Deworming Your Horse


Below is an example of common deworming protocols that we often recommend for our patients. However, our doctors will work with you to customize a preventative care program that fits your individual horse at each appointment, particularly for foals, pregnant mares, or horses with other medical conditions or illnesses.

Adult Horses

  • September: Fecal egg counts (FECs) should be performed on all horses that have not received deworming in the previous 12 weeks (16 weeks for Moxidectin). Based on the results of the FEC, horses will be classified as low, medium, or high shedders. Deworm according to FEC as follows:

    • Low and Medium Shedders: deworm with Ivermectin

    • High Shedders: deworm with Ivermectin or Moxidectin

  • November: Deworm horses that were medium and high shedders with Oxibendizole or Pyrantel.

  • January: FECs should be performed on all horses, then deworm ALL horses with Ivermectin/Praziquantel or Moxidectin/Praziquantel.

  • April: Treat January high shedders with a 5 day double dose of Fenbendazole (10mg/kg).


  • Deworm every two months, starting at 2 months of age, and continue until 18 months of age. Rotate with Fenbendazole (10mg/kg) and Pyrantel. Beginning at 6 months of age, include Ivermectin in the rotation.

Key Points

  1. FECs should be performed at least twice yearly on all horses (beginning of fall and mid-to-late winter).

  2. Ivermectin should be given twice yearly, regardless of FEC results.

  3. Do NOT use Moxidectin on foals or broodmares. A weight tape must be used for accurate dosing in adult horses.

  4. Small Strongyle treatment should be given as needed.

  5. Times and frequencies may vary depending on environmental conditions (Ex. stall vs pasture, temperatures, moisture, horse concentration, manure management, etc.)

Fecal Samples

  • Samples should be 1-2 fresh fecal balls collected from the center of a manure pile (<2hrs old) and free of dirt or bedding. Samples should be placed in a zip-lock bag with all air removed and labeled with the horse's name, date of collection, and time of collection.

  • Samples must be kept cool. Place it in an ice chest to bring to the clinic as soon as possible.

  • If you have submitted a fecal sample, we will call you with the results within the next few business days. If you do not receive the results within one week, please call our office at (209) 524-9191.

Roya1234 none 8:00 AM - 5:00 PM 8:00 AM - 5:00 PM 8:00 AM - 5:00 PM 8:00 AM - 5:00 PM 8:00 AM - 5:00 PM 8:00 AM - 12:00 PM Closed veterinarian,3,,, #,-120.837257,15z/data=!4m5!3m4!1s0x0:0x2173ad6a01a882dc!8m2!3d37.63659!4d-120.837257