North Island farmers are being advised to taken precautions to protect their stock from facial eczema, as weather and growing conditions raise the risk levels.
The fungal disease becomes an issue, mainly for North Island farmers, in the late summer and autumn as the spores that spread it to grazing livestock multiply in the base of dried out pasture.
Infected animals suffer liver and skin damage which in severe cases can kill them.
Wayne Baxter of AsureQuality, which monitors the facial eczema risk, says spore counts have risen across most of the North Island.
The facial eczema danger in most of drought-afflicted Northland is relatively low, because there's been little rainfall to get the spores going.
But Wayne Baxter says farmers in areas prone to facial eczema where spore counts are climbing should be taking precautions now, by spraying pasture with fungicide, and treating stock with zinc-based preparations in the form of boluses or adding them to stock drinking water.
However, he says in some herds, treatment in water supplies has not been effective, mainly because the farmers have been setting the treatment rates too low.
Mr Baxter says farmers can find details of this on the AsureQuality website, where they can also check the facial ezcema risk in their area. The RD1 and Meat and Wool New Zealand websites also carry regional spore count updates.
Farmers urged to breed disease resistant sheep
A Northland farm consultant wants farmers there to focus more attention on the facial eczema threat, by breeding sheep that are more tolerant of the disease.
Despite the lower risk in Northland this year, Bob Thomson of Ag First says facial eczema is still one of the main animal health challenges for farmers there.
For the past seven years the region has been "let off the hook", he says, but weather patterns are likely to change and the threat will recur.