Abstract
A 10-year-old male rough-toothed dolphin (Steno bredanensis) housed at Gulf World Marine Park presented on May 15, 2012 with yellow thickened blowhole discharge. The following day the dolphin had the same discolored sputum from blowhole, anorexia, dyspnea, gastrointestinal gas, diarrhea, and lethargy. Chuff sample and blood were taken. CBC results showed an elevated WBC of 9.5 x 103/µL and neutrophilia of 6,715/µL and an increased eosinophil count for this animal of 1,045/ µL. The erythrocyte sedimentation rate was 6 mm/h (dolphin's normal rate was 1 mm/h). The dolphin was immediately placed on antibiotics and posaconazole, awaiting a rule-out diagnosis of mucormycosis, which is endemic to the region.
Results from a local Florida lab diagnosed Mucoraceae as the isolate from the yellow sputum collected. Samples were sent to the University of Texas at San Antonio (UT-SA) for confirmation. On June 21, the samples sent to UT-SA failed to grow any species from the phylum Mucoromytina, but instead diagnosed the pathogen from the class Basidiomycetes. Two more samples were sent to UT-SA on June 20, including a small portion of a dark spongy mass that was expelled from the blowhole. Using the ITS region (internal transcribed spacer), the most widely sequenced DNA region in the molecular ecology of fungi and D1/D2 region, a large subunit of an RNA gene, the UT-SA lab was able to confirm a Basidiomycetes isolate most closely related to a Phanerochate species, a genus in the division of fungi called Basidiomycota.
Basidiomycota is a large phylum (division) containing jelly, shelf fungi, mushrooms, puffballs, rusts and smuts. Most of these organisms have a club-shaped spore-bearing organ (basidium) and fruiting bodies called basidiocarps and most species are either nonpathogenic to humans and animals or are used in bioremediation of timber as they have specialized lignin components that break down wood.
With correct identification of the pathogen, posaconazole was discontinued and the dolphin was placed on itraconazole. Rasping breaths continued, but overall attitude began to improve, though sequential samples from the blowhole were still described as discolored, copious, and thickened. Over the next several weeks the animal continued to improve and eventually the infection resolved.
Upper respiratory infections are not rare in collection cetaceans, including ones of fungal etiology. The speciation results of a basidiomycete isolate in a dolphin, namely a Steno species, have not been documented in the literature.
Acknowledgments
We would like to thank all of the animal care team and trainers for all of their hard work during the diagnosis and treatment of this animal.
* Presenting author