Mycotoxins in pig feed

Mycotoxins are poisonous chemicals which can affect the health of your pigs. Learn more about the symptoms of exposure and how you can minimise the risk.

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What are mycotoxins? 

These poisonous chemicals are produced by moulds and fungi, which can be present on various crops. Under favourable environmental conditions - which differ depending on the fungus - moulds can multiply and may produce mycotoxins. Most need a moist, warm environment, with a ready supply of oxygen and carbohydrates to grow. The presence of mould or fungi does not necessarily mean that mycotoxins are present and neither does the absence of visible mould.


According to the Food and Agriculture Organization (FAO), 25% of the crops harvested around the world are contaminated with mycotoxins. Mycotoxins are considered to be a major issue because of their harmful effects on animals and humans. Over 400 mycotoxins have been identified; however, only a few have a toxic effect on pigs or humans and are therefore of concern. Acute, highly visible effects are seen at high levels, but relatively little is known about chronic, less visible and slower-to-present effects at low levels, or about their synergistic effects (how they interact with other toxins).

Symptoms of mycotoxin ingestion

The main fungal species that produce mycotoxins of concern for pigs are Fusarium spp., Aspergillus spp. and Penicillium spp. The pig’s response to mycotoxin ingestion depends upon the level ingested; the type of mycotoxin; the age, weight and health status of the pig; the length of exposure; and the dose. However, possible symptoms include:

  • Reduced growth rate
  • Increased food conversion ratio
  • Feed refusal
  • Immunosuppression
  • Vomiting
  • Infertility; for example, abortion, stillbirths, low viability piglets
  • Liver damage
  • Kidney damage

Reducing mycotoxin exposure

To minimise pigs’ risk of exposure to mycotoxins, cereals and feedstuffs must be correctly stored on farm and special attention paid to cleaning equipment.

Mouldy grain or feed should never be fed to pigs and similarly mouldy straw should not be used as bedding. Pigs of all ages are susceptible to mycotoxins but as some mycotoxins are oestrogenic, sow performance is particularly affected.

The following procedures should be followed to minimise the risk of mycotoxin production and contamination during storage of cereals and feedstuffs:

  • Regular bin cleaning
  • Regular cleaning of feeder lines
  • Storage condition of grains – avoid warm or damp grains
  • Storage condition of feed
  • Maintain storage facilities to avoid leaks

Mycotoxin binders are most often used to protect animals against mycotoxins. Mycotoxin binders are binding agents that can selectively bind and immobilise mycotoxins in the gastrointestinal tract of the animal, thereby preventing absorption in the gut and allowing the mycotoxin to pass harmlessly through the pig.

While mycotoxin binders are available to reduce the effects of mycotoxins in feed, they should not be relied upon for complete protection as they are not 100% effective. It is also unclear whether mycotoxin binders are effective if the mycotoxin is coming from straw, so it is important to minimise pigs’ risk of exposure to mycotoxins, rather than solely relying on a mycotoxin binder.

This was written in conjunction with ABN, Primary Diets and Premier Nutrition.