Pony: Cranial mesenteric artery: Thrombosis and severe, chronic, granulomatous arteritis with intralesional nematode larvae.
Pony, 12 months.
Diagnosis: Cranial mesenteric artery: Thrombosis and severe, chronic, granulomatous arteritis with intralesional nematode larvae; arrow indicates the longitudinal axis of the aorta
Description: The cranial mesenteric artery and her radiating branches are thrombosized and vascular walls are thickened by chronic, granulomatous inflammation. Intraluminal are several nematode larvae.
Comments: Clinical symptoms included emaciation and terminal recumbency. Necropsy confirmed cachexia with serous atrophy of adipose tissue in the bone marrow and the coronary grooves. Dominant findings in the digestive tract were a multifocal ulcerative gastritis and severe infestation by equine bots. Additionally, large numbers of intestinal endoparasites (large and small strongyles) were present. As a consequence the liver showed a multifocal pyogranulomatous hepatitis due to migrating larval stages. Histology identified the larval stages in the cranial mesenteric artery as strongyles by typical criteria like a smooth cuticle, platymyarian-meromyarian musculature, prominent lateral cords, a pseudocoelom, and a large, central intestine (consistent with Strongylus vulgaris).
Picture by: Petra Wittschen, Department of Veterinary Pathology, Freie Universität Berlin, Germany
Author: Olivia Kershaw, Department of Veterinary Pathology, Freie Universität Berlin, Germany