Diagnosis > Equine

Ochratoxins are important storage toxins. First discovered in 1965 by Van der Merwe et al. they are produced by different fungi and are prevalent in temperate as well as in tropical regions.  Ochratoxin A is the most important of the ochratoxins and has been found in oats, barley, maize and wheat with a moisture content of around 16%. Barley appears to be particularly prone to contamination. Aspergillus and Penicillium species of fungi are responsible for ochratoxins.

The primary effect of ochratoxin A in horses is nephrotoxicity and in acute cases death can occur due to acute renal failure. In addition, ochratoxin A is hepatotoxic, carcinogenic, a potent teratogen and suppresses the immune system.

Clinical signs of ochratoxin toxicity include:

• Reduced feed intake
• Reduced growth rate
• Poor performance
• Reduced feed conversion efficiency
• Enhanced susceptibility to viral infections
• Death due to acute renal failure.

Intervention level

In the absence of information for horses the proposed level of intervention is 50ppb as used in pig production as this takes into account possible cumulative and/or synergistic effects of other mycotoxins that may affect the immune system.