By Tracy Turner Fall frost is an annual concern for livestock
producers because of the potential for prussic acid poisoning,
but the potential for toxicity in livestock is of wider concern
this year because of drought, an Ohio State University Extension
forage specialist says. The drought of 2012 has been one of the
worst on record, leaving many livestock producers short on hay
and silage supplies. The lack of substantial rainfall, extreme
heat and dryness left many producers looking for any alternative
forages they could plant to make up for the shortages, Mark Sulc
said. As a result, some chose to grow sudangrass, sudangrass
hybrids, forage sorghums or sorghum-sudangrass crosses, which
can produce excellent forage yields in a short time but are
capable of becoming toxic to livestock after a frost event, Sulc
said. These species contain compounds called cyanogenic
glucosides that convert quickly to prussic acid in freeze-
damaged plant tissue. "Animals can die within minutes if they
consume forages such as th