How to treat worms in horses requires a combination of pasture management and good deworming program. The following are general recommendations for how to treat worms in horses.
Firstly removal of manure from small pastures should occur twice weekly. In addition larger pastures frequent mowing/harrowing and animal rotation. Horses should be removed from pastures for a minimum of 6-8 weeks and adding sheep or cattle helps to decrease parasite numbers.
The Faecal Egg Count (FEC)
A Fecal Egg count (FEC) is the best way to measure the number of strongyly or tapeworms per gram of manure. A FEC testing kit will provide you with an accurate measure and therefore help determine which dewormers to use.
Choosing the correct dewormer should be discussed with your vet. Fenbendazole is recommended for control of strongyles, tapeworms and roundworms in mature horses. Best to perform treatment nearing the end of the grazing season when worms are at their peak.
Treatment of bots is also essential in your worm management program. Ivermectin is the best wormer for bots. In addition the manual removal of the yellow bot eggs from the horse’s coat. The broadspectrum Ivermectin/Praziquantel combination is the best weapon for treating tapeworms.
Deworming foals and weanlings
During the first year of life a foal should be dewormed at least 4 times. First at 2-3 months to ensure against large roundworms. Second worming should be just before weaning ~6 months. At weaning, a FEC is a good idea to determine which worms need to be treated against. Third and fourth treatments should be between 9-12 months old and should target strongyles. Tapeworm treatment should be included around this time as well.
Remember that each horse and region is unique. Please consult with your local veterinarian for a more individualised treatment program for your horse.