Source: Wisconsin Department of Agriculture, Trade and Consumer Protection
The finding that moldy sweet potatoes led to the death of 200 steers on a Portage County farm has prompted Wisconsin State Veterinarian Dr. Robert Ehlenfeldt to remind producers to be well aware of exactly what goes into their livestock feed rations.
“This was a very unfortunate incident,” Ehlenfeldt said. “I’m glad to say that the producer involved followed the right course, testing at his own expense to find out what the cause was. So, if any good can come out of it, it may be that he’s helped other livestock owners benefit from his experience and avoid the same kind of loss he suffered.”
The case had been widely reported in the media, because it seemed mysterious to laymen; a large number of cattle died in a brief time, and laboratory tests showed pneumonia, but did not find any bacterial or viral infection. But to veterinarians and pathologists, the feed ration became suspect almost immediately.
The animals were being fed byproducts from vegetable processing, including sweet potatoes, some of which were moldy. 4-ipomeanol, a toxin produced by mold on sweet potatoes, is highly poisonous to cattle and causes pneumonia – fluid in the lungs. The Wisconsin Veterinary Diagnostic Laboratory announced Friday that test results had confirmed the presence of this toxin in the sweet potatoes fed to the cattle.
“Byproduct use in livestock feed is appropriate and can be beneficial, but you need to know exactly what you’re putting into rations. When you’re feeding byproducts, you need to be thinking about what the nutritional value is, checking the quality, looking for mold and other problems,” Ehlenfeldt said. “If you’re mixing your own rations from commercial feeds, you need to be reading and following the labels. Understand the risks and the advantages, for the good of the animals and for your own bottom line.”