16 April 2013

2 minute read

Fumonisins are produced by Fusarium verticillioides (formerly = F. moniliforme), F. proliferatum, and other Fusarium species. While these mycotoxins are found in other commodities, animal and human health problems related to these mycotoxins are almost exclusively associated with the consumption of contaminated maize or maize products.

Consumption of moldy maize has long been a recognized cause of equine leukoencephalomalacia (ELEM) and, over the years, experiments have demonstrated that F. verticillioides-contaminated feeds and fumonisin B₁ (FB₁) can induce ELEM. Similarly, F. verticillioides-contaminated feeds and FB₁ have been shown to be cardiotoxic and cause pulmonary edema in pigs, a syndrome termed porcine pulmonary edema. Cattle, with the exception of calves, lamb and goat kids are considerably less sensitive to fumonisins than horses, pigs, rabbits, or laboratory rodents.

Maize screenings are part of a basal diet for ruminants such as cattle and sheep in the USA, making fumonisin toxicity and excretion in milk a concern in ruminants.

Fumonisins are hepatoxic and nephrotoxic to calves. Major clinical signs of fumonisin poisoning in calves are lethargy and decreased appetite accompanied by serum biochemical and histologic evidence of hepatic damage.

The accumulation of sphinganine (Sa) and sphingosine (So) in the serum and urine is a useful biomarker for the exposure of fumonisins. These free sphingoid bases are toxic to most cells by affecting cell proliferation and inducing apoptosis or necrotic cell death and are associated with hepato- and nephrotoxic effects. Increased concentrations of Sa and So were found in theliver, kidney, lung, heart and skeletal muscle of calves fed diets contaminated with fumonisins.

Lambs and goat kids exposed to fumonisins expressed similar biochemical indices and histologic findings than calves and suffered from renal and mild hepatic toxicity. Similar to calves, goats also showed increased Sa and So concentrations in the liver, kidney and heart, which is clear evidence that all young ruminants with non-fully developed rumens and weak immune systems can be heavily affected by this group of mycotoxins.

Only accurate feeding in combination with continuous and effective mycotoxin risk management offer the keys to maintaining optimal health and improving the future performance of young ruminants affected by fumonisins.

April 2013