Between December and February we need to be thinking about how to approach our parasite control. At this time of year, encysted redworm, tapeworm and bots are ones to be particularly aware of.
Encysted Redworm
During the winter, small redworm goes through a dangerous parasitic stage in their lifecycle which it’s important to be aware of as they can have fatal consequences for horses.
At this stage the larvae of the worm burrow into the gut wall of the large intestine and become encysted where they can lie in a dormant state. They wait until conditions change, such as the shift from winter season to spring season, which triggers them to emerge en mass from the gut wall. This can cause a life-threatening bowel inflammation for the horse, known as colitis in which 90% of affected horses will die if not treated quickly.
For most horses encysted redworm is treated with a moxidectin wormer (such as Equest or Equest Pramox). The other alternative is a 5 day fenbendazole (Panacur Equine Guard) which is a good course for youngsters or horses struggling with maintaining condition.
Tapeworm
Equest Pramox wormer contains praziquantel which means it treats tapeworm as well as encysted redworm. With more than 77% of horses not needing to be treated from tapeworm, it’s recommended you test first to prevent unnecessary worming.
Bots
Bot larvae cannot be treated until they’re ingested and pass into the stomach of the horse. They can be treated in with your winter worming program - ivermectin and moxidectin are both effective chemicals, so worming for encysted redworm will also treat bot larvae at the same time.