The brain arterial circuit in swine (Sus scrofa domesticus Linnaeus, 1758), behaviour and formation

Abstract

Forty neonatal pigs were usec both (male and female) in the amount of 20 each in order to study the vascular arrangement that is placed in the region of the mammillary corpus, the tuber cinereous, the hypophysis and the optical chiasma in the encephalon basis. All the animals were from Santa Terezinha Farm sited in Uberlândia. 30 of them had their arteries injected with Neoprene Latex "400" colored with a specific pigment and then fixed with 15% formaldehyde solution. After that, they were dissected. The 10 left were injected with colored vinyl acetate followed by corrosion with 30% sulfuric acid solution. The pieces were washed afterward in tap water. The results showed that the arterial circuit is a formation from the division of encephalon carotid artery in both hemisphere in its rostral and caudal terminal branches. The appearance of the arterial circuit is rostrally like a small medial concavity arc (left right halves). Caudally it shows morphologic characteristics as a polygon picture - a hexagonal caudal half - (53.3%) and the left, like a heart picture (46.7%). The circuit is rostrally closed by the constant presence of the rostral communicant artery in all the preparations and caudally by the presence of left and right terminal branches of basilar artery. Besides the presence of left and right terminal branches of basilar artery, in 10% of the pieces the arterial circuit showed at the usual place of bifurcation, two little anastomosis.