CT Atlas of the Coelomic Cavity in the Yellow-Legged Gull (Larus michahellis)

The Yellow-legged Gull (Larus michahellis) is one of the most frequently admitted seabirds to wildlife rehabilitation centers in the Mediterranean and Atlantic regions. Despite its clinical relevance, detailed computed tomographic references of the coelomic cavity are lacking. The aim of this study was to describe the normal cross-sectional anatomy and computed tomographic appearance of the coelomic cavity in this species and to develop an anatomical atlas to facilitate diagnostic image interpretation. Eight young adult female Yellow-legged Gull were examined post-mortem. Six specimens underwent computed tomography using a 16-slice helical scanner, followed by frozen transverse sectioning, while two specimens were dissected to provide detailed anatomical correlation. CT datasets were evaluated using bone, soft tissue, and pulmonary window settings, and three-dimensional volume-rendered reconstructions were generated. Anatomical dissections, cross-sectional slices, and CT images enabled identification and characterization of the principal structures of the respiratory, cardiovascular, digestive, urinary, and reproductive systems, as well as their spatial relationships within the coelomic cavity. The combined evaluation of gross anatomy and CT imaging allowed accurate recognition of major organs, air sacs, large vessels, and skeletal landmarks throughout the examined sections. The atlas provides a comprehensive reference for normal coelomic anatomy in Larus michahellis and establishes a baseline for the interpretation of CT examinations in clinical, rehabilitation, and research settings. These findings may improve diagnostic accuracy and support future investigations of coelomic disorders in this species.