Facial eczema has been a heavily discussed topic over recent months, with spore counts remaining elevated much longer than usual. This has meant cumulative spore ingestion by stock has been greater this season, and more cases of clinical facial eczema have been identified in the last few weeks.  

In New Zealand, facial eczema is caused by ingestion of spores from the fungus Pithomyces chartarum, which grows on dead pasture litter during warm, humid conditions, particularly in late summer and autumn. Even animals that do not show clinical signs may suffer significant subclinical liver damage, which can impact production, fertility, and overall resilience long term.  

With or without severe sunburn, clinical facial eczema can present in several ways:  

• Sudden drop in production  

• Sudden ill-thrift  

• Blood in urine  

• Yellowing of gums and vulval membranes (jaundice)  

• Hunching and posturing to relieve pressure on the upper abdomen. 

These presentations are all consequences of progressive and severe liver damage. This damage is also present in subclinical facial eczema; however, the difference is that the total amount of spores ingested over time is greater in clinical cases.  

Several factors contribute to the progression from subclinical to clinical facial eczema, including:  

• Discontinuing zinc supplementation too early  

• Grazing below 1500kgDM/ha  

• Previous liver damage  

• Moving stock onto highly contaminated pasture. 

Before heading into next summer, it is important to plan ahead and begin zinc supplementation early, using a method that ensures every animal receives an effective dose. Prevention is key when dealing with facial eczema.  

To discuss this topic further, or if you would like assistance developing a zinc plan for next season, we’re always happy to help.