The hidden threat inside the feed bin

For pig producers, every tonne of raw material represents an investment in performance, pig health and, ultimately, profitability. Yet within the feed bin lies an often-overlooked risk that can quietly undermine these goals: mycotoxins. Invisible and odourless, these toxic compounds can infiltrate even the highest-quality raw materials, compromising pig performance and eroding margins long before any outward signs of trouble appear. As pressure mounts on producers to balance cost control with higher productivity and better health, managing this hidden threat has never been more important.

What are mycotoxins?

Mycotoxins are naturally occurring chemical compounds produced by certain moulds and fungi that grow on crops in the field or subsequently during storage. Cereals, forages and feed by-products can all be vulnerable. Ireland’s temperate climate, often marked by wet summers followed by mild autumns, provides the perfect conditions for these moulds to thrive. Even small fluctuations in humidity or temperature during storage can accelerate their growth.

While contamination may begin in the field, improper handling or storage of harvested grains can exacerbate the problem inside the feed bin. That is what makes mycotoxins such a persistent challenge: they are invisible, widespread and easily overlooked until pig performance is noticeably affected. With changing weather patterns and increasingly volatile harvests across many regions in Europe, the risk from mycotoxins continues to require close attention.

Why are pigs particularly at risk?

Pigs are among the most sensitive livestock species to mycotoxins. Their digestive tract, and particularly the intestinal barrier, is highly responsive to these toxins, even when they are present at low levels. This means that pigs can experience health and performance setbacks long before clinical signs become obvious. Low-level, chronic exposure is the most common and the most deceptive form of contamination. It can show up in many ways, such as:

Reduced feed intake and growth rates;

Impaired immune response, leaving pigs more vulnerable to secondary infections;

Reproductive challenges in breeding sows and gilts; and

Subtle digestive disturbances that increase nutrient losses.

Because these effects are often subclinical, they can slowly eat away at farm efficiency without being easily traced back to a single cause. The result is a gradual decline in productivity and profitability across the herd.

The evolving mycotoxin landscape

Alltech 37+ analysis of Irish and European raw materials over successive harvests shows a complex and evolving picture. While deoxynivalenol (DON; see Figure 1) and zearalenone (ZEA) remain the most frequently detected mycotoxins in small grains, other mycotoxins such as fumonisins and ochratoxin A are also increasingly found in feed materials, often in combination.

This mycotoxin cocktail effect is an even greater concern. Multiple mycotoxins acting together can have a cumulative or even synergistic impact, amplifying their negative effects on the gut health, organ function, and immune performance of pigs. In practical terms, this means that even when individual toxin levels are within acceptable limits, the combined challenge can still cause losses for both the pig and the producer.

The Alltech 2026 European Harvest Analysis, which assesses this year’s new-crop grains and forages, will be released in January 2027. Keep an eye on Alltech’s social media channels to sign up and read the full 2026 report as soon as it is released.

Evidence from the field

A published meta-analysis by Weaver et al. (2024) reviewed multiple studies to examine the effects of mycotoxin challenges on growing pigs. The results clearly demonstrated that pig performance is impaired even when mycotoxin contamination levels are below EU and US regulatory thresholds. For instance, pigs exposed to mycotoxins showed a reduction in average daily gain of nearly 80g. Feed intake also declined, compounding the problem.

Importantly, pigs that received Mycosorb, Alltech’s mycotoxin management solution during mycotoxin exposure, maintained significantly better growth rates under both moderate and high challenge conditions. While no single technology can eliminate the risk entirely, these findings highlight how a proactive, data-driven approach to mycotoxin control can protect herd performance and efficiency.

Optimal mycotoxin management

For Irish pig producers, managing mycotoxins effectively starts with recognising that prevention is always more cost-effective than cure. A structured mycotoxin control programme can be built around three simple steps: identify the risk; quantify the risk; and mitigate the risk.

Risk identification: Testing raw materials for mycotoxin contamination is the cornerstone of effective mycotoxin control. Because mycotoxins are invisible, visual inspection alone is unreliable. The Alltech 37+ laboratory analysis, based in Dunboyne, Co. Meath, is one such testing service. It screens feed ingredients for more than 50 mycotoxins across seven groups, giving producers, vets and nutritionists a clear picture of their current contamination status.

Risk quantification: Knowing which mycotoxins are present in a sample is only part of the story; it is important to understand what the test results actually mean for pig health and performance. Alltech’s unique Risk Equivalent Quantity (REQ) metric uses data from the Alltech 37+ analysis to assess the potential impacts on pigs across different life stages, from breeding gilts and sows to weaners and finishers. This detailed quantification allows producers to make informed choices about diet formulation, raw material sourcing and whether further action is needed.

Risk mitigation: Once the risk has been identified and quantified, the next step is mitigation. Alongside good feed storage practices, such as maintaining dry, well-ventilated bins and regular cleaning and maintenance schedules, the inclusion of mycotoxin binders such as Alltech’s Mycosorb® technologies can help to significantly reduce their harmful effects within the pig. Mycosorb® and the EVO solutions, Mycosorb A+ EVO and Mycosorb EVO, are designed to bind a wide range of mycotoxins within the gastrointestinal tract, reducing their absorption and helping to maintain pig health and performance. Backed by nearly 30 years of research, Mycosorb’s safety and efficacy have made it a globally trusted component of integrated mycotoxin management programmes.

Ultimately, controlling mycotoxins is about more than safeguarding feed; it is about protecting pig health, productivity and profitability. When pigs can use feed efficiently and maintain a strong immune system, the benefits are evident at every level: improved growth rates, optimal reproductive performance and a greater ability to cope with disease challenges.

The threat from mycotoxins may be hidden, but its effects are anything but. As Irish pig producers continue to navigate volatile markets, shifting weather patterns and evolving feed supply chains, a proactive approach to mycotoxin management is an investment that delivers measurable returns. For more information on mycotoxin testing, risk assessment tools, and proven mitigation strategies, visit www.knowmycotoxins.com