• 86% contained fumonisins
• 45% contained deoxynivalenol (DON)
• 36% contained zearalenone (ZEN)
• 10% contained aflatoxins

Every corn and feed sample contained at least one mycotoxin, highlighting just how common contamination has become across commercial feed ingredients.

Perhaps more importantly, researchers observed that co-contamination was the rule rather than the exception, with many samples containing two or even three toxins simultaneously.

Corn remains the primary source of exposure

Corn continues to represent the largest source of mycotoxin exposure in North American poultry diets. Because corn typically accounts for the majority of dietary energy, contamination can rapidly affect large portions of commercial feed formulations.

Surveys of U.S. corn harvested between 2018 and 2022 found that fumonisins were particularly prevalent, especially in corn co-products where toxin concentrations were often considerably higher than in whole grain.

Researchers also found widespread contamination with Type B trichothecenes, reinforcing the importance of evaluating complete mycotoxin profiles rather than focusing on a single toxin.

Environmental conditions such as rainfall during flowering, delayed harvest, insect damage, and poor storage conditions all contribute to fungal growth and toxin production.

Hidden losses often exceed visible disease

One of the greatest challenges of mycotoxins is that their impact is often subclinical.

While severe contamination can produce obvious clinical signs, lower concentrations frequently result in chronic production losses that are more difficult to detect but equally costly.

Common consequences include:

• Reduced feed intake
• Poor weight gain
• Reduced feed conversion efficiency
• Impaired gut integrity
• Suppressed immune function
• Greater susceptibility to bacterial and viral diseases
• Poor flock uniformity
• Higher condemnation and culling rates

These subtle effects often translate into significant economic losses across an entire production cycle.

Gut health and immunity are particularly vulnerable

Mycotoxins affect much more than growth performance.

Many toxins damage intestinal epithelial cells, alter the gut microbiota, and compromise nutrient absorption. Others interfere directly with immune function, leaving birds less capable of responding to vaccination programs or infectious disease challenges.

Because modern poultry production relies heavily on maintaining gut integrity and minimizing antimicrobial use, controlling mycotoxin exposure has become increasingly important within comprehensive flock health programs.

Testing is becoming standard practice

Given the variability between harvest years, geographic regions, storage conditions, and ingredient suppliers, routine testing has become one of the most effective management tools available.

Feed mills and integrated poultry companies increasingly rely on analytical testing to characterize incoming raw materials and adjust formulation strategies accordingly.

Risk assessment should include:

• Raw ingredient screening
• Finished feed monitoring
• Supplier quality programs
• Harvest-year evaluations
• Regional contamination trends

Mitigation requires a multi-layered strategy

No single intervention completely eliminates mycotoxin risk. Successful control programs typically combine multiple approaches throughout the production chain.

Common mitigation strategies include:

• Routine ingredient testing and surveillance
• Careful supplier selection
• Proper grain drying and storage
• Moisture management
• Use of approved mycotoxin binders or adsorbents when appropriate
• Biotransformation technologies capable of degrading specific toxins
• Nutrition programs that support intestinal integrity and immune function

Increasingly, producers are adopting integrated feed safety programs that combine prevention, monitoring, and mitigation rather than relying on any single solution.

Climate variability may increase future risk

Climate variability is expected to continue influencing fungal growth patterns across North America. Wetter growing seasons, temperature fluctuations, and extreme weather events may alter both the prevalence and distribution of major mycotoxins.

As grain production adapts to changing environmental conditions, poultry producers will likely require more dynamic surveillance systems and increasingly flexible mitigation strategies.

Outlook

The evidence is clear: mycotoxins remain a persistent feed safety challenge for North American poultry production.

Fumonisins, deoxynivalenol, zearalenone, and aflatoxins continue to dominate contamination profiles, while multiple-toxin exposure adds further complexity to risk assessment.

Looking ahead, producers who invest in comprehensive feed safety programs, regular ingredient monitoring, and science-based mitigation strategies will be better positioned to protect bird health, maximize production efficiency, and maintain profitability.