MOLDY GRAINS, MYCOTOXINS AND FEEDING PROBLEMS 

                                                                                       

Erick DeWolf, Plant Pathologist, Penn State University

Gretchen Kuldau, Plant Pathologist, Penn State University

Patrick Lipps, Plant Pathologist, The Ohio State University

Gary Munkvold, Plant Pathologist, Iowa State University

Paul Vincelli, Plant Pathologist, University of Kentucky

Charles Woloshuk, Plant Pathologist, Purdue University

Dennis Mills, Extension Associate, The Ohio State University

 

Introduction

Aflatoxins

Zearalenone

Trichothecenes (DON, T-2)

Fumonisins

Ochratoxin

Preventative Practices

Detrimental Feed Concentrations

What is ppm & ppb?

Plant Disease Associations

Links

 

Fungi produce an array of chemical products known as secondary metabolites. Penicillin is an example of a secondary metabolite with medicinal applications. Unfortunately, not all secondary metabolites are as useful as penicillin. Mycotoxins are secondary metabolites of fungal origin that are toxic to animals and humans. Disease that results from ingestion of mycotoxin-contaminated feed or food by animals or humans is called mycotoxicosis. Common examples of mycotoxicosis are mushroom poisoning and ergotism.

 

Among the thousands of species of fungi, only about 100 are known to produce mycotoxins. Under favorable environmental conditions, some toxigenic molds can produce mycotoxins on agricultural commodities during plant growth, or after harvest in storage and shipment. Some of the agricultural commodities affected are cereal grains, soybeans, peanuts and forage crops. Mycotoxin-contaminated feeds are of critical importance due to their potential hazard to livestock and poultry. Additionally, contaminated food grains can affect human health.

 

In the Midwest, the most common feed sources with mycotoxin contamination problems are corn, wheat, forage and silage crops.  However, producers should be aware that mycotoxin problems can be associated with grains and grain products purchased off the farm or mixed in feed rations. Mycotoxin problems are often aggravated by poor storage conditions.

 

General symptoms of mycotoxicosis in domestic animals are: loss of appetite, poor weight gain, feed refusal, diarrhea, bleeding and unthriftiness.

 

Mycotoxicosis is generally characterized by the following features:

  • The disease is not contagious

  • Antibiotics and drugs have little effect in controlling the disease

  • Outbreaks are often seasonal

  • The problem is associated with a specific feed

  • Analytic assay of the feed indicates the presence of toxic metabolites.