Promising early results for facial eczema lab test

Photo / File

A pilot study investigating the potential for a laboratory test to determine facial eczema tolerance has had positive initial results, paving the way for more detailed investigation.

The study is funded by Beef + Lamb New Zealand and conducted by AgResearch.

The ultimate aim of the study was to produce a fully validated high through-put commercial test, which was readily available for breeders and commercial farmers, Dan Brier, Beef +Lamb New Zealand's General Manager Farming Excellence said.

"Initial results look promising with the establishment of a cell culture method, using sheep and cattle blood, to demonstrate sporidesmin (the toxin that causes facial eczema toxicity," Brier said.

"This indicates that animals could be tested for tolerance without needing to be exposed to the toxin."

Saliva tests also showed some promise and could be explored further to form the basis of a diagnostic test, Brier said.

"Put simply, the overall results of this pilot study were positive and build a strong case for progressing to the next phase in the development of a commercially available test for farmers."

A simple laboratory test would revolutionise facial eczema testing in this country, Brier said.

Currently, the only method of testing for facial eczema tolerance involved exposing a ram to the toxin and observing the toxic effects.

The challenges of using this test led to low numbers of rams being assessed every year.

"Facial eczema is estimated to cost the New Zealand livestock industries up to $200 million per year and a simple lab test would give both breeders and commercial farmers the ability to select animals that are genetically more tolerant to the toxin and therefore carry on producing in the face of a seasonal challenge."

It caused damage to an animal's liver and the secondary effect of the liver damage was photosensitisation leading to skin lesions.

The effects of facial eczema can include poor lifetime performance, reduced fertility and fecundity and increased culling.