs in the late summer to autumn (January to April). It causes a skin disease where the whiter, less hair covered, areas of the animal will appear like sunburn.

Facial eczema is caused by fungal spores (Pithomyces chartarum) in the grass and is ingested when stock are grazing particularly getting low grass.

This then causes damage to the liver bile ducts from a toxin in the spores (sporedesmin). This damage leads to accumulation of phytoporphyrin which when exposed to sunlight causes skin damage.

The white hair or hairless areas are more likely show lesions but liver damage can still occur in animals with darker coats but not seen as bad visibly.

Cattle: Any white patches and particularly the udder are common sites for skin lesions in cattle. Sheep: With their woolly coats sheep may be seen with lesions around the eyes, muzzle and ears where wool cover isn’t as thick. They may be seen scratching against posts. Most breeds will be susceptible and zinc treatment is important during the risk period. Sheep graze pasture quite low putting them at risk for picking up the fungal spores contributing to facial eczema.

Goats: Goats are less likely to be affected by facial eczema. Part of this is due to their browsing nature and not grazing down as low on pasture but there is also resilience against the sporodesmin toxin as well.

Alpacas: Alpacas are very susceptible to facial eczema toxicity. Zinc treatment is difficult in alpacas and a focus should be on reducing sporedesmin intake. Fungicide on the pasture or reducing pasture intake during the at risk period are the best ways to manage facial eczema in alpacas.

There is no specific treatment for facial eczema and when lesions appear the liver damage has been done. Treatment consists of supportive therapy.

Reducing problems associated with it include keeping animals under shade, zinc cream, and when toxic supportive therapy.

With facial eczema prevention is the best option, whether by fungicide, zinc or by avoiding grazing during the risk periods.

If your animals do get facial eczema it is important to keep them under shade to reduce exposure to sunlight.

Zinc supplementation options are great for cattle and sheep.

A ruminal bolus — provides a slow release protection for a longer period (4-6 weeks depending on brand) Zinc oxide slurry drenches can be given weekly Zinc sulphate in water — not effective for sheep, can be variable in cattle Zinc oxide on supplementary feed — daily added to any other feed you might be giving.

Zinc toxicity does occur so ensure that you follow one method of zinc supplementation at the correct dose rate.

To enable zinc to build up to a protective level treatment needs to start two weeks before the risk period, so ideally in January.

Contact your vet to discuss the pros and cons of different zinc treatments for your animals.

Keep an eye on spore counts in your area over the risk period and if you suspect facial eczema call your vet for further information and options.