Fumonisins were discovered in 1988, and fumonisin B1 is the most prevalent form in nature. Fumonisin B1 has no known metabolites, and transfer into the milk appears to be negligible. Fumonisin B1 is carcinogenic in some species, and while less toxic in ruminants, it can result in toxicosis in dairy cattle.
Species Producing Fumonisin
Fumonisins are produced by Fusarium verticillioides (previously F. moniliforme) and F. proliferatum.
Occurrence of Fumonisin
Fumonisin contamination occurs worldwide and has been found in numerous foods and feeds. In dairy rations, corn is the common source of fumonisin contamination. Corn screenings (remnants from processing) are also a source of fumonisin. Transfer of fumonisin to milk is not a concern.
Regulation of Fumonisin
In dairy rations, corn should not contain more than 30 parts per million (ppm) of total fumonisin and should be limited to 50% of the diet. These are not enforceable “action levels,” however, the U.S. Food and Drug Administration considers them an industry guidance.
U.S. Food and Drug Administration Guidance for Levels of Fumonisin in Animal Feed
|Grain or Grain Byproducts||Class of Animal||
Total Fumonisin in Grain or Grain Byproducts and Complete Diet (ppm)
|Corn and corn byproducts not to exceed 20% of the diet**||Equids and rabbits||
|Corn and corn byproducts not to exceed 50% of the diet**||Swine and catfish||
|Breeding ruminants, breeding poultry, and breeding mink*||
|Ruminants ≥3 months old being raised for slaughter and mink being raised for pelt production||
|Poultry being raised for slaughter||
|All other species or classes of livestock and pet animals||
|* Includes lactating dairy cattle and hens laying eggs for human consumption
** Dry weight basis
Source: National Grain and Feed Association, 2011.
Dairy cattle may reduce feed intake when experiencing fumonisin toxicosis, resulting in reduced milk yield. Fumonisin may also result in liver damage and an increase in SCC (somatic cell count).
Diaz, D. The Mycotoxin Blue Book. 2005. 295–323. Nottingham, UK: Nottingham University Press.
National Grain and Feed Association. 2019. FDA Mycotoxin Regulatory Guidance: A Guide for Grain Elevators, Feed Manufacturers, Grain Processors, and Exporters. Washington, D.C.: National Grain and Feed Association.
Santin E. 2005. “Mould Growth and Mycotoxin Production.” In The Mycotoxin Blue Book, edited by D.E. Diaz, 225–234. Nottingham, UK: Nottingham University Press.
Publication date: Aug. 23, 2021
Other Publications in Guide to Mycotoxins Commonly Found in Animal Feeds
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