Facial Eczema in Alpacas

By Beryl Thomas, Egmont Alpacas

Leaf litter.

Alpacas are one of the most sensitive animal species to facial eczema. We need to be vigilant and aware of what is happening at the base of our pasture during the facial eczema (FE) season, which can run from January through until May each year, depending on the weather conditions. FE is a concern throughout the North Island, and the top part of the South Island.

The fungus Pithomyces Chartarum produces spores which contain Sporadesmin - the cause of facial eczema. The fungus requires a base grass temperature of >10 deg C, for 2 - 6 days and moisture equivalent to 5mm of rain for it to survive and replicate.

Heavy dews and high relative humidity produce the same effect. The fungus grows on dead leaf litter at the base of the pasture.

Facial eczema effects

Alpacas ingest spores and in the gut the toxin is absorbed into the blood and transported to the liver. The toxin causes inflammation of the bile duct which closes, not allowing bile to be excreted. Bile seeps back into the liver and blood. The damaged liver cannot void the wastes and a chlorophyll derivative accumulates in the tissues. The animal becomes photosensitive, and tends to seek shade. If exposed to sunlight an immediate and severe inflammation of the skin occurs.

From the time the animal ingests the spores to first symptoms is about ten days. Considerable liver damage will have already occurred. Those severely affected may die. Animals which may not show outward signs of FE may die during pregnancy, lactation or other periods of stress. The liver has the ability to regenerate healthy tissue and allowed rest and a nutritious food supply, affected animals may recover.

Facial eczema control

There are several different approaches to facial eczema control.

Clean pasture base.

The standard prevention method for FE in alpacas is to spray the pasture with a fungicide, every month to six weeks, and to feed alpaca zinc nuts at a rate of 200grams per animal per day, during the FE season. It should be noted that administering zinc by way of zinc bullets is not effective for alpacas. For more info visit: www.alpaca.org.nz

Organics prevention creates a healthy soil, for healthy pasture and healthy animals. Lime, and organic fertiliser, plus soil microbes, stimulate earthworm activity. Earthworms draw the dead leaf litter down into the soil, keeping the base of the pasture clean providing a habitat inhospitable to the fungus.

FE Nosode is a homeopathic support treatment. The liquid may be added to water troughs or drenched orally. For more info visit: www.farmsupport.co.nz

Taranaki case study

FE testing kit.

The north Northern Taranaki coast has high spore counts during the FE season. We have a regime in place spraying our pasture for 2 weeks from 15 December, and then we spray monthly to the end of April, this also covers May because the spray lasts for 6 weeks.

Spraying does not kill the spores that have already developed. This is why we start well before the spore counts start to rise. We have our own spore testing kit, and regularly test our pasture.

There is a large variation of spore counts in different paddocks. We would suggest local spore count numbers in your areaare a guide only. A general count for your area may be 2000 spores when the paddock you are grazing has a count of 40,000.

From mid December we start to introduce alpaca nuts which have zinc added. We begin with a teaspoon of zinc nuts mixed with their ordinary nuts and increase the amount of zinc nuts until we feed only zinc nuts from January. FE treatment must be in the animals' system two weeks before FE season strikes.

In alpacas the use of zinc over 90 days can inhibit uptake of copper. We put copper pipe in each water trough, so copper leaches into the water. Copper levels may be checked by a blood test.

We minimise dead leaf litter by topping paddocks with a mower + catcher. All mown grass must be collected.

Fodder plants which have high zinc include chickory, and two poplar tree varieties, Populus Yunnanensis and Populus Androscoggin.

Beryl and Glenn.

Author profile

Beryl Thomas and Glenn Skedgwell own and operate Egmont Alpaca Stud at Onaero in Taranaki. Beryl was a dairy farmer before she started in alpacas in 2002.

Egmont Alpacas have a tourist facility and retail outlet on the premises. They have a selection of animals for sale and provide stud services by top international stud males. For more info visit: www.egmontalpacas.co.nz