Abstract
We report on an outbreak of Paecilomyces in a group of Loggerhead turtle (Caretta caretta) hatchlings that were originally collected for a research project investigating hatchling fitness, and that were subsequently treated at uShaka Sea World.
Fungal infections in reptiles are generally described as opportunistic, and due to physiological stress that results in immunosuppression. Reports indicate that Chelonia are particularly prone to mycotic pneumonia.1 During the initial research project all routine husbandry and animal welfare measures were observed. However, we suspect that, despite being kept in water which was heated to within the optimum temperature range required for the hatchlings, they were nevertheless exposed to cold ambient room air. This would have resulted in an extreme temperature disparity and, as young turtle hatchlings drift on the top of the water, the extreme temperature gradient between the ambient air and warmed water experienced could have caused extended physiological stress. Keeping reptiles at temperature below the optimum temperature range is a common cause of immunosuppression. However, hypothermia alone may impair function of the mucociliary apparatus and could also predispose these turtles to fungal pneumonia.2
Morbidity, as well as mortality was high (84%). The animals presented severely underweight, dehydrated, and lethargic. Negative buoyancy was also noted. Treatment, which consisted of a triple antifungal regimen, was regarded as unsuccessful. Resistance to antifungal treatment was high. In spite of keeping the animals in separate containers and adhering to rigorous disinfection protocols, it was possible for the initial infection to spread quickly to others in the group. It is assumed that this is due to the fact that large numbers of spores can easily be disseminated through the air. The infection resulted in a predominantly granulomatous pneumonia. Histopathology revealed a mycotic pneumonia with associated oxalate nephrosis.
To date only 5 animals have been released, with 3 currently receiving treatment. Even though Paecilomyces has previously been reported as causing systemic infection in sea turtles,3,4 this is the first report of an outbreak involving multiple animals in a group of hand-reared Loggerhead turtle hatchlings.
Acknowledgements
The authors would like to acknowledge the tremendous work performed by the staff that treated the affected animals - the uShaka Sea World quarantine staff and Animal Health Department, as well as those of the Bayworld Aquarium, Port Elizabeth.
* Presenting author
Literature Cited
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2. Innis C, Nyaoke AC, Williams CR, et al. 2009. Pathologic and parasitologic findings of cold-stunned Kemp’s ridley sea turtles (Lepidochelys kempii) stranded on Cape Cod, Massachusetts, 2001–2006. J Wildl Dis. 45:594–610.
3. Jacobson ER, Gaskin JM, Shields RP, et al. 1997. Mycotic pneumonia in mariculture-reared green sea turtles. J Am Vet Med Assoc. 175:929–933.
4. Hernandez-Divers SJ, Norton T, Hernandez-Divers SM, et al. 2002. Endoscopic diagnosis of pulmonary granulomas due to Paecilomyces in a juvenile sea turtle, Caretta caretta. In: Proceedings of the Association of Reptilian and Amphibian Veterinarians. Reno, Nevada; 3–4.