New CT atlas offers coelomic reference for yellow-legged gulls
Bottom line
Yellow-legged gull clinicians now have a species-specific CT reference for the coelomic cavity, with a new atlas describing normal cross-sectional anatomy and CT appearance in Larus michahellis. In the study, posted as a 2026 preprint, researchers examined eight adult gull carcasses; six underwent 16-slice helical CT followed by frozen transverse sectioning, and two were dissected for anatomic correlation. The authors say the work fills a gap in avian imaging literature, where yellow-legged gull CT publications had been limited largely to a nasal cavity study and an isolated shoulder trauma case report. (preprints.org)
Why it matters: Yellow-legged gulls are described by the authors as common patients in Mediterranean and Atlantic wildlife rehabilitation settings, and the lack of species-specific coelomic CT references has made interpretation more dependent on extrapolation from parrots, ducks, puffins, or shearwaters. That matters because avian coelomic imaging is already challenging on plain radiographs, while prior avian imaging literature has characterized CT as the preferred modality when coelomic disease is suspected because it better defines organ relationships and soft tissue detail. For veterinarians working in wildlife, exotics, or referral imaging, a gull-specific atlas could improve confidence when assessing trauma, organ displacement, reproductive structures, or other coelomic abnormalities. (preprints.org)
What to watch: The next step is whether this preprint advances to peer-reviewed publication and whether follow-on studies add live-patient reference values, contrast-enhanced imaging, or pathologic case comparisons in gulls and related seabirds. (preprints.org)
Key facts
- Species
- Yellow-legged gull (*Larus michahellis*)
- Study type
- 2026 preprint anatomical CT atlas
- Study aim
- Normal cross-sectional anatomy and CT appearance of the coelomic cavity
- Sample size
- Eight adult gull carcasses
- Imaging method
- Six specimens had 16-slice helical CT, then frozen transverse sectioning
- Anatomic correlation
- Two additional specimens were dissected
- Literature gap
- Prior CT work in yellow-legged gulls was limited to a nasal cavity study and an isolated shoulder trauma case report
- Clinical context
- Commonly seen in Mediterranean and Atlantic wildlife rehabilitation settings
A new anatomical CT atlas aims to give wildlife and avian clinicians a clearer baseline for interpreting the coelomic cavity in the yellow-legged gull, Larus michahellis, a species commonly seen in rehabilitation centers across Mediterranean and Atlantic regions. According to the 2026 preprint, the study was designed to map normal cross-sectional anatomy and CT appearance in this gull species, addressing what the authors describe as a missing reference in the veterinary imaging literature. (preprints.org)
That gap is fairly specific, but clinically relevant. The authors note that yellow-legged gulls are among the more frequently encountered free-ranging seabirds in Mediterranean-Atlantic veterinary practice, yet published CT work in the species appears to have been limited to a nasal cavity study and an isolated shoulder trauma report. In parallel, other avian groups have gradually built out coelomic imaging references, including pet parrots, Pekin ducks, juvenile Atlantic puffins, and Cory’s shearwaters, underscoring how uneven the species coverage still is in avian diagnostic imaging. (preprints.org)
In this study, eight adult yellow-legged gull carcasses were included. Six specimens underwent CT on a 16-slice helical scanner and were then frozen and sectioned transversely, while two additional specimens were dissected for detailed anatomic comparison. The atlas pairs gross anatomy, cross-sections, and CT images to identify major coelomic structures and their spatial relationships, including hepatic lobes, gastrointestinal segments, spleen, kidneys, ureters, ovary, uterus, cloaca, and air sacs. The preprint says the resulting reference is intended to support CT interpretation in clinical, rehabilitation, and research settings. (preprints.org)
The broader imaging context helps explain why this matters. Prior avian CT literature has emphasized that plain radiography can be difficult to interpret in birds because of the compact arrangement of coelomic organs and limited intracoelomic fat, while CT offers more precise anatomic detail and better assessment of organ relationships. Comparable atlas-style studies in parrots, ducks, and shearwaters have been framed as practical tools for distinguishing normal anatomy from pathology, especially in species where clinicians may otherwise rely on cross-species assumptions. (pmc.ncbi.nlm.nih.gov)
I didn't find outside expert commentary specific to this new gull atlas, but the surrounding avian imaging literature points in the same direction: species-specific references are still limited, and that limitation can affect interpretation in uncommon or wildlife patients. The Association of Avian Veterinarians also continues to offer dedicated education on avian coelomic radiology, suggesting sustained clinical demand for better imaging frameworks in this area. That makes this atlas less of a niche anatomy exercise and more of a practical reference for clinicians who only occasionally image seabirds. (aav.org)
Why it matters: For veterinary professionals, especially those in wildlife rehabilitation, zoological medicine, exotics practice, and referral radiology, the value here is standardization. A species-specific atlas can help reduce overreliance on parrot or domestic waterfowl anatomy when evaluating gulls with trauma, suspected gastrointestinal disease, reproductive pathology, foreign material, or nonspecific coelomic changes. Because yellow-legged gulls are regularly admitted to rehabilitation centers, even a cadaver-based reference may improve report accuracy, case triage, teaching, and communication between frontline clinicians and imaging specialists. That last point is partly an inference, but it is consistent with the study’s stated goal of facilitating diagnostic image interpretation and with how similar avian atlases have been positioned in prior literature. (preprints.org)
There are also clear limitations. This is a preprint, not yet peer reviewed, and the sample was small, with eight adult carcasses rather than live clinical patients. That means the atlas is best viewed as a foundational normal-anatomy reference, not a complete diagnostic standard. It also doesn't yet answer questions about normal variation across age classes, sex, body condition, contrast enhancement, or the appearance of common disease processes in rescued gulls. (preprints.org)
What to watch: The immediate next step is formal peer-reviewed publication. After that, the most useful follow-up studies would likely be live-patient CT series, quantitative measurements and attenuation values, and case-based comparisons covering trauma, infectious disease, reproductive disorders, and other coelomic pathology in gulls and related seabirds. (preprints.org)