There are no clear-cut safe feeding levels. To feed at a level other than 0 ppb is a risk assumed by the person making the decision to do so. Conclusion Aflatoxins are highly toxic to livestock, poultry and people. Even fed at nonfatal levels, aflatoxin can seriously impair animal health and productivity. For lactating dairy cattle, do not exceed 20 ppb aflatoxin in rations to avoid exceeding the food and Drug Administration level of 0.5 ppb in milk.
Aflatoxin is just one of many mycotoxins that can adversely affect animal health and productivity.