Equine Parasites

What can large stronglyes lead to in horses

Colic, diarrhea and/or chronic weight loss

Where are adult strongyles located

Within cecum and colon of infected horses

Can migrate throughout host tissues during developmental stages resulting in damage to various organs

What is part of the long strongyles

Strongylus vulgaris

Strongylus edentatus

Strongylus equinus

How does the larvae from strongylus vulgaris get around the body

Larvae penetrates submucosal arteries → migrate along endothelium to cecal and colic arteries → return to base of cranial mesenteric artery → return to intestines via arteries

What can strongylus vulgaris cause to the intestines

can cause thrombosis, inflammation, and infarction (tissue death due to inadequate blood supply) with subsequent necrosis of the intestine

How does strongylus edentatus get around

Larvae invade gut wall → penetrate blood vessels → migrate to liver via hepatic portal vein, larvae travel through the liver and return to the large intestine via mesentery

How does strongylus equinus get around

Larvae leave the intestine an migrate to the liver, then they migrate back to large intestine

What is the equine tapeworm also known as

Anoplocephala perfoliata

What is the equine tapeworm also known as

Anoplocephala perfoliata

What is also associated with anoplcephala perfoliata

Intussusceptions - where the intestines twist on themselves

Not known to be exactly the cause the intussusception b/c they may just be present in this region and observed during colic surgery

What is parascaris equorum also known as

Roundworms or ascarids

What is ascarids in horses

Disease in foals that result in ill thrift and poor weight gain

Can also result in significant disease from such a heavy burden of large worms resulting in intestinal impaction

Is ascarids a risk in adult horses

No - they develop an immunity to ascarids

What is cyathostomes also known as

Small strongyles - has a number of species (40+)

What are signs of cyathostomes?

Severe diarrhea in adult horses

Weight loss

Hypoproteinemia

Possible death

What is the condition that cyathostomes causes called

Larval cyathostomiasis

When does larval cyathostomiasis occur and why is that important

Occurs in late winter or spring

Is associated with simultaneous emergence of a large number of 4th stage larvae from intestinal mucosa

What is dictyocaulus arnfieldi also known as

Equine lung worm

Where is dictyocaulus arnfieldi infections seen in

Common in donkeys but rarely produce clinical signs

How do horses get the equine lung worm

Through contact with donkeys or their pasture that have this parasite

What are signs of the equine lung worm in a horse

Bronchial inflammation and chronic cough

Lung worm can grow upwards of 16cm