Join Date: Nov 2010
Location: northeast Pennsylvania
My mare was rubbing her tail and it turned out to be pin-worms, I actually saw one come out to deposit it's eggs. When they deposit their eggs they leave a sticky glue like substance that apparently is itchy and annoying. If you are ever out to the barn later in the evening lift your guys tail and see if there is any sign of white residue. Pin worms can be hard to get rid of as the horse will reinfect itself by grazing(unless your pastures are cleaned very often). If not worms, needing a sheath cleaning is another good guess.