ZincCheck can save facial eczema pain and production losses

Restless cows who have lost their appetite may be suffering from facial eczema.

Hot temperatures and humid, wet weather can provide the ideal environment toxic fungal spores to grow in pasture, which can lead to facial eczema in cows once ingested.

The spores of the fungus Pithomyces chartarum grow on dead matter at the base of the pasture sward and can cause a range of serious health issues for cows including liver damage, photosensitivity and issues with reproduction.

For every clinical case in a herd, it’s estimated there are up to 23 sub-clinical (invisible) cases¹.

Telltale signs of sub-clinical facial eczema include restlessness, shade seeking, loss of appetite, drop in milk production and diarrhoea. In the worst cases, facial eczema can be fatal. 

Fonterra Veterinary Programme Manager Mike Shallcrass says subclinical facial eczema can cost 1kg of milk solids (kgMS) per cow per week, while severe facial eczema can more than double that.

Facial eczema is prevalent between January to May due to environmental conditions, however cows may be affected any time, particularly when they are under stress such as calving.  

While there is no cure for facial eczema, being proactive with preventative measures can help to protect your herd, with zinc recognised as the strongest protection currently available.

"Most New Zealand cows are not getting enough zinc to maximise their defence against the disease because there is a threshold zinc levels need to reach in the blood to achieve protection," Mike says.

“We’ve tested the blood of cows around the country and found that many cows haven’t been getting the right dose we would consider to be protective. Even though the zinc dose ramps up, there’s a threshold. At some point, it crosses over and is protective but until then it’s sub-therapeutic.”

Mike recalls instances where farmers were caught out because they’d only ever had a couple of clinical cases, so assumed their zinc dosing was right. However, he warns that facial eczema is a “tip of the iceberg” disease, and that even if a farm only has a small number of animals with skin disease, there are likely to be many more sub-clinical cases, which is where the majority of production loss comes from.

On Farm Excellence Milk Project Manager Paul Jamieson says Farm Source’s ZincCheck can help farmers assess their zinc dosing.

"ZincCheck takes a herd-level approach, with a bulk milk test to determine if at least 70% of the herd have enough zinc in the blood to pass across into the milk," Paul says.

“We use 70% because the natural variation we see in the herd means some animals won’t be getting that high and some will be higher, but by testing the sample we can determine the level of zinc and then take that back to the research done and it will indicate whether you've got insufficient zinc, sufficient zinc, or if your herd is potentially moving into the toxic levels of zinc.”

Co-op farmers can access their first ZincCheck for free (thereafter it’s $99 per test). It’s easy to book online and saves the worry of cows suffering subclinical impacts without knowing.