Deworming Recommendations in Longmont & Castle Rock, CO & serving clients in Berthoud, Erie & Elizabeth, CO

Parasite control involve many factors and we can help you design a program that best meets the needs of you an your horse(s).



  • Q: What types of "worms" might my horse have?
  • A: Mostly nematodes and insect larva.

  • Q: Are the "parasites" confined to my horse's stomach or intestines?
  • A: NO! In the normal course of their life cycle these parasites migrate throughout your horse's liver, lungs and arteries.

  • Q: If my horse has a negative "fecal exam" is he or she free of "worms"?
  • A: NO! It only means that here are not mature eggs laying parasites in your horse's intestine. It does not rule out migrating stages, encysted small strongyles or bots in your horse's stomach

  • Is regular "deworming" sure to eliminate all of my horse's parasites?
  • A: NO! Some - encysted strongyles and ascarids - are very hard to kill and resistance to anthelmentics (deworming medication) has been shown.

  • Q: How does my horse get infected?
  • A: Eggs are passing the manure of other (or your own) horse and can survive up to 10 years in the environment. Once contaminated, a pasture will remain infective for a long time. Once trick is to decontaminate a pasture is to graze cattle instead of horses for a year - cattle will ingest the parasites but the nematodes will not be able to complete their life cycle and new eggs will not be passed. Your foal can also get infected from his or her mother's milk, and you horse will get bot eggs of her or her own hair.

Things to Consider

Things to Consider

  • Regular fecal exams
  • Although a negative result down not guarantee your horse is parasite free, a positive result says a lot about the extent of any problem and the types of parasites you need to worry about. If re-infection rates are high, you nmight consider pasture management changes and/or daily deworming (Strongid).

  • Moxidectin (Quest) or Panacur Powerpac
  • Small strongyles encyst in the walls of your horse's intestine. Their presence cannot be determined by fecal exams, and they often emerge simultaneously in large numbers in the spring causing sever intestinal inflammation and possibly colic. Encysted strongyles are resistant to most dewormers. The two choices listed above have been shown to be effective.

  • Ivermectin and Praziquantil
  • Bots and tapeworms are not nematodes and will not be killed by most deowrmers. Use this combination in the fall to protect your horse against these parasites.

  • Benzimidazoles and Strongid
  • Very effective and safe. They are better than Ivermectin against some parasites and should be part of your deworming program. Rotation between multiple anthelmentics is always recommended to avoid resistance and to maximize effectiveness.