Mycotoxins are toxic compounds produced by certain moulds and fungi, most commonly during silage spoilage. The primary culprits in silage are:
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Aspergillus (produces aflatoxins)
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Fusarium (produces DON, Zearalenone, T-2 toxin)
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Penicillium (produces ochratoxin and roquefortine)
Risks to Livestock
The presence of mycotoxins in silage can have serious consequences for animal health and performance:
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Reduced Feed Intake
Animals often reject silage contaminated with mycotoxins due to off-putting odours or tastes. -
Immune Suppression
Mycotoxins weaken the immune system, increasing the risk of disease and infection. -
Poor Performance
Contamination may lead to reduced weight gain, lower milk yields, fertility issues, and even abortions. -
Organ Damage
Prolonged exposure can cause long-term damage to the liver, kidneys, and rumen function. -
Increased Veterinary Costs and Lost Productivity
Even low levels of contamination can result in subclinical symptoms that go unnoticed but ultimately affect performance and profitability.
How to Minimise the Risk of Mycotoxins in Silage
While it's not possible to eliminate mould spores entirely from the environment, it's crucial to prevent the conditions that allow them to thrive. Key recommendations include:
1. Harvest at the Correct Dry Matter
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Target 30–35% dry matter.
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Silage that is too wet or too dry is more prone to spoilage and fungal growth.
2. Wilt Quickly and Cleanly
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Wilt within 24 hours to reduce effluent and inhibit spoilage organisms.
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Avoid contamination with soil, which is a major source of mould spores.
3. Compact and Seal Effectively
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Remove oxygen swiftly using tight compaction and 15–20 cm layers.
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Seal immediately with a high-quality oxygen barrier film such as Silostop.
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Use side sheets and ensure even weighting to prevent air ingress.
4. Use a Silage Inoculant (If Required)
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Select an inoculant that encourages rapid fermentation and pH reduction.
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Some inoculants include antifungal properties to help suppress mould development.
5. Manage Feedout Carefully
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Maintain a clean, tight silage face.
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Remove at least 15–30 cm per day to prevent aerobic spoilage.
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Avoid prolonged exposure of silage to air.
Bonus Tip: Test for Mycotoxins
If you notice issues such as poor performance, digestive upsets, or feed refusals, consider testing your silage for mycotoxins to identify potential hidden problems.
Conclusion
Preventing mycotoxins begins with sound silage-making practices, proper sealing, and vigilant feedout management. Taking these steps not only safeguards animal health but also protects farm profitability.
