Septic fibrinous pericarditis in 4 horses / forest tent caterpillars

This serves as a reminder to keep caterpillar nests out of your horse pastures.
DrO

Can Vet J. 2020 Jul;61(7):724-730.
Septic fibrinous pericarditis in 4 horses in Saskatchewan following an outbreak of forest tent caterpillars in 2017.
Chapuis RJJ1, Ragno VM1, Ariza CA1, Movasseghi AR1, Sayi S1, Uehlinger FD1, Montgomery JB1.

Author information:
1. Clinical Sciences, Ross University School of Veterinary Medicine, PO Box 334, Basseterre, St. Kitts, West Indies (Chapuis); Large Animal Clinical Sciences (Chapuis, Ragno, Ariza, Uehlinger, Montgomery) and Prairie Diagnostic Services (Sayi), Western College of Veterinary Medicine, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4; Washington State University, College of Veterinary Medicine, Veterinary Teaching Hospital, 205 Ott Road Pullman, Washington 99164-7060, USA (Ariza); Charles River Laboratories, 445 Boulevard Armand-Frappier, Laval, Quebec H7V 4B3 (Movasseghi).
Abstract

In the summer of 2017, 4 horses were diagnosed with septic fibrinous pericarditis at the Western College of Veterinary Medicine, Saskatoon. This case series occurred after a significant outbreak of forest tent caterpillars (Malacosoma disstria) in the province during that spring. Three horses were immediately euthanized, and treatment was attempted in 1 mare. This is the first case series of pericarditis possibly associated with the ingestion of forest tent caterpillars to be reported in western Canada. Although cause-effect is not proven, it is prudent to prevent the ingestion of caterpillars by horses. Key clinical message: Septic fibrinous pericarditis, a rare condition in horses, has previously been linked to outbreaks of eastern tent caterpillars. A similar link might exist in this case series.