- Trichothecenes are a group of highly toxic mycotoxins produced by several species of Fusarium and certain other fungi
- These fungi affect grains in the field
- However, toxin production in increased by storage at cool temperature
- Therefore, natural poisonings are most common in areas with cooler climates
- Many different trichothecenes have been identified, but only a few appear to cause disease
- No well-defined clinical or pathological syndromes are associated with specific trichothecenes
- This is because there are many toxins, and more than one toxin usually exists in the same contaminated grain
- Besides, there is also difficulty of identifying the involved toxins in a clinical syndrome
- The best studied toxins include T-2 toxin DAS (diacetoxyscirpenol), vomitoxin, (DON or deoxynivalenol), and satratoxin
- T-2 toxin and DAS are highly toxic and cause necrosis of skin and mucous membranes (mouth, pharynx, oesophageus, rumen, stomach) on contact
- These toxins are potent inhibitors of protein synthesis, which accounts for their cytotoxicity
- Ingestion of vomitoxin leads to anorexia and vomiting, especially in pigs, but most species are susceptible
- It acts on central nervous system receptors without producing morphological lesions
- Rapid recovery occurs following removal of the toxin from the diet
- Various syndromes are believed to be caused by trichothecene toxicity, especially in cattle, pigs, horses and poultry
- Clinical signs include oral ulceration, anorexia, vomiting, diarrhoea, haemorrhage, leukopenia, jaundice and incoordination
- Specific lesions include necrosis of all lymphoid organs, bone marrow and gastrointestinal epithelium
- There may also be necrosis in the liver, kidney, heart and pancreas
- In cattle, a condition called “Mouldy corn poisoning” is believed to result from T-2 toxin
- This disorder is characterized by extensive haemorrhage
- Satratoxin (stachybotryotoxin) a trichothecene produced by Stachybotrys sp. and other fungi, on ingestion, causes a disease known as “Stachybotryotoxicosis”
- It has occurred in hours, cattle, sheep, pigs, poultry and humans in the USSR, Hungary, Czechoslovakia, Finland, France and South Africa following consumption of mouldy straw or hay
- The disease and lesions are similar to those to T-2 toxin
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