Dwarf Bunt Infected Wheat for Pigs

An unpleasant fishy odour is often the first sign for producers that they have Dwarf Bunt. Dwarf Bunt, and its close cousin Common Bunt, are diseases caused by a fungus that infects the heads of wheat, replacing the kernels with small, black soot balls. These bunt balls are easily broken on handling, releasing black fungus spores that have a strong fish odour.

Dwarf Bunt does not pose any animal or human health risk and, to date, there is no evidence that the feeding value of wheat infested with Dwarf Bunt is significantly different from that of regular wheat. However, high levels of bunt balls and spore dust may reduce feed intake because of the unpleasant odour and taste.

Once the wheat is harvested, it is important to prevent cross-contamination with clean wheat. If bunted wheat is destined to be used in swine rations, the first priority should be to clean out as many of the bunt balls as possible. The fewer bunt balls remaining in the wheat the better. This decreases the chance that broken bunt balls will re-infect the wheat with the fishy-smelling spores when it is handled later. Secondly, aerate the wheat for an extended period of time, for two months or more, to allow the odour to dissipate.

In general, diets containing wheat should be balanced on a lysine basis. Good performance usually results when wheat replaces 50% of the corn in the diet. However, it is possible to feed wheat up to 100% of the grain portion in the diet and get good performance. It is very important when using wheat in the ration to pay close attention to processing. Grind wheat-based diets coarsely (i.e. through a 4.5 to 6.4 mm screen) to avoid dustiness and increase palatability.

For more information:
Toll Free: 1-877-424-1300
E-mail: ag.info.omafra@ontario.ca
Author: Greg Simpson - Swine Nutritionist/OMAFRA
Creation Date: 28 July 1999
Last Reviewed: 29 Febuary 2012