Alvaro Garcia, SDSU extension dairy specialist, is warning milk producers that there have been reports of aflatoxins showing up in corn in southeastern South Dakota this year and that contaminated feed may poses a threat to dairy cows.
Aspergillus, which produces aflatoxins, is among the most common corn mold fungi. Consumption of low concentrations by animals sensitive to aflatoxins can lead to death in 72 hours. Health and productivity of animals that eat corn contaminated with non-fatal levels of aflatoxins is seriously impaired, Garcia says.
"Research performed at the Virginia Polytechnic Institute suggests that mechanical screening of corn can reduce aflatoxin concentration in contaminated corn," Garcia says. "Samples from a bin were collected with a probe at a depth of 3, 9, and 15 feet. The samples were mechanically shaken to separate fines from intact kernels. The aflatoxin concentration in the whole kernel fractions was 86 to 89 percent lower than that in the fines."
Garcia says that total aflatoxin concentration and concentration in the fines was higher in samples collected at 3 feet than that at the other two depths. These findings show the difference in aflatoxin concentration at different locations within a bin, which underscores the importance of getting a representative sample when assessing aflatoxin concentration. Screening to remove fines can be an effective and practical way to reduce aflatoxin concentration to levels that pose less of a risk when the corn is fed to cattle.
For more information, see agbiopubs.sdstate.edu/articles/FS907.pdf or contact your local county extension office or the SDSU Dairy Science Department at (605) 688-5488.
Source: SDSU AgBio Communications