Pathologic Findings in Weedy (Phyllopteryx taeniolatus) and Leafy (Phycodurus eques) Seadragons

Abstract

A retrospective study of the pathologic findings in weedy (Phyllopteryx taeniolatus) and leafy (Phycodurus eques) seadragons was performed on specimens submitted to 2 reference laboratories from 1994 to 2012 to determine the range and occurrence of diseases affecting aquarium-held populations. One hundred two and 94 total diagnoses were recorded in weedy and leafy seadragons, respectively. Two of the more common etiologic diagnoses in both species were mycobacteriosis and scuticociliatosis, whereas myxozoanosis was common in weedy seadragons. Metazoan parasite infections were less common etiologic diagnoses. There were no correlations between mycobacteriosis and ciliate protozoan infections in either species. Myxozoanosis was usually found in combination with other diseases and, except for 1 case, was restricted to weedy seadragons. Phaeohyphomycosis, nonmycobacterial bacterial infections, and trauma were also important but less frequent diagnoses. Intestinal coccidiosis was found in weedy but not leafy seadragons. Mineralization of the swim bladder was detected in 26 of 197 leafy seadragons and only 2 of 257 weedy seadragons. Although weedy and leafy seadragons share certain diseases of significance to exhibit populations, there are diseases unique to each species about which the veterinary pathologist, clinician, or diagnostician should be aware.

Pathologic features of mycobacteriosis in naturally infected Syngnathidae and novel transcriptome assembly in association with disease

“…Commonly displayed in aquaria, seahorses, seadragons and pipefish suffer significant losses, due primarily to M. chelonae (Berzins & Greenwell ; LePage ; Bonar et al . ). While M. chelonae was also the most commonly identified isolate in this study, other NTM infect syngnathids and cause similar lesions (Balcázar et al .…”

“…Mycobacteriosis is of special concern in captive syngnathids (seahorses, seadragons and pipefish) (Berzins & Greenwell ; Balcázar, Planas & Pintado ; LePage ; Bonar et al . ; LePage et al . ).…”

“…In addition, syngnathids appear to have an atypical pathologic presentation when compared to other teleosts (Bonar et al . ), but a comprehensive evaluation across the family has not been performed. In most teleosts, microscopic lesions are characterized by discrete granulomas containing the mycobacteria (Kent et al .…”

Gas gland adenoma in a lined seahorse, Hippocampus erectus, Perry 1810

“…Loss of habitat, changing climate and human harvesting threaten wild populations of many syngnathid species (Vincent, Foster, & Koldewey, ). In captivity, syngnathids are susceptible to infectious diseases including mycobacteriosis, scuticocilliatosis, phaeohyphomycosis, fusariosis and vibriosis (Bonar et al., ; LePage et al., ; Nyaoke et al., ; Salter et al., ). Aside from water quality‐related issues, particularly gas bubble trauma, non‐infectious diseases, such as neoplasia, are less commonly reported in syngnathids.…”

“…Aside from water quality‐related issues, particularly gas bubble trauma, non‐infectious diseases, such as neoplasia, are less commonly reported in syngnathids. Neoplasms described in the lined seahorse ( Hippocampus erectus ) include fibrosarcoma (Willens, Dunn, & Frasca, ) and angioma/lymphangioma (Boylan et al., ); the weedy seadragon ( Phyllopteryx taeniolatus ), cardiac rhabdomyosarcoma (LePage et al., ) and pancreatic islet cell neoplasia (Bonar et al., ); the leafy seadragon ( Phycodurus eques ), hepatocellular adenoma and islet cell neoplasia (Bonar et al., ); and the yellow seahorse ( Hippocampus kuda ), renal adenoma, renal adenocarcinoma, renal round cell tumour (presumptive lymphoma), exocrine pancreatic carcinoma and intestinal carcinoma (LePage et al., ).…”