PIERRE, S.D. (AP) - South Dakota agriculture officials are advising farmers and ranchers to test for aflatoxin levels in their corn, distiller's grains and silage piles due to this year's drought.

SDSU Extension educators say feed refusal, reduced growth rate and decreased feed efficiency are the predominant signs of chronic aflatoxin poisoning in livestock. High levels of aflatoxin fed to dairy cows can lead to contamination of the milk that is produced.

The National Corn Growers Association says aflatoxin is most prevalent in corn, cotton, peanuts and tree nuts. Aflatoxin is most commonly related to drought-stressed corn, followed by periods of high humidity.

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