Abstract

Leafy (Phycodurus eques) and weedy sea dragons (Phyllopteryx taeniolatus) are related to seahorses and pipefish, and are found in reefs and sandy underwater regions of Western Australia, South Australia, and further east along the coastline of Victoria, Australia. These fish are protected under Australian law, and have become popular recently for aquarium exhibits in the United States. With the exception of a few parasites and vibriosis,^1-6 little is known of the pathogens or other disease processes of sea dragons. The report summarizes the pathologic findings in 148 weedy sea dragons (WSD) and 97 leafy sea dragons (LSD) submitted to Northwest ZooPath from 1994 to early 2005, and the Connecticut Veterinary Medical Diagnostic laboratory from 1999–2005.

Table 1 summarizes the disease processes diagnosed in LSD and WSD. Thirty-four disease processes were identified in WSD and 28 disease processes were identified in LSD. Some fish had multiple disease processes. Diseases commonly seen in both species were ciliated protozoan infections, mycobacteriosis, and various forms of dermatitis. Emaciation and no pathologic changes were also common diagnoses in WSD. Some important infectious diseases that occurred in WSD but not in LSD were myxozoanosis, intestinal coccidiosis, and branchial epitheliocystis-like inclusions.

Table 1. A summary of diseases of leafy and weedy sea dragons submitted to Northwest ZooPath (1994–2005) and University of Connecticut (1999–2005)

^aIncludes cases of ulceration, erosion and underlying cellulites.
^bWeedy sea dragons had additional single case diagnoses of stomatitis, unidentified parasite granulomas, ammonia toxicosis, cataract, osmoregulatory disturbance, bacteria nephritis, mineralization, hepatic necrosis, diatoms, mycotic stomatitis, and probable viral branchitis.
^cLeafy sea dragons had additional single case diagnoses of renal tubular dilatation, osmoregulatory disturbance, hematopoietic depletion, goiter, flagellates, amoeba, nephrosclerosis, and biliary mucolith.

Acknowledgments

The authors thank the following institutions for contributing cases: Tennessee Aquarium, Monterey Bay Aquarium, National Aquarium (Baltimore), Aquarium of the Pacific (Long Beach), Aquarium of the Americas, Dallas World Aquarium, Waikiki Aquarium, Texas State Aquarium, Pittsburg Zoo and Aquarium, Underwater Adventures, the Toledo Zoo, Point Defiance Zoo & Aquarium, Indianapolis Zoo, The Seattle Aquarium, Henry Doorly Zoo, and the New Jersey State Aquarium (now Adventure Aquarium).

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