The carotid artery (A. carotis, Halsschlagader) is an important blood vessel that transports oxygen-rich blood from the heart to the head and brain. In dogs and cats, as in humans, it divides into two main branches: the internal and external carotid arteries. The internal carotid artery supplies blood to the brain, while the external carotid artery carries blood to the parts of the head outside the brain.