The Ancient Evolutionary History of Polyomaviruses.

Polyomaviruses are a family of DNA tumor viruses that are known to infect mammals and birds. To investigate the deeper evolutionary history of the family, we used a combination of viral metagenomics, bioinformatics, and structural modeling approaches to identify and characterize polyomavirus sequences associated with fish and arthropods. Analyses drawing upon the divergent new sequences indicate that polyomaviruses have been gradually co-evolving with their animal hosts for at least half a billion years. Phylogenetic analyses of individual polyomavirus genes suggest that some modern polyomavirus species arose after ancient recombination events involving distantly related polyomavirus lineages. The improved evolutionary model provides a useful platform for developing a more accurate taxonomic classification system for the viral family Polyomaviridae.

Testosterone and progesterone concentrations in blow samples are biologically relevant in belugas (Delphinapterus leucas).

Steroid hormone analysis in blow (respiratory vapor) may provide a minimally invasive way to assess the reproductive status of wild cetaceans. Biological validation of the method is needed to allow for the interpretation of hormone measurements in blow samples. Utilizing samples collected from trained belugas (Delphinapterus leucas, n=20), enzyme immunoassays for testosterone and progesterone were validated for use with beluga blow samples. Testosterone concentrations in 40 matched blood and blow samples collected from 4 male belugas demonstrated a positive correlation (R2=0.52, p<0.0001). Progesterone concentrations in 64 matching blood and blow samples from 11 females were also positively correlated (R2=0.60, p<0.0001). Testosterone concentrations (mean±SD) in blow samples collected from adult males (119.3±14.2pg/ml) were higher (p<0.01) than that of a juvenile male (<8years) (59.4±6.5pg/ml) or female belugas (54.1±25.7pg/ml). Among adult males, testosterone concentrations in blow demonstrated a seasonal pattern of secretion, with peak secretion occurring during the breeding season (February-April, 136.95±33.8pg/ml). Progesterone concentrations in blow varied by reproductive status; pregnant females (410.6±87.8pg/ml) and females in the luteal phase of the estrous cycle (339.5±51.0pg/ml) had higher (p<0.0001) blow progesterone concentrations than non-pregnant females without a corpus luteum (242.5±27.3pg/ml). Results indicate that blow sample analysis can be used to detect variation in reproductive states associated with large differences in circulating testosterone or progesterone in belugas.

Virus-associated papillomatous skin lesions in a giant guitarfish Rhynchobatus djiddensis: a case report.

Although elasmobranch species are increasingly displayed in public aquaria, knowledge of disease in wild and captive elasmobranchs, as well as the agents involved, remains limited, and descriptions are often incomplete. This report describes papillomatous skin lesions in a juvenile giant guitarfish Rhynchobatus djiddensis associated with intranuclear viral particles. Skin biopsies were collected from multiple, friable, raised, villonodular skin lesions affecting pigmented and non-pigmented skin of the caudal fin and ventrum, respectively. Microscopic examination revealed papillary proliferation of the epidermis, with widespread marked karyomegaly of squamous epithelial cells. In approximately 75% of nuclei, chromatin was marginated by one to multiple, large, amphophilic inclusions. Large numbers of unencapsulated, 75 nm, icosahedral viral particles were observed to form large arrays in affected nuclei using transmission electron microscopy. Based on intranuclear location, particle size and morphology, a consensus nested-PCR for adenovirus polymerase was attempted. However, no adenoviral gene sequence was amplified. The nature of the involved virus remains unknown and an ongoing area of investigation. Lesions regressed completely over a 6 mo period, during which time the animal showed no signs of systemic illness, and there has been no recrudescence for 6 mo following resolution. Two cohorts of similar age and in close contact with the case animal were unaffected.

MEDICAL MANAGEMENT OF COELOMIC DISTENTION, ABNORMAL SWIMMING, SUBSTRATE RETENTION, AND HEMATOLOGIC CHANGES IN A REEF MANTA RAY (MANTA ALFREDI).

An adult, female, reef manta ray (Manta alfredi) was evaluated for abnormal swimming and coelomic distention after colliding with a floating dock in an exhibit. Initial clinical signs included abnormal posture and swimming. Clinical signs progressed to include muscle wasting, poor body condition, and coelomic distention. Further diagnostics revealed excessive exhibit substrate within the gastrointestinal tract, gastric ulcers, free coelomic fluid, possible spinal lesion, possible uterine abnormality, and hematologic changes. The ray was treated with repeated gastroscopic examinations to remove substrate from the stomach. Psyllium and mineral oil were administered in gel food to assist with passage of substrate through the gastrointestinal tract. Gastric ulcers were treated with sucralfate. Vitamin B complex, iron dextran, and Yunnan Paiyao were used to treat the anemia. Amikacin and sulfadimethoxine-ormetoprim were administered for suspected bacterial and coccidial infections, respectively. Over the course of 11 mo the ray returned to normal health.

COMPARISON OF PRE- AND POSTQUARANTINE BLOOD CHEMISTRY AND HEMATOLOGY VALUES FROM WILD-CAUGHT COWNOSE RAYS (RHINOPTERA BONASUS).

Though one of the most widely kept elasmobranchs in human care, the cownose ray (CNR; Rhinoptera bonasus ), remains a species with minimal published information on hematologic reference intervals. As part of a larger study investigating the health and nutrition of the CNR, this study established a preliminary data set of plasma chemistry and hematology values specific to animals recently caught from the wild and compared this data set (intake sample) to values obtained following a period of quarantine (27-40 days) in an aquarium (exit sample). Blood samples were collected from 47 wild female (n = 46) and male (n = 1) CNR caught in pound nets off the coast of North Carolina and South Carolina. Differences between intake and exit values were analyzed. Due to the preponderance of female animals, data were not analyzed for sex differences. Plasma biochemical profiles were performed and analyzed. A select number of complete blood cell counts were performed (n = 24 from 12 animals). Statistically significant differences (P < 0.05) specific to time of sampling were determined for packed cell volume, total solids, blood urea nitrogen, sodium, chloride, potassium, phosphorus, cholesterol, glucose, and aspartate aminotransferase. Values reported are a significant expansion on the existing limited data for CNRs and will serve as a reference for health assessment of individuals both in the wild and in exhibit populations.

Right Heart Failure in an African Penguin ( Spheniscus demersus ).

A 19-year-old male African penguin ( Spheniscus demersus ) was presented with coelomic distention after a 6-week history of lethargy and decreased appetite. Results of radiographs showed loss of coelomic detail, and ultrasound and computed tomography results revealed coelomic fluid and dilated hepatic veins. Echocardiography revealed moderate right atrial enlargement. Findings were consistent with right-sided cardiac disease. Treatment with furosemide initially reduced ascites, but the clinical condition worsened weeks later and enalapril, pimobendan, and sildenafil were added to the medical therapy. At 12 weeks after presentation, results of an echocardiogram revealed persistent right atrioventricular valve regurgitation, moderate ascites, and dilation of hepatic veins. Clinical signs of right heart failure were managed through adjustments in medical therapy and coelomic fluid aspiration, but the bird died 18 weeks after initial presentation. Gross and microscopic findings were consistent with valvular insufficiency and right-sided heart failure. To our knowledge, this case is the first documented report of cardiac disease in an African penguin.

Modified-closed castration: a novel technique for sea otter (Enhydra lutris nereis) orchiectomies.

A novel surgical technique was used in the routine castrations of two intact male southern sea otters, Enhydra lutris nereis, housed at the Georgia Aquarium (Atlanta, Georgia, USA). This technique involved incising the parietal vaginal tunic to allow placement of double ligation of the ductus deferens, testicular artery, and pampiniform plexus en masse. After ligating and transecting these structures, they were introduced back into the tunic, which was closed with a circumferential ligature. The incision site was closed in a routine manner. Both otters recovered well from the procedure. One otter had mild cutaneous dehiscence postoperatively, and the other had no obvious complications. Benefits of this procedure include reduced risk of ligature slippage or loosening and resultant hemorrhage, as provided by the traditional open portion of the castration, and decreased postoperative swelling, as provided by the closed part of the castration. To the authors' knowledge, this is the first time this technique has been described for use in sea otters.

Protein and cholesterol electrophoresis of plasma samples from captive cownose ray (Rhinoptera bonasus).

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.