Cory's Shearwater (Calonectris borealis): Exploring Normal Head Anatomy through Cross-Sectional Anatomy, Computed Tomography and Magnetic Resonance Imaging

Cory's shearwater, or Calonectris borealis, stands out as a symbolic figure in the world of seabirds, playing a crucial role in marine ecosystems globally. Belonging to the Procellariidae family, it is singularized by its imposing wingspan and intricate migration patterns connecting it to various regions from the North Atlantic to the Pacific. Its role in the marine food chain, specialized diet and adaptation for nesting in the Canary Archipelago underscore its ecological importance. However, Cory's shearwater also faces important threats, such as the invasion of foreign species, highlighting the need for its conservation. Among the conservation issues, studies on its biology, the main threats it faces and its normal anatomy are essential to preserve marine biodiversity. Additionally, a variety of imaging techniques, such as computed tomography and magnetic resonance, facilitates the understanding of the bird's neuroanatomy and opens future research possibilities in comparative neuroscience. Moreover, this approach proves particularly relevant given the increasing attention these seabirds receive in environments such as zoos, rehabilitation centers and their natural habitat, where veterinarians play a crucial role in their care and well-being.

Cross Sectional Anatomy and Magnetic Resonance Imaging of the Juvenile Atlantic Puffin Head (Aves, Alcidae, Fratercula arctica)

The Atlantic puffin is a medium-sized seabird with black and white plumage and orange feet. It is distributed mainly along the northern Atlantic Ocean, and due, among other reasons, to human activities, it is in a threatened situation and classified as a vulnerable species according to the International Union of Conservation of Nature (IUCN). In this study, we used a total of 20 carcasses of juvenile Atlantic puffins to perform MRI, as well as anatomical cross-sections. Thus, an adequate description of the head was made, providing valuable information that could be helpful as a diagnostic tool for veterinary clinicians, who increasingly treat these birds in zoos, rehabilitation centers, and even in the wild.

Clinical, imaging, and pathologic features in cases of neurologic disease in 3 psittacine birds

We used magnetic resonance imaging (MRI) to evaluate the CNS, and confirmed CNS lesions histologically, in 3 psittacine birds with neurologic signs. One bird was recumbent as a result of non-ambulatory paraparesis, and 2 birds were ataxic with impaired proprioception. In all 3 cases, imaging was performed, and infectious diseases were excluded in cases 1 and 2. In case 1, a large mass arose from the left lung; in case 2, a multinodular coelomic mass encompassed the left caudal pulmonary area to the left cranial renal pole; and in case 3, a diffuse hyperintensity affected the lumbar spinal cord. In the first 2 cases, masses invaded the vertebral canal, causing spinal cord compression. All 3 birds were euthanized given the poor prognosis, and postmortem examinations were performed. The final diagnoses were pulmonary adenocarcinoma in cases 1 and 2, and granulomatous and lymphocytic leptomeningitis caused by Mycobacterium genavense in case 3. MRI enabled visualization of the lesions in the affected area of the CNS, and MRI findings were confirmed by histopathology.

3.0 Tesla magnetic resonance imaging anatomy of the central nervous system, eye, and inner ear in birds of prey

Despite the increasing interest in the clinical neurology of birds, little is known about the magnetic resonance imaging (MRI) appearance of the avian central nervous system, eye, and inner ear. The objective of this cadaveric study was to document the MRI anatomic features of the aforementioned structures using a high-resolution 3.0 Tesla MRI system. The final study group consisted of 13 cadavers of the diurnal birds of prey belonging to six species. Images were acquired in sagittal, dorsal, and transverse planes using T1-weighted and T2-weighted turbo spin echo sequences. A necropsy with macroscopic analysis of the brain and spinal cord was performed on all cadavers. Microscopic examination of the brain was performed on one cadaver of each species; the spinal cord was examined in three subjects. Anatomic structures were identified on the magnetic resonance images based on histologic slices and available literature. Very good resolution of anatomic detail was obtained. The olfactory bulbs; cerebral hemispheres; diencephalon; optic lobe; cerebellum; pons; ventricular system; optic, trigeminal, and facial nerves; pineal and pituitary glands; as well as the semicircular canals of the inner ear were identified. Exquisite detail was achieved on the ocular structures. In the spinal cord, the gray and white matter differentiation and the glycogen body were identified. This study establishes normal MRI anatomy of the central nervous system, eye, and inner ear of the birds of prey; and may be used as a reference in the assessment of neurologic disorders or visual impairment in this group of birds.

Infiltrative Spinal Lipoma in a Canada Goose (Branta canadensis)

An adult Canada goose ( Branta canadensis ) was presented unable to walk. On physical examination, conscious proprioception was absent in both legs, and motor function was decreased. The bird did not improve with supportive care and was euthanatized and submitted for postmortem examination. Sagittal sectioning of the spine revealed an intradural growth causing segmental deformity of the lumbosacral spinal cord. The growth was diagnosed as an infiltrative spinal lipoma. Infiltrative lipomas are locally invasive, benign tumors that can be found in any host tissue. They have been documented in small and exotic companion animals, including birds; however, this is the first report of an infiltrative lipoma in the spinal canal of a bird or free-living wild animal.