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Gastrointestinal tract contrast medium studies are a valuable diagnostic modality to evaluate gastrointestinal anatomy, motility, and pathology. Four positive contrast medium studies were performed twice on a harbor seal (Phoca vitulina) and once each on two California sea lions (Zalophus californianus) to evaluate for gastrointestinal abnormalities by using barium-impregnated gelatin. Because marine mammals in human care routinely receive plain gelatin as a component of their diet and as secondary reinforcement, feeding a barium gelatin mitigates the need for tube feeding or restraint. Operant conditioning was used to position the pinnipeds for voluntary radiographs. The barium gelatin permitted adequate evaluation of gastric emptying and intestinal transit times and good evaluation of the structure of the intestinal tract. Full evaluation of gastric anatomy was limited due to the gelatin blocks not conforming to the stomach in their solid form and the barium quickly exiting the stomach as barium gelatin blocks disintegrated and because orthogonal views could not always be acquired. Even with these limitations, barium gelatin resulted in diagnostically valuable contrast imaging in a stress-free patient setting with reduced risk of aspiration and eliminated the effects that anesthesia can have on gastric motility as well as other anesthesia-associated risks. [ABSTRACT FROM AUTHOR]

A juvenile, male tiger shark (Galeocerdo cuvier) developed illness after capture in Florida waters and was euthanized. Gross lesions included mild skin abrasions, hepatic atrophy, and coelomic fluid. Histologically, gills contained multifocal lamellar epithelial cell necrosis and thromboses. Scattered gill and esophageal epithelial cells had large, basophilic, intracytoplasmic, and intranuclear inclusions. Ultrastructurally, lamellar epithelial cells contained arrays of intracytoplasmic viral particles and scattered intranuclear nucleocapsids. Capsulated virions were 148 ± 11 nm with an 84 ± 8 nm icosahedral nucleocapsid and an electron-dense core. Next-generation sequencing, quantitative polymerase chain reaction, and in situ hybridization performed on formalin-fixed tissue confirmed a herpes-like viral infection. The viral polymerase shared 24% to 31% protein homology with other alloherpesviruses of fish, indicating a divergent virus. This report documents the pathologic findings associated with a molecularly confirmed novel herpes-like virus in an elasmobranch. [ABSTRACT FROM AUTHOR]

General anesthesia is often required in elasmobranch species for medical procedures. A variety of anesthetic drugs have been administered to elasmobranchs with wide variability in efficacy and safety. A retrospective review of 47 anesthetic procedures using IV propofol in eight different elasmobranch species at the Georgia Aquarium from 2010 to 2022 was performed. Cases involving seven sand tiger sharks ( Carcharias taurus ), four largetooth sawfish ( Pristis perotteti ), one longcomb sawfish ( Pristis zijsron ), four blacktip reef sharks ( Carcharhinus melanopterus ), three silvertip sharks ( Carcharhinus albimarginatus), one sandbar shark ( Carcharhinus plumbeus ), five cownose rays ( Rhinoptera bonasus ), and one blotched fantail stingray ( Taeniura meyeni ) were evaluated. Induction dose of IV propofol (median: 2.5; 25-75%: 2.3-3.0; range: 1.7-4.0 mg/kg), time to desired effect (median: 4.0; 25-75%: 2.0-5.0; range: 0.5-15.0 min) and anesthetic duration (median: 76.0; 25-75%: 61.5-119.0; range: 27-216 min) were reported in all species. In six procedures (12.7%), maintenance of desired anesthetic plane required a supplemental dose of propofol IV (1 mg/kg) or addition of tricaine methanesulfonate (70 mg/L) as an immersion bath. The most common side effects were apnea and prolonged recovery. The IV propofol was efficacious and provided a procedural plane of anesthesia for a clinically relevant period of time in the majority of elasmobranch species, but observation for and management of complications is warranted.

A 7.5 kg common carp Cyprinus carpio presented with prominent localized swelling in the caudal right coelomic area, identified by ultrasound as a fluid filled mass. Fine needle aspirate (FNA) and culture results suggested a sterile seroma. Centesis removed 290 ml of serosanguinous fluid that returned within days. Recheck ultrasonography revealed a solid component within the cavity. Radiography demonstrated irregular lysis and misalignment of vertebrae adjacent to the mass, most suggestive of bacterial osteitis or neoplasia. Treatment with antibiotics followed for 2 mo but failed to resolve the lesion. Repeated radiography and ultrasonography showed progressive enlargement of the mass, with vertebral lysis and invasion characteristic of neoplasia. Ultrasound-guided FNA of the solid component of the mass was non-diagnostic. Euthanasia was elected due to the poor clinical response and primary differential of neoplasia. Post-mortem MRI and CT confirmed a retroperitoneal soft tissue mass, partially surrounded by a fluid-filled cavity, causing vertebral lysis and infiltration of the spinal canal. Expansion of the mass caused severe muscle loss and an associated elevation in creatine kinase (>120000 U l-1). Necropsy results corroborated the MRI and CT findings, revealing a retroperitoneal, multilobular, red and tan mass causing dorsal displacement of the vertebral column, with vertebral lysis, pathologic fracture and invasion of the spinal canal. Histopathologic examination revealed a locally aggressive neoplasm exhibiting multiple patterns of growth, including endothelial lined vascular channels and solid areas formed by more pleomorphic polygonal and spindle cells, consistent with hemangiosarcoma.

During a 4 mo epizootic, 100% of 152 lined seahorses Hippocampus erectus in 3 separate groups died while in quarantine following shipment to a public aquarium. Twelve animals with skin depigmentation and ulceration were received by the Aquatic Pathology Service, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA, for diagnostic evaluation. Microscopically, lesions in 11 seahorses included multifocal epithelial necrosis and ulceration associated with 2 to 7 µm diameter, branching, septate fungal hyphae, typically accompanied by deeper infiltration into underlying skeletal muscle. Angioinvasion, with vascular thrombosis and tissue infarction, was a prominent feature in multiple animals. Fungal invasion of one or more internal organs was observed in 4 animals. Hyphae appeared to course freely through tissues and elicited little or no inflammatory response. Fusariosis has been reported sporadically in fish and other aquatic organisms, but identification has often been limited to the genus level based solely on morphologic features. Morphologic characteristics of the fungus isolated from this case were consistent with the Fusarium solani species complex (FSSC), which includes over 50 members that can only be identified definitively using DNA sequence data. A 3-locus typing scheme identified the isolate as a distinct species/haplotype, designated FSSC 12-a, belonging to a specific lineage that appears adapted to aquatic environments and disease in marine animals. Empirical treatment with itraconazole failed to stop mortalities, and subsequent in vitro antifungal susceptibility data explained a lack of clinical efficacy for this agent. Effective treatment in human medicine has similarly been limited by poor susceptibility to several classes of antifungal compounds.