Blood supply and arteriography of the pelvic limb of the Southern caracara (Caracara plancus) and great egret (Ardea alba)

Abstract

The aim of this study was to compare the arterial vascularization of the pelvic limb between southern caracara (Caracara plancus) and great egret (Ardea alba) by dissection and radiographic examinations. Five specimens of caracaras (three males and two females), and seven great egrets (five males and two females) were used. Barium sulphate and latex suspension were injected into the left ventricle of the birds. The radiographs were taken with the pelvic limbs in the ventrodorsal, dorsoplantar, mediolateral and lateromedial recumbency. Thereafter, the material was fixed in a 10% solution of formaldehyde and dissected. The pelvic limb received its arterial supply from two main vessels, the ischiatic and external iliac arteries. The ischiatic artery presented to be the principal artery of pelvic limb in the caracara and great egret. Several branches arised from the ischiatic and external iliac arteries were described. No gender differences were observed in both species. The caracara and great egret showed arteries similar to those reported for the ostrich and domestic fowl. According to the results of this study, it is suggested that the caracara has a pelvic limb with more arterial branches and larger arterial diameter than the great egret, which is probably related to the specific behaviour of these birds, since the caracara is a bird that exercise more their pelvic limbs to capture its prey when compared with the great egret.