|College of Agriculture|
April 7, 2003
Frost and Horse Pasture
Jimmy C. Henning
Assistant Director for Cooperative Extension
Agriculture and Natural Resources
Former Extension Forage Specialist
University of Kentucky
Frost events this spring should have little impact on cool season grass or clover composition and therefore pose no significant forage concern for pregnant mares.
The pasture monitoring program in 2002 found little to no change in mineral content or mycotoxin content resulting from frosts. The potential of white clover to liberate cyanide was elevated slightly during the frost events in 2002, but this dissipated by mid-morning. Further, cyanide was proven to be unrelated to MRLS by UK research. In addition, horses have good tolerance to cyanide that might arise in their diet from pasture sources, even greater than cattle.
Therefore, there is no forage basis for making significant management changes for pregnant mares due to frost effects on pastures.