Two adult albino axolotls of unknown age designated for use in a teaching laboratory were noted to have firm white to yellow masses on their tails. These animals were otherwise healthy and were maintained in separate plastic aquaria containing approximately ten liters of water at a temperature of between fifteen and twenty degrees centigrade. They were fed a diet of earthworms, trout chow, mealworms, and freeze-dried bloodworms.
The axolotls were anesthetized with tricaine methanesulfonate (MS-222) at a concentration of 2.5 gm/L. Induction time was approximately ten minutes and the animals were placed in ventral recumbency on a moist surgical towel. The first salamander had a 0.5 centimeter spherical mass located on the dorsal aspect of the distal tail. This mass was excised with Metzenbaum scissors and placed in ten percent neutral buffered formalin. Care was taken to include unaffected tissue margins. The animal was recovered uneventfully in clean dechlorinated fresh water and returned to its aquarium. The second salamander had a 1.0 cm. elliptical plaque-like mass associated with the lateral aspect of its tail. Sterile forceps and a number 15 scalpel blade were used to remove this mass which was placed in ten percent neutral buffered formalin. Unaffected deep tissue margins were not obtained due to the invasive nature of the mass. Topical silver sulfadiazine cream was applied to the surgical site. The animal was recovered uneventfully in clean dechlorinated fresh water and returned to its aquarium.
Preliminary histopathological assessment indicates that these masses contain adipose tissue. A final diagnosis is pending.
Both patients continue to do well post-operatively and no recurrence has been noted.
We gratefully acknowledge the assistance of David Brazik and Maureen Trogdon.