Parasites
A permanent nuisance and threat
All horses are affected by parasites. Some parasites, such as flies, are just a nuisance. Others cause severe impairment of well being or even fatal diseases. The greatest threat comes from endoparasites: mainly worms and fly larvae.
Flies are a permanent nuisance
Flies are, strictly speaking, not parasites, but they can be mentioned in this context because they may become a nightmare for every horse. They can be distributed in great numbers all over the body and are particularly annoying for the horse at the eyes and nostrils. There is not very much to be done about this. However, horses defend themselves using their long-haired mane and tail so these should not be cut off in times when flies are abundant.
Endoparasites are a threat for horses
No horse will be free of internal parasites such as worms and fly larvae. They feed on blood, tissue, and nutrients in the gastrointestinal tract. Depending on the parasite species, horses may develop anemia, verminous colic, various skin problems or allergic reactions and are generally impaired in their well being. Internal parasite infections can particularly impair the development of young horses and can cause death in adult horses.
Endoparasite control
The most obvious routines for parasite control are appropriate pasture selection and reliable stable management. However, a policy of routine deworming treatments is advisable to prevent the impairment of your horse's health. Deworming treatments are best carried out on the pasture at four-week intervals from April to August. This way no eggs are passed out in spring and summer, thus preventing contamination of the pasture at this time. It is strongly recommended that all horses are dewormed at the same time.
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