Ultrasonographic anatomy of coelomic organs in clinically healthy Eastern hellbenders (Cryptobranchus alleganiensis alleganiensis)

Eastern hellbender (Cryptobranchus alleganiensis alleganiensis) population densities have declined in recent years, because of minimal recruitment rates, anthropogenic stress, and infectious diseases.1,2 This species is the subject of numerous conservation programs and is often exhibited at zoological facilities. Despite the frequency with which these animals are managed under human care, no standardized ultrasonographic evaluation of their coelom has been conducted. Ultrasounds were performed on 39 hellbenders (12 females, 27 males) in ventral recumbency with no chemical or physical restraint. The aorta, caudal vena cava, heart, lungs, liver, gallbladder, esophagus, stomach, colon, spleen, and kidneys were identified, described, and measured in all animals. Echocardiographic measurements included ventricle length, wall thickness, chamber diameter, and fractional shortening in 37/39 animals. Measurements of reproductive structures were obtained for testicles (25/27 males), epidydimal tubules (16/27 males), and follicles (10/12 females). Two animals were excluded from statistical analysis of measurements in this study because of pathology identified during sonograms. All measurements had significant positive correlations with body weight and rostrum-to-cloaca length. Females had larger body mass (p = 0.01) and body length (p = 0.004) than males. Small quantities of coelomic and pericardial effusion were present in all hellbenders. This study examined Eastern hellbender ultrasonographic anatomy to aid antemortem diagnosis of coelomic pathology.