Dynamic Assessment through Histological Study of Wall Development in the Aortic Arch and Brachycephalic Trunks in Ross 308 Broiler Chickens

The number of studies about specific arterial structure in avian species is remarkably lower than those carried out in mammals, thus, this study aims to describe the microscopic structure and the development of the aortic arch and the 2 brachycephalic trunks in Ross 308 broiler chickens aged 20 and 30 days, respectively. During necropsy, transverse fragments were harvested from the aortic arch and the two brachiocephalic trunks (right and left), fixed in formalin, embedding in paraffin and stained with Verhoeff trichrome method. The histological slides were examined under optical microscope and the wall thickness and the number of elastic lamellae were determined. In Ross 308 broiler chickens aged 20 and 30 days, respectively, the aortic arch and the brachycephalic trunks are elastic-muscular transitional arteries. Between 20-30 days of life, the aortic arch wall thickness increase by approximately 18% and the brachiocephalic trunks by approximately 85%. The elastic lamellas present in the vascular wall structure are thicker in the brachiocephalic trunks than in the aortic arch in both 20-day-old and 30-day-old chicks.