DESCRIPTION OF TRANSCOELOMIC AND TRANSESOPHAGEAL ECHOCARDIOGRAPHY IN HEALTHY HUMBOLDT PENGUINS (SPHENISCUS HUMBOLDTI)

Although cardiac pathology has been documented in penguin species under managed care, routine or pathologic assessment of cardiac function in penguins is poorly described in the literature. This study assessed cardiac function through transcoelomic (TCE) and transesophageal (TEE) echocardiography in 11 apparently healthy Humboldt penguins (Spheniscus humboldti). TCE was performed in awake and sedated birds under manual restraint, as well as under general anesthesia (GA). The use of IM midazolam and butorphanol provided an inadequate level of sedation, so only images from awake and anesthetized exams were evaluated. Using TCE, acceptable monoplane images were obtained in 51.5% (17/33) and 75.8% (25/33) of exams during awake manual restraint and under GA, respectively. Under GA, all intended imaging planes were obtained via TEE and 100% (33/33) of examinations resulted in acceptable images. Left ventricular end diastolic volume (LVEDV) values were significantly higher in awake penguins than anesthetized penguins regardless of echo technique (p < 0.05). Left ventricular end systolic volume (LVESV) values were significantly higher using TCE than TEE regardless of consciousness state (p < 0.05), but the opposite was true for left ventricular ejection fraction (LVEF) (p < 0.05). Based on these results, TCE is an adequate imaging modality for basic cardiac assessment in awake and anesthetized penguins, whereas TEE is the preferred modality for more detailed cardiac assessments.