Objective—To describe the gross cross-sectional
anatomy of green turtles (Chelonia mydas) and evaluate
magnetic resonance imaging (MRI) for detection
of internal tumors in green turtles with cutaneous
Animals—3 dead green turtles, 1 healthy green turtle,
and 8 green turtles with cutaneous fibropapillomatosis.
Procedures—Gross cross-sectional anatomy of a
dead turtle was described. Each live turtle underwent
a complete physical examination, and dorsoventral
whole-body survey radiographic views were obtained.
Magnetic resonance imaging was performed in dorsal
and transverse planes. Radiographs and magnetic
resonance images were examined for evidence of
internal nodules. Results were compared with
necropsy findings in 5 of 8 turtles.
Results—Nodules in the lungs of 2 turtles were
detected via radiography, whereas pulmonary nodules
were detected in 5 turtles via MRI. No other visceral
nodules were detected via radiography; however,
masses in the stomach and adjacent to the bladder
and kidneys were detected in 1 turtle via MRI. Other
extrapulmonary abnormalities observed at necropsy
were not detected on MR images.
Conclusions and Clinical Relevance—MRI may be
valuable for detection of internal tumors in green turtles
with cutaneous fibropapillomatosis. Nodules
were more apparent in the lungs than in other organs.
Results of MRI may serve as prognostic indicators for
sea turtles undergoing assessment, treatment, and
rehabilitation. Clinical application may be limited by
cost and availability of MRI technology. (J Am Vet Med Assoc 2004;225:1428–1435)
Objective—To determine thiamine-dependent enzyme activities in various tissue samples of Pacific harbor seals (Phoca vitulina) and thiaminase activities in dietary fish.
Animals—11 Pacific harbor seals with thiamine deficiency and 5 control seals.
Procedures—Seals underwent evaluation to rule out various diseases and exposure to toxins. For seals that died, measurement of thiamine-dependent enzymes in liver and brain samples and determination of mitochondrial DNA (mtDNA) copy number in liver, brain, and muscle samples were performed. Thiaminase activity in dietary fish was determined.
Results—8 seals with thiamine deficiency died. Affected seals typically had acute neurologic signs with few nonspecific findings detected by means of clinicopathologic tests and histologic examination of tissue samples. Thiamine-dependent enzyme activities in liver samples of affected seals were significantly lower than those in control liver samples. The primary activation ratios and latencies for enzymes indicated that brain tissue was more affected by thiamine deficiency than liver tissue. Activities of pyruvate dehydrogenase were more affected by thiamine deficiency than those of transketolase and ketoglutarate dehydrogenase. For control seals, the mtDNA copy number in muscle samples was significantly lower than that for affected seals; conversely, the copy number in control liver samples was significantly greater than that of affected seals. Thiaminase activity was substantially higher in smelt than it was in other types of dietary fish.
Conclusions and Clinical Relevance—Results of analyses in this study confirmed a diagnosis of thiamine deficiency for affected seals resulting from high thiaminase activity in dietary fish, inadequate vitamin administration, and increased thiamine demand caused by pregnancy and lactation.