The goal of OTE’s parasite control program is twofold: to minimize worm burdens and decrease the rate at which parasites are developing resistance. OTE recommends, as a minimum precaution against resistance to current deworming products, that ALL horses get a fecal egg count (FEC) yearly on March 1.

New arrivals to a farm with unknown deworming history should be treated with Quest, followed the next day with Ivermectin. All other horses should bring deworming history including most recent FEC.

All dewormers should be administered according to weight (using a weight tape) when the horse has an empty mouth to ensure the medication is swallowed. For foals, and weak, debilitated, or pregnant horses, contact OTE for a consultation.

Low shedder deworming recommendations (less than 200 eggs per gram):

  • March 1—Fecal egg count
  • Moxidectin with praziquantel (Quest Plus)
  • November—Panacur Power Pac or Ivermectin with praziquantel (Equimax or Zimectrin Gold)

Medium and high shedders (greater than 200 eggs per gram):

  • March 1—Fecal egg count
    Moxidectin with praziquantel (Quest Plus)
  • June—Pyrantel Pamoate (Strongid Paste, Rotectin P, Equi-cide, Liqui-Care P, Tape Care Plus or Pyrantel Pamoate paste). Fecal egg count two weeks after deworming to measure dewormer effectiveness
  • September—Pyrantel Pamoate
  • December—Fecal egg count. Panacur Power Pac or Moxidectin with praziquantel


OTE recommends the following vaccinations:

Early spring

  • Intra-nasal or injectable influenza (flu)
  • Rhinopneumonitis (Rhino)
  • West Nile Virus (WNV)
  • Eastern/Western Encephalitis and Tetanus (EWT)
  • Potomac Horse Fever

Late summer

  • Intra-nasal or injectable influenza
  • Rhinopneumonitis
  • Rabies—given once annually in spring or late summer
  • West Nile Virus
  • Potomac Horse Fever
  • Eastern/Western Encephalitis

Pregnant mares and horses that travel to shows, events, etc. will need additional vaccines. Please call OTE for a consultation.

Botulism is an optional vaccine for horses that are fed round bales or reside in high incidence areas. It is also recommended for brood mares as it provides passive immunity to their foals.

Horses with no vaccination history require at least the basic vaccine set (EWT, WNV, Flu/Rhino, Rabies) followed by a second round given 3–4 weeks later.

Did you know?

A recent study that included over 1200 horses in 5 states has revealed that parasite resistance to commonly used dewormers is much more common that suspected and is growing worse. We have contributed to this problem by blindly deworming without first checking the worm burden in each horse, using dewomers with a greater frequency than is needed in many horses.

It will be years before the drug companies produce a “new” dewormer so we need to effectively use the ones we currently have.