• Cause: lesions in wall of major arteries attributable to migratingStrongylus vulgarislarvae   Strongylus spp  .
• Signs: lesions in cranial mesenteric artery implicated in some cases of colic   Abdomen: pain - adult  .
• Diagnosis: history and clinical signs.
• Treatment: depends upon presentation.
• Prognosis: depends upon severity of condition. Severity of colic induced ranges from mild, recurrent, to severe, rapidly fatal. Aneurysms may rupture and lead to sudden death.

Presenting signs

• A localized inflammatory response in the artery is the most common presentation   →   embolic occlusion of larger or smaller mesenteric arteries   →   focal ischemia of jejunum, colon or cecum   →   colic.

• Aorto-iliac thrombosis is a vague hind limb lameness seen in males which may involve migrating strongyles in its etiology   Cardiovascular: aortoiliac thrombosis  .

Acute presentation

• Occasionally see ruptured aneurysms of cranial mesenteric artery with catastrophic blood loss into the abdomen and profound anemia.
• Or bleeding may be limited after rupture (eg hematoma confined within mesentery) and no effect on mucous membranes.
• Aortic rupture due to aneurysm occurs most commonly between right coronary artery and brachiocephalic trunk where parasitic arteritis involved and leads to sudden death   Aorta: rupture  .
• Pulmonary artery/renal artery rupture occasionally.

Age predisposition

• More commonly seen in horses <6 years old.

Cost considerations

• May be fatal, or require abdominal surgery.

Special risks

• Care must be taken with anesthesia as horse compromised due to blood loss/shock.