Overview

Mycotoxins are toxic compounds produced by fungi in corn and other grains.

Corn grown in Ontario often contains:

  • deoxynivalenol (DON) — also called vomitoxin
  • zearalenone (ZEN)

These mycotoxins develop in warm, wet weather during the corn's flowering stage. This creates ideal conditions for fungal growth.

In hot, dry years when insect damage is present, other mycotoxins like fumonisins can also appear. Rainfall, temperature and timing influence the amount and types of mycotoxins present in corn.

Risks and symptoms

When mycotoxin concentrations are high, poultry producers should be cautious when purchasing and feeding corn and corn by-products. These compounds remain stable during feed processing and can cause:

  • mouth lesions
  • gastrointestinal issues
  • poor nutrient digestion
  • weakened immune systems
  • reduced flock performance

Generally accepted DON levels for poultry is 5 ppm.

How to manage mycotoxins in poultry feed

If you buy complete feed

Contact your feed company if you have concerns about mycotoxins.

If you make your own feed

Test ingredients for mycotoxin levels before use. This is especially important for corn by-products like corn distillers dried grains with solubles, which contain about 3 times more toxins than whole corn.

Use these resources to help you test feed ingredients for mycotoxins:

Dilute contaminated corn

Mix contaminated corn with clean ingredients to reduce toxin levels. You can use:

  • clean corn
  • barley
  • oats
  • wheat
  • alternative feed ingredients like bakery waste or wheat shorts

Avoid corn by-products because they have higher toxin concentrations.

Consider feed additives

Talk with your feed company or nutritionist about feed additives.

While no product removes mycotoxins, some additives can help bind certain toxins and reduce their impact.

Increase nutrient density

Fortify rations with more protein, energy and minerals to help offset performance loss.

Clean feed and protect workers

Screen out fines before storage and feeding.

Workers should take precautions to avoid skin contact or inhaling dust that may contain mould and mycotoxins.