Deworming Horses: Deworming Rotation Schedule
Parasites do not want to kill your horse; your horse is the dinner plate. Parasites do not mind robbing the best nutrition from your horse. Deworming a horse is good preventative medicine! With all the options available, you need to determine which dewormers and schedule are best for your horse.
Your horse’s job and living conditions will dictate the number of times you need to deworm. If your horse is what you call a "backyard horse," then a minimal amount of deworming is needed, as long as you rotate with different types of dewormers. For the horse that stays home, you will probably only need to deworm in the spring, summer, and fall. This will be sufficient enough to prevent from feeding parasites and prevent colic, both good reasons to deworm. Show horses that travel and stabled horses may need dewormer every other month to prevent parasite issues.
If you are behind in deworming, start deworming twice with two different dewormers one week apart and that will catch you up. Follow as needed with rotational deworming.
If you use the same dewormer repeatedly, the parasites either become extinct or they learn to eat the dewormer. Parasites have been around since dinosaurs, so chances are they are not extinct. You need to rotate dewormer families between Fenbendazole (Panacur® Equine Dewormer
), Pyrantel (Strongid® T
) and Ivermectin to prevent resistance issues. Deworming is an expensive process, so the last thing you want is one that doesn't work for your horse. Rotate your dewormer. Try Fenbendazole in the hot and cold time of year and Ivermectin with Praziquantel (EquiMAX®
) in the spring to get tapes and bots. Pyrantel can be used in the fall, and if you are in a high tapeworm area, be sure to repeat the Praziquantel.
RECOMMENDED DEWORMING ROTATION SCHEDULE
Deworm 4 times a year for most horses and 6 times a year for highly-exposed horses such as show horses.
In addition, manure management will also help keep the parasite numbers low on your pasture. Parasite eggs are passed in the stool and mature in our pastures. The larvae get into dew droplets on the grass and are grazed down by your horse. Rotate horses between pastures and drag pastures to break up manure, exposing parasites to the sun so they die. Compost all manure before spreading on pastures. Composting will kill the parasite eggs before they are spread on the soil to be picked up again by your horse. Never spread raw manure on pastures. The goal is to decrease the larva load on the pasture your horse grazes!
Rotating dewormers at the correct time and pasture management will prevent parasites from being an issue for your horse.
If you need help, call us at 1-800-786-4751.
Don Bramlage, DVM, Director of Veterinary Services at Revival Animal Health
The materials, information and answers provided through this website are not intended to replace the medical advice or services of your personal veterinarian or other pet health care professional. Consult your own veterinarian for answers to specific medical questions, including diagnosis, treatment, therapy or medical