ABSTRACT
The 290,000 named species of beetles distributed worldwide comprise 40% of named insects. Blister beetles, Epicauta spp., are in the family Meloidae, order Choleoptera, class Insecta. Numerous species of the genus have been implicated in poisoning of horses and livestock in North America. The key factors in a differential diagnosis of blister beetle poisoning in a horse are: finding the beetles in hay being fed, clinical signs of colic and hematuria, an elevated packed cell volume, and hypocalcemia and hypomagnesemia. In areas where blister beetle poisoning is known to occur, hay should be inspected by the owner or the caretaker as the hay is fed. Unfortunately, because alfalfa hay may be transported thousands of miles before ultimate consumption, one cannot depend on the absence of swarming blister beetles in the local area.
