The large expansion of the ethanol industry that occurred since 2005 has expanded the supply of co-products for animal feed. Distillers dried grains with solubles (DDGS) is a major co-product of the fuel-ethanol industry and a frequent ingredient of dairy cattle rations. One potential health risk of ethanol production from corn concerns mycotoxins. Several mycotoxins can be found in corn and corn co-products, including aflatoxins, deoxinivalenol, fumonisins, T-2 toxins, and zearalenone.
In a survey of local dairy producers conducted by the dairy science department at South Dakota State University in 2011, farmers ranked the degree of importance of several distillers grains issues (1 = none, 2 = low, 3 = average, and 4 = high). “Mycotoxin content” was rated with a degree of importance of 3.8.
Several experiments have evaluated the mycotoxin concentration of DDGS from the ethanol fermentation process when mold-contaminated grain is used as a substrate. Findings common to all these experiments were:
- An absence of mycotoxins were found in ethanol.
- Minimum degradation of mycotoxins occurred during the fermentation process.
- Mycotoxin concentration was higher in the co-products than the grain of origin.
The heightened level of a given mycotoxin in DDGS was reported to be approximately three times as high as the level in the grain. Moreover, molds can grow, and mycotoxins can be produced in DDGS during transport, storage, and feeding at the farm. Distillers grains are more susceptible to mold colonization than unprocessed kernels because the pericarp that protects the grain has been completely disrupted, which allows for an easier colonization of the remaining nutrients by mold spores.
Continue reading this article published in Hoard Dairyman.
