Ultrasonographic Morphology of the Abdominal Organs of the White-Eared Opossum (Didelphis albiventris)

Ultrasound is a fundamental diagnostic imaging tool in veterinary medicine that allows for the noninvasive, real-time evaluation of abdominal organs. However, reference ultrasound data for neotropical marsupials is scarce, which hinders diagnostic interpretation of ultrasound images of these species. The present study aimed to describe the morphological and biometric ultrasound characteristics of the abdominal organs of white-eared opossums (Didelphis albiventris) treated at a wildlife rehabilitation center in southern Brazil. Sixteen clinically stable opossums, with an average body mass of 1.4 kg, underwent abdominal ultrasonography using a multifrequency linear transducer (7–12 MHz). We analyzed parameters such as shape, contour, echogenicity, echotexture, and anatomical relationships between adjacent structures, in addition to taking biometric measurements of different abdominal organs. Most structures presented characteristics similar to those described in small domestic dogs and cats. However, species-specific particularities were observed, including decreased renal corticomedullary distinction, slightly coarser renal and prostatic echotexture, and a smaller abdominal aorta diameter. It is concluded that abdominal ultrasonography is an effective method for the anatomical evaluation of white-eared opossums.