Traditionally, deworming schedules involved treatments every two months, rotating the types of dewormers to minimize the risk of the parasites building up resistance to the chemicals. Some horses, however, can be kept perfectly healthy being dewormed only in the spring and fall.
Regular worm egg counts are necessary during the grazing season, which can be between March and September (weather dependent). Horses with single high worm egg counts, regular elevated counts or susceptible horses (very young or old) do then need treating.
Answer: While it is unlikely a horse will become ill or suffer harmful effects from being dewormed too often, in the long term, all horses’ health can be compromised by the development of parasite resistance to dewormers. … Thus, it doesn’t make sense to treat every horse with the same eight-week frequency.
Ivermectin and moxidectin are the best choices to control strongyle parasites. Pyrantel, fenbendazole and oxibendazole are good for treating ascarids in young horses. Ivermectin resistance is common in ascarids.
Symptoms of worm infections in horses
If you do not ACCURATELY know your horse or pony’s weight then by overdosing you will be speeding up the development of worm resistance and by under dosing you will be wasting your money on wormers as your horse or pony may still be suffering from worm infestation and damage.
Many of the data sheets for wormers, notably those that contain praziquantel, ivermectin or moxidectin, advise stabling for two – three days after worming. Equitape data sheet states that “in order to limit pasture excretion of the product and its metabolites, horses should remain stabled for two days after treatment”.
“(Non moxidectin, Non fenbendazole product) has the capacity to treat all common types of parasitic worms (including tapeworms) and bots.” “(Non moxidectin, Non fenbendazole product) has the best combined efficacy and the broadest spectrum of activity of any wormer.”
Treatment for Bots
Traditionally horses are treated for bots at the end of autumn, after a frost that kills the adult fly, and again at the beginning spring to rid the stomach of all the larvae. In the past the treatment was worse than the disease, with extremely toxic chemicals given via a stomach tube to the horse.
Horses that are very heavily infected with parasites may experience a bout of colic after you deworm them with paste wormer. It’s important to know that paste dewormer does not cause colic — but allowing parasites to build up in your horse’s system could cause an impaction of dead worms leaving the system.
While adverse events following vaccinations are typically rare, your veterinarian is trained to properly manage such an event. Typically, the vaccine manufacturer will not support the self-administration of equine vaccinations.17 мая 2017 г.
Ivermectin and moxidectin are effective against bots plus a wide range of internal parasites; these products are optimal for incorporation into your fall deworming program. Control of ascarids or roundworms (Parascaris equorum) isn’t determined by seasons, but by the horse’s age.
Horses over 15hh may require more than one syringe for the wormer to be effective. If you under dose your horse then the wormer will not work and you will be wasting your money.
Weight Assessment.Under 12hh Shetland, Dartmoor, Welsh A200kg – 320kg15hh to 16hh Arab, TB, ID, Welsh X400kg – 550kg16hh to 17hh TB, Warmblood470kg – 650kg