The pampas deer belongs to the Cervidae family (Artiodactyla order). It used to be a common and abundant species that had a wide distribution. However, at the end of the 19th century, the populations were decimated. In general, the hearts of mammals share many similarities, but size, shape, position, vessel organization and branching can vary among species. The objective of the present study was to describe the macroscopic morphology, topography and irrigation of the heart of the pampas deer. The anatomical study was conducted with 20 animals that had died of natural causes. The animals were studied by simple dissection. All animals had colored latex injected into one of the common carotid arteries to facilitate the visualization. The position of the heart, with a 45° axis, the presence of a double sternopericardial ligament, and the bilateral cardiac circulation were some of the notable findings.

The pampas deer (Ozotoceros bezoarticus) is a medium-sized deer that weighs 20-40 kg. Historically, it was a widely distributed species that occupied a wide range of open habitats, including pastures, pampas, and Brazilian savanna. However, it is currently considered to be a species at risk of extinction. Anatomical descriptions of the arterial supply are very useful when working with exotic mammals. Knowledge of the locations, the distribution pattern, and the anatomical relationships of the arteries is required when performing any intervention. The objective of this research was to describe the normal arterial distribution pattern in the head and neck of this species. The divisions of the common carotid arteries, to which branches of the vertebral arteries are attached, irrigate the head and cranial parts of the neck. The arterial distribution pattern in the head and neck of the pampas deer was found to be similar to that described for other cervids and bovines but showed important differences from that for the ovine. The pampas deer had a bicarotid trunk, in contrast to other cervids. With regard to domestic animals, the lack of a fully developed internal carotid artery and the marked presence of a linguofacial trunk mean that it resembles the arterial distribution described for bovines.