Effects of Mold Contamination on Nutritive Value of Feeds

Moldy grain may adversely affect cattle production due to nutrition effects, mycoses or mycotoxicoses. Mycosis is a disease state caused by the fungi themselves, and mycotoxicosis is a disease state caused by secondary metabolites of the fungi. Thus, the mold itself may cause production losses separate and apart from any toxin effects. In fact, various molds have been associated with adverse health effects in plants, animals or humans. In many clinical cases reported it is difficult to separate effects of mycoses from those of mycotoxicoses. Producers generally suspect that mycotoxins are the main culprits for reduced feed intake, diarrhea, abortions, reduced gain or death of their livestock. The objective of this update is to review the current state of knowledge about effects of molds on nutrient content of feeds and mycotoxins (vomitoxin and zearalenone) on ruminant animal performance and health. Additionally, a section to devise recommendations on handling and feeding mold-contaminated grain is provided.