Q: How can I protect my horse from ticks?
A: Given horse skin can be quite sensitive, it is best to stay ON LABEL! There are some oral pastes like ivermectin and moxidectin, which will produce blood titers high enough to kill feeding ticks. Pour- or spray-ons for horses are more difficult to recommend. If one were worried about ticks on horses, keep them out of areas where ticks will be abundant. Such areas include densely vegetated (tall grass, shrubby ground) habitats. Dry paddocks and grazed pastures inside fences should not be a problem. Before riding into such areas, dose legs with a permethrin-based product (again, only if formulated for use on horses), which will repel ticks before they get attached.
Roger Moon, PhD, University of Minnesota