title: Morphometric Properties of the Thoracic Aorta of Warmblood and Friesian Horses with and without Aortic Rupture.
abstract: Rupture of the aorta is much more common in Friesians compared with other breeds of horse. Rupture always occurs adjacent to the scar of the ligamentum arteriosum. Previous histological examination of ruptured aortic walls suggested the presence of an underlying connective tissue disorder. Therefore, the aim of the present study was to compare the structural characteristics of the tunica media of the mid-thoracic aorta, distant to the lesion, in warmblood and Friesian horses with and without thoracic aortic rupture. In unaffected Friesian horses, the thickness of the tunica media, as well as the percentage area comprised of collagen type I, were significantly higher compared with the warmblood horses, supporting the hypothesis of a primary collagen disorder in the Friesian horse breed. However, in the tunica media of the affected Friesian horses there was no significant wall thickening. Moreover, the percentage area comprised of elastin was significantly lower, while the percentage area comprised of smooth muscle was higher, compared with unaffected Friesian and warmblood horses. These lesions are suggestive of an additional mild elastin deficiency with compensatory smooth muscle cell hypertrophy in affected Friesians.
authors.affiliation: Laboratory of Veterinary Pathology, Department of Pathology, Bacteriology and Poultry Diseases, Ghent University, Merelbeke, Belgium. Electronic address: veronique.saey@ugent.be.
authors.forename: V
authors.initials: V
authors.lastname: Saey
authors.affiliation: Department of Pathobiology, Faculty of Veterinary Medicine, Utrecht University, The Netherlands.
authors.forename: M
authors.initials: M
authors.lastname: Ploeg
authors.affiliation: Department of Comparative Physiology and Biometrics, Belgium.
authors.forename: C
authors.initials: C
authors.lastname: Delesalle
authors.affiliation: Department of Large Animal Internal Medicine, Ghent University, Merelbeke, Belgium.
authors.forename: G
authors.initials: G
authors.lastname: van Loon
authors.affiliation: Department of Pathobiology, Faculty of Veterinary Medicine, Utrecht University, The Netherlands.
authors.forename: A
authors.initials: A
authors.lastname: Gröne
authors.affiliation: Laboratory of Veterinary Pathology, Department of Pathology, Bacteriology and Poultry Diseases, Ghent University, Merelbeke, Belgium.
authors.forename: R
authors.initials: R
authors.lastname: Ducatelle
authors.affiliation: Department of Comparative Physiology and Biometrics, Belgium.
authors.forename: L
authors.initials: L
authors.lastname: Duchateau
authors.affiliation: Laboratory of Veterinary Pathology, Department of Pathology, Bacteriology and Poultry Diseases, Ghent University, Merelbeke, Belgium.
authors.forename: K
authors.initials: K
authors.lastname: Chiers
mesh_terms: D000818:Animals; D001013:Aorta, Thoracic / Q000473:pathology*; D001019:Aortic Rupture / Q000473:pathology / Q000662:veterinary*; D006734:Horse Diseases / Q000473:pathology*; D006736:Horses
keywords: aorta; horse; morphometry; rupture