VPT 421: Veterinary Toxicology (2+0)

AFLATOXIN POISONING

• Aflatoxins are the toxic metabolites of the molds of Aspergillus flavus and Aspergillus parasiticus.
• They are normally present in stored feedstuff.
• They grow rapidly and become toxic in grains and feed stored under aerobic conditions when the moisture is more than 15% and temperature is 24 – 25 degrees C.
• Peanuts, cottonseed meal and cake are affected frequently.
• Corn ears with shortened husks maturing in upward position appear to be more susceptible. Although at least 13 aflatoxins have been identified , aflatoxin B₁, B₂, G₁ and G₂ are the major types. B₁ and B₂ produce blue florescence while G₁ and G₂ produce green fluorescence.
• Of these metabolites, AFB₁ is of importance because of toxicity and concentration in moldy feeds. The order of toxicity is B₁>G₁>B₂>G₂ .
• Metabolites of B₁ and B₂ are excreted in milk and are termed as M₁ and M_{2 .}