PHAEOHYPHOMYCOSIS ASSOCIATED WITH OSSIFICATION OF THE SKULL AND CERVICAL VERTEBRAE IN A SWELL SHARK (CEPHALOSCYLLIUM VENTRIOSUM)

Abstract

A female, captive bred, juvenile swell shark ( Cephaloscyllium ventriosum ) was observed swimming in tight circles and rolling. Radiographs and computed tomography of this individual revealed extensive cartilage mineralization of the skull and cranial cervical vertebrae compared with diagnostic images of clinically healthy conspecifics. Gross necropsy and histopathologic examination revealed ossification and fibrosis of the cartilaginous matrix of the skull and cervical vertebrae with deep invasion by a pigmented hyphal fungus. There was no growth on fungal culture, but fungal polymerase chain reaction identified a DNA sequence compatible with Exophiala sp. (99%). Radiographs and computed tomography were helpful to determine a prognosis and course of action for this individual. This case emphasizes the need to include fungal infections as a differential diagnosis when evaluating elasmobranchs with abnormal swimming behaviors and mineralization of the skeletal structures.

Retrospective study of phaeohyphomycosis in aquarium‐housed fish, with first descriptions of Exophiala lecanii‐corni and Neodevriesia cladophorae in fish

“…in a swell shark, smooth dogfish, thorny back ray and the previously mentioned zebra shark (Erlacher-Reid et al, 2016;Gaskins & Cheung, 1986;Marancik et al, 2011;Yanong, 2003). Tissues affected by exophialosis in other elasmobranchs vary but additionally include the skull, cervical vertebrae, skin and brain (Erlacher-Reid et al, 2016;Gaskins & Cheung, 1986). fungi was made (Garner, 2013).…”

“…More recently, Veronaea botryosa emerged as a cause of systemic disease in hatchery‐reared Siberian sturgeon ( Acipenser baerii ) and white sturgeon ( Acipenser transmontanus ) resulting in significant economic losses annually (Coleman et al., 2018; Groff et al., 2020; Steckler et al., 2014). Additionally, individual and case series descriptions of melanized fungi causing disease in aquarium fish are reported periodically including in leafy seadragons ( Phycodurus eques ), weedy seadragons ( Phyllopteryx taeniolatus ), a Queensland grouper ( Epinephelus lanceolatus ), a zebra shark ( Stegostoma fasciatum ), a swell shark ( Cephaloscyllium ventriosum ), a smooth dogfish ( Mustelus canis ), splitnose rockfish ( Sebastes diploproa ) and a tomato clownfish ( Amphiprion frenatus ) (Bonar et al., 2013; Camus et al., 2015; Erlacher‐Reid et al., 2016; Gaskins & Cheung, 1986; Marancik et al., 2011; Nyaoke et al., 2009; Peel et al., 2021; Silphaduang et al., 2000).…”

Eumycetoma and disseminated phaeohyphomycosis in a Sumatran tiger

“…17 The condition has been documented in a wide range of species, including ectotherms, birds, ruminants, horses, dogs, and cats. 4,5,7,11,15,17,19,22,24 Disease may be associated with immunocompromised status. Some dematiaceous fungi are also capable of forming a mycetoma, an infection of skin and subcutaneous tissue by fungi (eumycetoma) or filamentous bacteria (actinomycetoma) that is uniquely accompanied by swelling, draining tracts, and grains, which in eumycetomas contain abundant fungal hyphae.…”

The Establishment of an Optimal Protocol for Contrast‐Enhanced Micro‐Computed Tomography in the Cloudy Catshark Scyliorhinus torazame

“…However, advanced diagnostic imaging with computed tomography (CT) on living elasmobranchs has been extremely limited, with one report using non‐contrast conventional CT in a Swell Shark Cephaloscyllium ventriosum with phaeohyphomycosis (Erlacher‐Reid et al. 2016). Additionally, there are reports of postmortem CT scans related to veterinary clinics, anatomy, embryology, and evolutionary biology (Preziosi et al.…”