Chelonian Anatomy

CAUSES TO IMAGE TURTLES

• Traumatic injuries of the shell and the ingestion of fishhooks, gravel/stones are the most frequent causes of admission to rescue centers

• Pulmonary disease can frequently occur secondary to damage to the carapace– Dorsal position of the lungs

ACCESSION 171533

AXIAL SKELETON

• Composed of the – Carapace– Plastron bones– Vertebrae– Ribs– And derivatives of the ribs

CARAPACE

• Carapace is formed by:– Scutes: outermost layer of the shell• Multiple scutes overlap the bony plates that are fused

with the vertebrae or ribs forming a single carapace bone

– Bony plates: main structural component of the shell• Neural, pleural and peripheral bones

PLASTRON

• VENTRAL SURFACE OF THE SHELL

• LIMITATIONS OF RADIOGRAPHY IN TURTLES• SUPERIMPOSITIONING OF

CARAPACE AND PLASTRON

USEFULNESS OF CT

SKELETAL SYSTEM

CORACOID

SCAPULA

HUMERUS

ACROMION

SCAPULA

GASTROINTESTINAL

1: ventricle; 2: right atrium; 3 left atrium

4: pectoral musculature 5’ and 5’’ left and right hepatic lobes, respectively;

6: stomach; 7: gallbladder 8: esophagus 9: trachea 10: small intestine 11:large intestine 12: rectum

RESPIRATORY SYSTEM• LUNGS ARE NOT LOBED

• PULMONARY PARENCHYMA IS HIGHLY RETICULATED

1 central bronchus

2 pulmonary vasculature

3 pulmonary artery

4 pulmonary vein

1 scapula2 1st pair of ribs3 8th cervical vertebra,4 3rd dorsal vertebra5 pulmonary parenchyma.

RESPIRATORY PATHOLOGY

• Inflammatory exudates particularly those associated with infectious diseases tend to accumulate in the dependent portion of the

lung• Pneumonia: seen as loss of normal reticular

lung with alveolar pattern, typically seen in the ventral lung

1 kidneys2 intestinal loop3 pubic bones. 4 renal veins 5 branch of the external iliac vein6 aorta artery

RENAL SYSTEM

• Kidneys located retroperitoneally between the peritoneum and the shell

• Metanephric– Kidney tubules are drained by the ureters(metanephric

ducts) and empty into the dorsal cloaca– Lack a distinct cortx, medulla, and renal pelvis– Seen on CT as homogenous parenchyma contrasting

only with the perinephric fat between the kidneys and carapace

ARTERIAL SYSTEM• THREE CHAMBERED HEART

• 2 ATRIA • 1 VENTRICLE

REFERENCES1. A.L.S. Valente a, R. Cuenca a, M. Zamora b, M.L. Parga c, S. Lavin a, F. Alegre c, I. Marco. Computed tomography of the

vertebral column and coelomic structures in the normal loggerhead sea turtle (Caretta caretta). The Veterinary Journal 174 (2007) 362–370

2. Witherington, Dawn, Wyneken, Jeanette. Chelonian Anatomy. Exotic DVM Vol 4.6. January 2003

3. Valente A, CuencavR, Parga M, Lavin S, Franch J, and Marco I. Cervical and coelomic radiologic features of the loggerhead sea turtle, Caretta caretta Can J Vet Res. 2006 October; 70(4): 285–290.