A silent thief of milk production and heifer growth, facial eczema (FE) is a damaging yet often overlooked liver disease affecting cattle in New Zealand.
Despite its name, FE is not a skin condition; it’s a liver disease caused by ingesting spores from the fungus Pseudopithomyces toxicarius, which grows in the dead litter of pasture and thrives in warm, humid conditions experienced in late summer and autumn. These spores contain sporedesmin, a toxin that attacks the liver’s bile ducts, resulting in impaired liver function, causing a build-up of toxins and reduced production of fats, proteins and energy essential for growth and production.
What makes FE especially dangerous is its sub-clinical nature. Up to only one in 10 animals with liver damage show the classic sunburn-like symptoms, while hidden internal liver damage often goes unnoticed until production losses become evident.
What are the production impacts of FE on-farm?
The impact on young stock can be particularly severe. Liver damage from FE can significantly knock back growth rates and result in long-term reductions in productivity. Research shows that heifers affected by FE often not only fail to meet growth targets but can also suffer lifetime milk production losses of up to 25%1. This is a huge hidden cost to farms, as fewer heifers reach target weights, they produce less milk and often exit the system before recovering their rearing costs.
Another New Zealand study2 investigated the impact FE has on milk production and found that even cows with very mild liver damage and no clinical signs suffered a drop in milk production of 0.14-0.35kgMS/day. This may sound minimal, however, it represents a significant economic loss. For example, a 600-cow herd with 20% of cows sub-clinically affected could be losing up to $37,800 in lost milk production alone3. To estimate what FE is potentially costing your farm system, DairyNZ offers a “Cost of subclinical FE” calculator online.
How can you prevent FE?
Using spore counting as a tool to identify the risk period (counts consistently at 30,000 or greater), an FE programme can be put in place before there are production losses.
The most effective way to prevent FE is through zinc supplementation, as when given orally, zinc neutralises the sporedesmin toxin. Zinc can be administered via water or feed, but these methods can be inconsistent, particularly in young stock, as they rely on individual animal intakes. To measure the effectiveness of zinc supplementation, zinc can be measured from blood tests or “Zinc Check”, a simple bulk milk test available to Fonterra suppliers.
For reliable protection, Agritrade’s Time Capsule zinc bolus offers a solution developed specifically for New Zealand conditions. Providing a consistent daily zinc dose and reaching protective levels within 48 hours of administration, the Time Capsule is a great proactive and reactive option. It offers four weeks of protection in cattle, with no withholding period, and is available in sizes suitable for all classes of stock. Cattle may also be safely retreated at four weeks if the risk period continues.
Proven under New Zealand conditions, a 2019 trial4 showed that heifer calves treated with the Time Capsule exhibited no indicators of liver damage and gained 15kg more than untreated calves after three months of facial eczema exposure.
Knowing the damage FE can cause, effective proactive prevention is key.
Speak to your local Technical Sales Representative or visit your Farm Source store today about how the Time Capsule can help prevent FE from stealing your herd’s milk production and young stock’s lifetime performance this season.
