Abstract

The hellbender (Cryptobranchus alleganiesis) is a large aquatic salamander native to the United States.^6,10 Hellbenders in the wild are threatened by stream impoundment, channelization, agricultural runoff (chemical and siltation), disturbances caused by recreational use, and thermal changes.¹¹ Batrachochytrium dendrobatidis (Bd) and ranavirus infection have been identified in wild populations^2,3,13 but the significance is unknown. Several gastrointestinal parasites have also been detected, but none appear to be clinically significant.^4,12 Leeches (Placobdella cryptobranchii) are often present⁸ and may be the vector of Trypanosoma cryptobranchi. Traumatic injuries to digits and appendages appear to be relatively common, and wild hellbenders are frequently found missing digits or limbs.⁵

In captivity, Bd may be significant in compromised hellbenders. Saprolegniasis is usually superficial and often associated with dermal lesions. Wounds may occur from intraspecific aggression, trauma, or exhibit materials. Persistent wounds may be a source of infection leading to sepsis. Hellbenders can be anesthetized with tricaine methanesulfonate (MS-222; 0.025%, or 250 mg/L). For surgical procedures, absorbable suture may dehisce; therefore, it is recommended to use nylon suture material in both internal and external layers. Radiography and ultrasonography are useful imaging modalities. Phlebotomy is performed from the caudal vein located along the ventral aspect of the tail. Injectable antibiotics are preferred to oral or topical (soaks) administration in hellbenders.⁷ Antifungal therapy may be necessary for management of Bd infections. Itraconazole soaks,⁹ hyperthermia,¹⁴ and topical chloramphenicol¹ may be effective.

Acknowledgments

Thanks to St. Louis Zoo Herpetology Department (J. Ettling, M. Wanner, C. Schuette) and Missouri Department of Conservation (J. Briggler) for letting me be on the team.

Literature Cited

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