Skip to main content

Trichothecenes

Trichothecenes are produced by several common molds including species in the genera Acremonium (Cephalosporium), Cylindrocarpon, Dendrodochium, Myrothecium, Trichoderma, Trichothecium, and most numerously in Fusarium. Trichothecenes are composed of a tetracyclic sesquiterpene skeleton containing a six-membered oxane ring, a stable epoxide group in positions 12 and 13 and a 9,10 olefinic bond. They have been classified into four groups. Fusarium spp. contain several well known trichothecenes including two highly toxic members of group A, diacetoxyscirpenol (DAS) and T-2 toxin, and toxins in group B including deoxynivalenol (DON) and nivalenol. DON is the most common but leat toxic of these. Trichothecenes are strong inhibitors of protein synthesis in mammalian cells. However, DOM received its common name, vomitoxin, from the vomiting that generally accompanies trichothecene poisoning. (D'Mello, et.al., 1991)

DON resulted in feed refusal in swine. In lambs, consumption of a wheat diet containing DON at 15.6 mg/kg of BW for 28 d did not alter feed consumption, weight gain, or feed efficiency. Oral administration of DON showed that it was rapidly passed essentially unchanged (95%) and excreted primarily in urine. Incubation of DON with ruminal microorganisms in vitro for 48 h resulted in partial conversion to deepoxy DON. These results indicate that the impact of DON on ruminants is lower than initially suspected. DON caused no organ damages to animals. Extremely low amounts of DON(<4ng/ml) were transmitted to milk after a single oral dose of 920 mg to a dairy cow. (Diekman and Green, 1992)

The FDA issued an "advisory" to federal and state officials recommending a level of concern for DON of 2 micrograms of DON/ gm for wheat entering the milling process, 1 microgram/ gm in finished wheat products for human consumption, and 4 microgram/ gm for wheat and wheat milling by-products used in animal feed. (Wood, 1992)

[Return to list of toxicants]

References

Cheeke, P.R., (1995) Endogenous Toxins and Mycotoxins in Forage Grasses and Their Effects on Livestock. J. Anim. Sci. 73:909-918.


Cheeke, P.R. and Shull, L.R. (1985) Mycotoxins (Chap. 12). In: Natural toxicants in feeds and poisonous plants. AVI. pp393-477.

Chu, S.F., (1992) Recent Progress on Analytical Techniques for Mycotoxins in Feedstuffs. J. Anim. Sci. 70:3950-3963.


Diekman, M.A. and Green, M.L., (1992) Mycotoxins and Reproduction in Domestic Livestock. J. Anim. Sci. 70:1615-1627.


Flannigan, Brian, (1991) Mycotoxins (Chap. 10). In: Toxic Substances in Crop Plants. The Royal Society of Chemists.pp226-257.

Price, W.D., Lovell, R.A. and McChesney, D.G., (1993) Naturally Occurring Toxins in Feedstuffs: Center for Veterinary Medicine Perspective. J. Anim. Sci. 71:2556-2562.


Richard, J.L., Bennett, G.A., Ross, P.F. and Nelson, P.E., (1993) Analysis of Naturally Occurring Mycotoxins in Feedstuffs and Food. J. Anim. Sci. 71:2563-2574.


Spainhour, C.B. and Posey, D. (1992) Mycotoxins: A Silent Enemy. Large Animal Veterinarian. Nov./Dec. Page 20-25.

Thompson, Larry. (1996) Lecture for PLPA 652 ('Mycotoxins')

Wood, G.E., (1992) Mycotoxins in Foods and Feeds in the United States. J. Anim. Sci. 70:3941-3949.


Wren, G., (1994) Blaming Mycotoxins Can Be A Risky Venture. Bovine Veterinarian. Nov. Page 4 -10.

More information on FDA recommendationsThe poisonous plant database