Anoplocephala and Paranoplocephala
The tapeworms Anoplocephala perfoliata, A. magna and Paranoplocephala mamillana occur in horses around the world.
Chorioptes equi
The surface mite Chorioptes occurs on horses and other equids around the world.
Cryptosporidium species - horses
The surface mite Chorioptes occurs on horses and other equids around the world.
Culicoides species — biting midges or no-see-ums
Midges of the genus Culicoides occur around the world, including in Canada. Adult females must blood-feed on animals, producing painful bites prior to laying eggs.
Cyathostomins
The cyathostomins are a large group of genera and species of closely related nematodes that live as adults in the large intestine of horses around the world, including Canada.
Dermacentor albipictus
Dermacentor albipictus (the winter tick or moose tick) is a large reddish-brown to gray-brown tick. In Canada, D. albipictus is found in all provinces and territories, appearing as far north as the southern Yukon.
Dermacentor andersoni -- horses
Dermacentor andersoni is a large reddish-brown to gray-brown tick. In Canada, it is found from central Saskatchewan and west through Alberta and into British Columbia.
Dermacentor variabilis: American dog tick
Dermacentor variabalis is a large reddish-brown to gray-brown tick. In Canada, D. variabilis is found from eastern Saskatchewan and east through to Nova Scotia, primarily in the southern portions of each province.
Dictyocaulus arnfieldi
The lung nematode Dictyocaulus arnfieldi occurs in horses and other equids in many parts of the world, including rarely in Canada.
Eimeria leuckarti
Eimeria leuckarti is a coccidian protozoan that infects horses around the world, including in Canada.
Eutrombicula species
Trombiculid mites are free-living but their larval stages can infest a range of mammals, birds and people, causing sometimes severe skin lesions characterised by intense pruritus.
Gasterophilus
Bot flies of the genus Gasterophilus infest horses around the world, including Canada.
Giardia species-horses
Little is known of the occurrence or clinical significance of Giardia species in horses.
Habronema species and Draschia species
Habronema and Draschia are small nematodes that as adults inhabit the stomach of horses.
Lice: Chewing: Werneckiella (Damalinia) equi; Sucking: Haematopinus asini
Horses around the world, including in Canada, are infested with sucking (Haematopinus asini) and/or chewing (Wernekiella (Damalinia) equi) lice.
Onchocerca cervicalis
The nematode Onchocerca cervicalis occurs in horses in many regions of the world where suitable midge intermediate hosts (Culicoides species) are also present.
Otobius megnini
The Argasid (soft) tick Otobius megnini, the spinose ear tick, infects cattle, sheep, dogs, horses and occasionally people in and North America, including Canada, as well as South America, India, and South Africa.
Oxyuris equi
The pinworm nematode Oxyuris equi occurs in horses around the world, including Canada.
Parascaris equorum
The ascarid nematode Parascaris equorum occurs in horses around the world, including Canada.
Piroplasms (Babesia caballi and Theileria (Babesia) equi)
Babesia and Theileria are the two genera comprising the protozoan Phyllum Piroplasmorida.
Sarcocystis neurona
Sarcocystis neurona is an intracellular, apicomplexan protozoan that occurs in horses and other hosts in the Americas.
Sarcocystis species-pigs
Species of the intracellular, apicomplexan protozoan Sarcocystis occur in mammals, reptiles and birds around the world, including in Canada.
Setaria species
Nematodes of the genus Setaria infect cattle, sheep, sometimes other domestic animal hosts, and many free-ranging ungulates around the world, including in Canada.
Setaria species — pigs
Nematodes of the genus Setaria infect cattle, sheep, sometimes other domestic animal hosts, and many free-ranging ungulates around the world, including in Canada.
Simulium species — black flies or buffalo gnats
Flies of the genus Simulium (blackflies or buffalo gnats) occur in almost all parts of the world, including Canada.
Stomoxys calcitrans — stable fly
The stable fly Stomoxys calcitrans occurs around the world. The life cycle involves egg laying in faeces or decaying and damp organic material, for example straw bedding.
Strongyloides westeri
The nematode Strongyloides westeri occurs in horses around the world, including Canada.
Strongylus edentatus
The nematode Strongylus edentatus occurs in horses around the world, including Canada.
Strongylus equinus
The nematode Strongylus equinus occurs in horses around the world, including Canada.
Strongylus vulgaris
The nematode Strongylus vulgaris occurs in horses around the world, including Canada.
Tabanids: Tabanus species - Horse Flies; Chrysops species – Deer Flies; Haematopota species - Clegs
The various genera and species of tabanids (horse flies, deer flies and clegs) occur around the world, including in Canada.
Toxoplasma gondii
Toxoplasma gondii is a zoonotic intracellular apicomplexan protozoan parasite of mammals and birds that occurs around the world, including in Canada.
Toxoplasma gondii
Toxoplasma gondii is a zoonotic intracellular apicomplexan protozoan parasite of mammals and birds that occurs around the world, including in Canada.
Toxoplasma gondii — pigs
Toxoplasma gondii is a zoonotic intracellular apicomplexan protozoan parasite of mammals and birds that occurs around the world, including in Canada.