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Abstract. Our study was undertaken to assess the application of semiautomated methods available at the reference laboratory level for the evaluation of plasma protein and cholesterol via electrophoresis in samples from cownose rays (Rhinoptera bonasus). Three groups of animals were assessed: clinically normal, clinically abnormal, and parasitized with leeches. As reported previously, the albumin band was negligible; the protein electrophoretograms were dominated by a large beta-globulin fraction. While the group of samples from the leech-parasitized rays did not show any large differences, the abnormal group exhibited significantly elevated total solids and cholesterol levels. The latter was related to a significant increase in very low density lipoprotein levels. The results demonstrate the potential application of these laboratory methods in quantitation of plasma proteins and cholesterol fractions in subclass Elasmobranchii.

Understanding the fundamental reproductive biology of a species is the first step toward identifying parameters that are critical for reproduction and for the development of assisted reproductive techniques. Ejaculates were collected from aquarium (n = 24) and in situ (n = 34) sand tiger sharks Carcharias taurus. Volume, pH, osmolarity, sperm concentration, motility, status, morphology, and plasma membrane integrity were assessed for each ejaculate. Semen with the highest proportion of motile sperm was collected between April and June for both in situ and aquarium sand tiger sharks indicating a seasonal reproductive cycle. Overall, 17 of 30 semen samples collected from aquarium sharks from April through June contained motile sperm compared to 29 of 29 of in situ sharks, demonstrating semen quality differences between aquarium and in situ sharks. Sperm motility, status, morphology, and plasma membrane integrity were significantly higher (P < 0.05) for in situ compared to aquarium sand tiger sharks. Testosterone was measured by an enzyme immunoassay validated for the species. Testosterone concentration was seasonal for both aquarium and in situ sharks with highest concentrations measured in spring and lowest in summer. In situ sharks had higher (P < 0.05) testosterone concentration in spring than aquarium sharks. This study demonstrated annual reproduction with spring seasonality for male sand tiger sharks through marked seasonal differences in testosterone and semen production. Lower testosterone and poorer semen quality was observed in aquarium sharks likely contributing to the species’ limited reproductive success in aquariums.

Preventative health care of elasmobranchs is an important but understudied field of aquatic veterinary medicine. Evaluation of inflammation through the acute phase response is a valuable tool in health assessments. To better assess the health of bonnethead sharks ( Sphyrna tiburo ) under managed care, normal reference intervals of protein electrophoresis (EPH) and the acute phase proteins, C-reactive protein (CRP) and haptoglobin (HP), were established. Blood was collected from wild caught, captive raised bonnethead sharks housed at public aquaria. Lithium heparinized plasma was either submitted fresh or stored at -80°C prior to submission. Electrophoresis identified protein fractions with migration characteristics similar to other animals with albumin, α-1 globulin, α-2 globulin, β globulin, and γ globulin. These fractions were classified as fractions 1-5 as fractional contents are unknown in this species. Commercial reagents for CRP and HP were validated for use in bonnethead sharks. Reference intervals were established using the robust method recommended by the American Society for Veterinary Clinical Pathology for the calculation of 90% reference intervals. Once established, the diagnostic and clinical applicability of these reference intervals was used to assess blood from individuals with known infectious diseases that resulted in systemic inflammation and eventual death. Unhealthy bonnethead sharks had significantly decreased fraction 2, fraction 3, and fraction 3:4 ratio and significantly increased fraction 5, CRP, and HP. These findings advance our understanding of elasmobranch acute phase inflammatory response and health and aid clinicians in the diagnosis of inflammatory disease in bonnethead sharks.

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

Descriptive information regarding the peripheral blood of normal whale sharks Rhincodon typus Smith 1828 is presented based on samples collected from 2 healthy female specimens held in an aquarium collection. Erythrocyte morphology was similar to other orectolobiforms and major leukocyte types were similar to other non-carcharhinid sharks. The numerically dominant population was the lymphocyte (46%), followed by the fine eosinophilic granulocyte or heterophil (39.5%). The remaining 15% of white blood cells were divided among coarse eosinophilic granulocytes or eosinophils, simple neutrophils, monocytes similar to those of most elasmobranchs and a rare basophilic stippled granulocyte or basophil. Thrombocytes were similar to those of other shark species; no granulated thrombocytes were observed in this species. Blood gas data and serum chemistry values are also presented. For comparison, 22 blood samples collected from 2 moribund male specimens showed that the heterophil/lymphocyte ratio may be a potentially useful biomarker of whale shark health. A pattern of marked heterophilia in these animals became more pronounced as their clinical condition deteriorated. These data represent the first exploration of the internal biology of the world's largest fish.

Acute phase proteins (APPs) have been studied in many companion and large animals and have been reported to have a differential sensitivity to traditional markers of inflammation. Studies have been performed indicating the conservation of these proteins as well as the application and cross-reactivity of automated assays among different species, but few reports have detailed APPs in marine mammal species. In the present study, automated assays were utilized to generate reference intervals for C-reactive protein, haptoglobin, and serum amyloid A using 44 serum samples from healthy Atlantic bottlenose dolphins (Tursiops truncatus). A total of 25 samples were obtained from dolphins under human care and 19 samples were obtained from free-ranging dolphins. Mild yet statistically significant differences were observed in levels of haptoglobin and serum amyloid A between these groups. The reference intervals from the combined groups were as follows: C-reactive protein 3.1-19.7 mg/l, haptoglobin 0-0.37 mg/ml, and serum amyloid A 17.5-42.9 mg/l. These baseline data should provide an important foundation for future studies of the application of APP quantitation in monitoring the health and stressors of dolphins under human care and with live capture of free-ranging dolphins.

In this report, two cases of systemic mycosis in captive sharks are characterized. These cases were progressive and ultimately culminated in terminal disease. Paecilomyces lilacinus, an uncommon pathogen in human and veterinary medicine, was associated with areas of necrosis in the liver, heart, and gill in a great hammerhead shark (Sphyrna mokarran). Fungal growth was observed from samples of kidney, spleen, spinal fluid, and coelomic cavity swabs. Dual fungal infection by Exophiala pisciphila and Mucor circinelloides was diagnosed in a juvenile zebra shark (Stegostoma fasciatum). Both fungi were present in the liver, with more severe tissue destruction associated with E. pisciphila. E. pisciphila also produced significant necrosis in the spleen and gill, while M. circinelloides was associated with only minimal tissue changes in the heart. Fungal cultures from liver, kidney, and spleen were positive for both E. pisciphila and M. circinelloides. Identification of P. lilacinus and M. circinelloides was based on colonial and hyphal morphology. E. pisciphila was identified by sequence analysis of the 28S rRNA D1/D2 region and the internal transcribed spacer (ITS) region between the 18S and 28S rRNA subunit. These cases, and a lack of information in the literature, highlight the need for further research and diagnostic sampling to further characterize the host-pathogen interaction between elasmobranchs and fungi.