Branches of the external carotid artery in the red kangaroo and the red-necked Wallaby

Background The red kangaroo and the red-necked wallaby are Australian marsupial species frequently kept in zoological gardens. As exotic animal veterinary medicine develops, there is a growing need to expand fundamental anatomical knowledge of these species. Although cerebral vascularisation has been described, data on the arterial supply of the facial region, which is relevant to surgery and dentistry, remain limited. The aim of this study was to determine and compare the pattern of arterial vascularisation of the face in both species. The study included 18 adult red kangaroos and 35 adult red-necked wallabies obtained from zoological gardens. Three complementary methods were used: latex injection into the common carotid arteries, corrosion casting with acrylic resin, and angio-CT following administration of barium sulphate. Results In both species, the head was supplied by paired common carotid arteries, which divided at the level of the C1 vertebra into the internal and external carotid arteries. The main branches of the external carotid artery included the lingual, facial, caudal auricular, and superficial temporal arteries. The maxillary artery gave rise to branches supplying the masticatory muscles, dura mater, oral cavity, nasal cavity, and palate before entering the maxilla to supply the teeth and nasal structures. In both species, the lingual artery arose directly from the external carotid artery. The submental artery formed a common trunk with the glandular branch. The lips were supplied by branches of the facial, infraorbital, and mental arteries, with a distribution that differed from patterns reported in ruminants and perissodactyls. The stapedial artery was not observed. Conclusions Overall, the arterial pattern was largely similar in the two species. These findings provide a basis for further anatomical, physiological, and veterinary research on macropodids and may be relevant to clinical procedures involving the head.