Dead horses, cherry trees, caterpillars and cyanide

University of Kentucky Researchers and horse owners have been scrambling to find the cause of several hundred foal deaths in Kentucky this spring. The leading theory relates to cherry trees, though the scientific verdict is still out.

Cyanide, present in cherry leaves, is probably the strongest suspect. An especially long winter may have somehow played a part, because in 1981, a similar phenomenon occurred, following a similarly severe winter. However, investigators have also noted a high level of infestation of tent caterpillars this year, and this may be associated with the foal deaths as well.

Still not clear is how the toxins are being ingested by horses. However, the association between the foal deaths and cherry trees, cyanide and caterpillars seems strong.