Facial eczema is a disease which commonly affects cattle, sheep and alpacas. It occurs when animals eat fungal spores found at the base of the pasture. These fungal spores release toxins which can cause liver damage and skin peeling photosensitisation. Once the liver is badly damaged it cannot regenerate and this can lead to death or chronic wasting. The risk season usually runs between January and May, but is dependent on moist warm soil temperature. Some key signs to look for with your animals include shade-seeking or animals separating themselves away from herd mates, loss of condition, head shaking, sitting down and looking sad, jaundice yellowing gums , sunburn and skin peeling.
Facial eczema prevention and diagnosis with Franklin Vets
Facial eczema is a type of sunburn photosensitisation affecting exposed areas of pale skin of sheep and cattle. It is caused by a poisonous substance called "sporidesmin", which is produced on pasture plants by the fungus Pithomyces chartarum. Major outbreaks occurred in sheep in and , and in cattle on irrigated pasture in Sporadic cases, mainly in sheep, have been recorded in other parts of Victoria. The disease in stock may be seen between seven and 20 days of pick-up of the toxic spores from the pasture. The toxin is absorbed from the intestine and reaches the liver, where it causes severe damage, first to the bile ducts and then to the liver cells themselves.
Move early against facial eczema
Sheep are most susceptible followed by dairy cattle, beef cattle, and red deer. Animals get FE after eating large numbers of fungal spores Pithomyces chartarum which contain the toxin sporidesmin. Sporidesmin causes liver damage which can then lead to photosensitisation. Photosensitivity occurs because the FE damaged liver cannot breakdown grass pigments from grass that the animal has eaten. However these classical skin lesions are only the tip of the iceberg but that is what everybody sees on the outside.
This case study outlines a disease investigation that was in response to a farmer contacting the Emergency Disease hotline. The syndrome reported by the farmer could have been consistent with an exotic disease. The case study outlines the approach that the Cumberland LHPA took to reach a diagnosis and exclude important exotic disease.