By Kimberly Cole, Extension Equine Specialist, Ohio State University
Internal parasites can cause a variety of problems in the horse ranging from a dull hair coat and unthriftiness to colic and even death. There are several species of internal parasites that can infect horses — most notably small and large strongyles, ascarids, tapeworms, pinworms and bots. Infected horses shed the parasite eggs in their manure, contaminating pastures, paddocks and pens. The eggs or larvae are ingested while the horse is grazing and mature within the horse’s digestive tract. Some parasites are able to migrate to other areas of the horse’s body, causing significant damage along the way.
In the past, traditional deworming recommendations were to treat horses with a different deworming product every 60-90 days. Research has shown that only about 20% of the horses in a herd shed the majority (> 80%) of parasites on a pasture. Treating horses with low numbers of parasites not only wastes money, but can promote resistance to dewormers.… Continue reading