In January, Volac hosted a farmer-focused technical event in the Netherlands centred around the principle “Meten is Weten” – Measuring is Knowing.
Held in Tjerkgaast, the evening brought together dairy farmers, nutritionists and feed mill partners to explore how data-driven insights can support better decision-making on farm. With over 120 attendees representing around 200,000 cows, the event created a strong platform for sharing real-world data, discussing challenges and aligning on practical solutions for improving herd performance.
The session combined live farm data, Mycocheck risk assessments and laboratory analysis to provide a clearer understanding of mycotoxin and endotoxin pressure within dairy systems. In total, 186 feed samples were analysed across mixed rations and concentrates, reinforcing a consistent and important message, mycotoxins are not a one-off issue, but a continual background risk that needs to be actively managed.
A hidden but widespread challenge
Mycotoxins are naturally occurring compounds produced by fungi and are present in most feed materials. Because they are invisible, odourless and stable, they often go unnoticed, yet their impact on performance can be significant.
The data presented at the event highlighted just how common this challenge is, with the majority of samples containing multiple mycotoxins at varying levels of risk. This variability makes mycotoxins particularly difficult to manage, as levels can fluctuate depending on climate, crop stress and storage conditions.
Understanding the impact on the cow
One of the key discussion points during the evening was how mycotoxins actually present on farm. Unlike many health challenges, they rarely cause clear or acute symptoms. Instead, they often contribute to subtle performance issues that can be difficult to pinpoint.
Common signs discussed included:
Slight reductions in feed intake
Inconsistent milk yield or components
Increased pressure on hoof and udder health
Because these symptoms are non-specific, mycotoxins are often overlooked. However, they can play a significant role in reducing immunity and increasing the cow’s sensitivity to other stressors.
Higher-risk groups include transition cows, early lactation animals and high-yielding cows, particularly where rumen function is already under pressure.
Multiple mycotoxins, combined impact
A key takeaway from the event was that mycotoxins rarely occur in isolation. Instead, multiple toxins are typically present within a ration, often at low levels but capable of interacting and compounding their effects.
The most common groups highlighted were:
Fusarium toxins (field origin): DON, ZEA and fumonisins
Storage fungi toxins: aflatoxins and ochratoxins
Around 85% of contamination originates in the field, with the remainder developing during storage. This reinforces the need for a broad and balanced approach to risk management, rather than focusing on a single toxin.
From reactive to proactive management
A central theme of the event was the shift from reacting to problems, to proactively managing risk through measurement and monitoring.
By using tools such as Mycocheck, farmers and nutritionists can begin to:
Identify risk patterns over time
Understand seasonal variation
Make more informed feeding decisions
Alongside monitoring, the importance of good forage and clamp management was strongly emphasised. Preventing heating, minimising oxygen exposure and maintaining silage quality all play a critical role in reducing mycotoxin development.
Supporting performance through nutrition
While strong management is essential, nutritional strategies also have a role to play in mitigating risk. The event highlighted the value of solutions that both bind a broad spectrum of mycotoxins and support rumen function.
This is particularly important given the increasing recognition of endotoxins as an additional challenge, especially in situations involving rumen stress, acidosis or feed instability.
Strong engagement and clear next steps
The event generated excellent engagement from both farmers and feed mill partners, with strong interest in moving towards more structured monitoring and proactive risk management.
Early outcomes include:
Increased discussion around seasonal contamination trends
Strong interest in implementing Mycocheck programmes
Growing awareness of endotoxins as an under-recognised risk
Several follow-up conversations and on-farm projects are already underway, with continued engagement planned across the Dutch market.
Protecting performance through better insight
The key message from the evening was clear: mycotoxins are an ever-present challenge, but with the right tools, data and management strategies, their impact can be reduced.
By combining measurement, good on-farm practices and targeted nutritional support, dairy producers can take a more proactive approach - protecting cow health, maintaining performance and unlocking greater consistency from their herds.