Water temperature fluctuations as a key driver of cetacean pox (tattoo) lesions in bottlenose dolphins Tursiops truncatus.

Dolphin tattoo lesions are superficial non-raised skin lesions caused by poxviruses. Their presentation can vary but typical lesions in bottlenose dolphins are circular to ovoid with concentric rings of black stippling. These lesions have at times been suggested as an indicator of overall dolphin health and welfare. This study explored the effect of water temperature on the extent of tattoo lesions in 25 dolphins, along with established hematological health parameters and food consumption. Study animals consisted of 9 males and 16 females with dolphin tattoo lesions ranging in age from 2 to 45 yr. A significant decrease (p < 0.01) in extent and appearance of tattoo lesions was documented following increase in water temperature from 21-24°C (70-75°F) to 25.5-26.5°C (78-80°F). Reduction in tattoo lesions could be noted as early as 2-3 wk following water temperature increase. Marked reduction to complete resolution of tattoo lesions was reproducibly seen 5-6 wk post temperature increase. Food consumption following temperature increase was variable: decrease in intake was noted in 48% of dolphins, increase in intake in 52%. Routine blood parameters (complete blood count, serum chemistry panel, fibrinogen, erythrocyte sedimentation rate) remained within normal limits. A significant increase (p < 0.05) in extent and appearance of tattoo lesions was documented in 3 dolphins as early as 4-5 wk following a decrease in water temperature from 26.1°C (79°F) to 21°C (70°F). Water temperature is a key environmental parameter affecting cetacean pox ('tattoo') lesions in bottlenose dolphins. The absence of changes in hematological parameters along with lack of correlation between extent of pox lesions and food intake indicates that dolphin tattoo lesions are not an appropriate indicator of overall health.

EVALUATION OF PLASMA 25-HYDROXYVITAMIN D, IONIZED CALCIUM, AND PARATHYROID HORMONE IN GREEN SEA TURTLES (CHELONIA MYDAS) EXPOSED TO DIFFERENT INTENSITIES OF ULTRAVIOLET B RADIATION.

For many reptile species, adequate ultraviolet B (UVB) radiation is essential for proper calcium metabolism. In this study, the effects of UVB radiation on calcium metabolism were evaluated in green sea turtles (Chelonia mydas). 25-Hydroxyvitamin D, parathyroid hormone (PTH), and ionized calcium (iCa) were measured in juvenile (n = 18, 9 indoor, 9 outdoor) and adult (n = 8, 4 indoor, 4 outdoor) turtles. All animals were fed an identical diet. Outdoor animals had access to unfiltered sunlight, whereas indoor animals were housed under artificial lighting without UVB. Mean values for 25-hydroxyvitamin D for the outdoor and indoor groups were 34.33 ± 7.98 nmol/L and 7.11 ± 1.69 nmol/L for juveniles and 73.25 ± 30.34 nmol/L and 14.0 ± 11.52 nmol/L for adults respectively. Mean values for iCa for the outdoor and indoor groups were 0.98 ± 0.07 mmol/L and 0.99 ± 0.06 mmol/L for juveniles and 1.18 ± 0.22 mmol/L and 0.97 ± 0.18 mmol/L for adults respectively. UVB exposure (P < 0.001) and age (P < 0.001) had a significant effect on 25-hydroxyvitamin D as well as a significant interaction between the two variables (P = 0.008), with highest values in adult outdoor turtles. There was a significant interaction between age group and UVB status for iCa (P = 0.036), with greater values in older outdoor turtles. 25-Hydroxyvitamin D and total calcium were positively correlated, rs = 0.39, P = 0.042. iCa and calcium-to-phosphorus ratios were also positively correlated, rs = 0.42, P = 0.027. These results suggest that UVB exposure is an important source of 25-hydroxyvitamin D for green sea turtles and has significant effects on calcium metabolism in this species. PTH values in this study were near the minimum limits of detection and suggest that current mammalian-based PTH assays are not valid for reptiles.

Population Pharmacokinetics of Danofloxacin After Single Intramuscular Dose Administration in California Brown Pelicans (Pelecanus occidentalis californicus).

The pharmacokinetics of danofloxacin was investigated in rehabilitated California brown pelicans (Pelecanus occidentalis californicus) after a single intramuscular injection at a dose of 15 mg/kg body weight. The concentration of the drug in plasma was assayed by high-pressure liquid chromatography. A sparse-sampling design was used to reduce the number of samples (1-4 venipunctures) obtained from 24 brown pelicans. A population pharmacokinetic analysis with nonlinear mixed-effects modeling was used to accommodate the sparse-sampling strategy. The nonlinear mixed-effects modeling approach measured both fixed effects (typical values for the population) and random effects (between-subject variability) for this population. A 1-compartment model best represented the concentration-versus-time data after injection. After injection, the elimination half-life, peak concentration, area under the curve, and volume of distribution were 2.76 hours, 2.5 µg/mL, 13.75 µg/h/mL, and 4.35 L/kg, respectively. Rate of absorption was highly variable among the birds. The intramuscular injection of danofloxacin in pelicans at this dose produced plasma concentrations that meet therapeutic targets for bacteria with a minimum inhibitory concentration of ≤0.25 µg/mL. This dose can be used for future studies to evaluate the efficacy of danofloxacin for treating susceptible bacteria.

SERUM COBALAMIN AND FOLATE CONCENTRATIONS AS INDICATORS OF GASTROINTESTINAL DISEASE IN KILLER WHALES ( ORCINUS ORCA).

Cobalamin and folate are water-soluble vitamins that are useful indicators of chronic gastrointestinal (GI) function in humans and some animal species. Serum cobalamin and folate concentrations in an ex situ population of killer whales ( Orcinus orca) were measured and factors that may affect their serum concentrations were identified. Serum samples ( n = 104) were analyzed from killer whales ( n = 10) both while clinically healthy and during periods of clinical GI disease as defined by clinical signs and fecal cytology. To characterize serum cobalamin and folate concentrations in clinically healthy animals, a mixed-model regression was used, with cobalamin and folate both significantly affected by weight (cobalamin: P < 0.0001, folate: P = 0.006) and season (cobalamin: P < 0.0001, folate: P < 0.0001). The marginal mean concentrations for cobalamin and folate across weight and season were 742 ± 53.6 ng/L and 30.2 ± 2.6 µg/L, respectively. The predicted 95% confidence intervals (CI) for these analytes were then compared with samples collected during periods of GI disease. Across individuals, 22% (2/9) of the folate and 80% (8/10) of the cobalamin samples from the animals with GI disease fell outside the 95% CI for the population. When comparing samples within an individual, a similar pattern presented, with 100% of cobalamin of the observed abnormal samples reduced compared to healthy animal concentration variability. The same was not true for folate. These results suggest that serum concentrations of cobalamin and folate may be useful minimally invasive markers to identify GI disease in killer whales, especially when values are compared within an individual.

ESTABLISHING MARGINAL LYMPH NODE ULTRASONOGRAPHIC CHARACTERISTICS IN HEALTHY BOTTLENOSE DOLPHINS ( TURSIOPS TRUNCATUS).

Pulmonary disease has been well documented in wild and managed dolphin populations. The marginal lymph nodes of the dolphin thorax provide lymphatic drainage to the lungs and can indicate pulmonary disease. This study standardized a technique for rapid, efficient, and thorough ultrasonographic evaluation of the marginal lymph nodes in bottlenose dolphins ( Tursiops truncatus). Thoracic ultrasonography was performed on 29 clinically healthy adult bottlenose dolphins. Reference intervals for lymph node dimensions and ultrasonographic characteristics of marginal lymph nodes were determined from four transducer orientations: longitudinal, transverse, oblique, and an orientation optimized to the ultrasonographer's eye. The relationship between lymph node dimensions and dolphin age, sex, length, weight, origin, and management setting (pool versus ocean enclosure) were also evaluated. The mean marginal lymph nodes measured 5.26 cm in length (SD = 1.10 cm, minimum = 3.04 cm, maximum = 7.61 cm, reference interval [10th to 90th percentiles per node dimension] 3.78-6.55 cm) and 3.72 cm in depth (SD = 0.59 cm, minimum = 2.64, maximum = 5.38 cm, reference interval 2.98-4.50 cm). Sex, dolphin length, weight, and management setting had no effect on lymph node dimensions. Dolphins >30 yr of age had longer node lengths than dolphins 5-10 yr old. Node dimensions did differ between dolphins from various origins. Most commonly, the lymph node was found to be hyperechoic relative to surrounding soft tissues (98%) and to have irregular caudal borders (84%), ill-defined deep borders (83%), flat superficial border (67%), triangular or rounded triangle shape (59%), irregular cranial border (55%), and moderate heterogeneity (34%). The data reported in this study serve as a baseline reference that may contribute to earlier detection of pleural and pulmonary disease of managed and wild cetacean populations.

Evaluation of anti-Erysipelothrix rhusiopathiae IgG response in bottlenose dolphins Tursiops truncatus to a commercial pig vaccine.

Erysipelothrix rhusiopathiae is the causative agent of erysipeloid in humans and of erysipelas in various animals, including bottlenose dolphins Tursiops truncatus, in which an infection has the potential to cause peracute septicemia and death. The purpose of this study was to evaluate the efficacy of using an off-label porcine (ER BAC PLUS®, Zoetis) E. rhusiopathiae bactrin in a bottlenose dolphin vaccination program by determining the anti-E. rhusiopathiae antibody levels in vaccinated dolphins over a 10 yr period. Serum samples (n = 88) were analyzed using a modified fluorescent microbead immunoassay from 54 dolphins, including 3 individuals with no history of vaccination and 51 dolphins with an average of 5 vaccinations, 3 of which had previously recovered from a natural E. rhusiopathiae infection. A mean 311-fold increase in the immunoglobulin G (IgG) antibody index was measured in a subsample of 10 dolphins 14 d after the first booster vaccination. Serum IgG antibody titers were influenced by number of vaccines received (r2 = 0.47, p < 0.05) but not by age, gender, history of natural infection, adverse vaccine reaction, vaccination interval or time since last vaccination. The commercial pig bacterin was deemed effective in generating humoral immunity against E. rhusiopathiae in dolphins. However, since the probability of an adverse reaction toward the vaccine was moderately correlated (p = 0.07, r2 = 0.1) with number of vaccines administered, more research is needed to determine the optimal vaccination interval.

Cutaneous malignant melanoma in a Haller's round ray Urobatis halleri.

Multiple black raised nodular masses were noted on the dorsal surface of an adult male Haller's round ray Urobatis halleri. Biopsy of 2 masses was performed, and histopathology revealed proliferative sheets of melanocytes exhibiting mild anisocytosis and anisokaryosis, supporting a diagnosis of malignant melanoma. Approximately 2 mo following the biopsy procedure, the round ray became acutely anorexic and was found dead in its enclosure. A full necropsy was performed, and tissues were submitted for histopathology. The black raised nodular masses again exhibited histologic features of a melanoma. In addition to the nodular masses present, multiple flat areas of increased pigmentation were also present throughout the course of the case and were not suggestive of neoplasia histologically. The transformation of benign to malignant neoplasia has been well described in other species and may have played a role in the development of multiple tumors in this case.

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

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.

MALE REPRODUCTIVE PHYSIOLOGY AND THE DEVELOPMENT OF ARTIFICIAL INSEMINATION IN THE MAGELLANIC PENGUIN (SPHENISCUS MAGELLANICUS) USING CHILLED-STORED SEMEN.

Research was performed to increase our understanding of male Magellanic penguin (Spheniscus magellanicus) reproductive biology and to develop artificial insemination (AI) technology to assist with maintaining the species' genetic diversity. Seminal traits were characterized from seven males with noncontaminated ejaculates (n = 123) displaying high in vitro motion parameters, membrane integrity, and morphology. Seven females were maintained in nest sites that permitted visual, auditory, and tactile contact with their paired male but not copulation for 18.3 ± 2.4 days before egg lay. After cloacal AI (2.6 ± 0.4 inseminations/female) with semen chilled for up to 20.5 hr at 5°C, all females produced one to two fertile eggs, with the first oviposition occurring within 7 days of plasma progesterone concentrations exceeding 0.8 ng/ml. Overall fertility was 91.7%, hatchability was 63.6%, and genetic analyses confirmed that all embryos and hatchlings were sired by AI males. The heterospermic AI design demonstrated that eggs were fertilized by spermatozoa chilled for 1.5-19.8 hr before AI and were laid 4.5-11.5 days post AI. These results contribute new data on Magellanic penguin sperm biology and demonstrate that high fertility rates after AI of chilled semen can be achieved with females remaining in proximity to their paired mate.

CHARACTERIZATION OF A FOLLICULAR CELL CARCINOMA OF THE THYROID IN A YELLOWBAR ANGELFISH (POMACANTHUS MACULOSUS).

Histopathologic diagnosis of thyroid neoplasia in teleosts is complicated, because thyroid tissue is unencapsulated, and normal tissue can have wide ectopic extensions. Assessment of thyroid hormone concentrations in conjunction with histologic evaluation of thyroid carcinoma has not been reported in teleosts, even though routinely performed in other species. A yellowbar angelfish (Pomacanthus maculosus) presented with a mass that extended beyond the gill arches. Partial surgical resection was performed, and a histologic diagnosis of thyroid carcinoma was made. Plasma from the affected fish and two control Pomacanthus were used to assess thyroid hormone concentrations using a domestic mammalian assay. Thyroid-stimulating hormone and throxine were undetectable in two of three fish. Triiodothyronine was lower in the affected fish than in controls. The tumor did not appear to be actively secreting hormone. This is the first characterization of thyroid tumors and corresponding thyroid hormones in teleosts, which may assist in diagnosis of this disease.

APHAKIC PHACOEMULSIFICATION AND AUTOMATED ANTERIOR VITRECTOMY, AND POSTRETURN MONITORING OF A REHABILITATED HARBOR SEAL (PHOCA VITULINA RICHARDSI) PUP.

A female harbor seal pup rescued along the coast of San Diego on 13 June 2012 was diagnosed with bilateral mature cataracts, apparently congenital, in association with vitreal herniation in the anterior chamber of each eye. The cataracts were surgically removed on 1 August 2012 with single-port aphakic phacoemulsification and automated anterior vitrectomy. Postoperative monitoring during the next several weeks indicated that vision had been functionally repaired and that she could visually orient to and capture live fish in three different environments and in the presence of other animals. Consequently, we equipped the seal with a satellite-linked radio transmitter and returned her to the Pacific Ocean on 21 November 2012, and then monitored her movements until radio contact ended on 2 March 2013. She remained along the San Diego coast from 21 November until 5 December 2012 when she relocated to the Coronado Islands and remained there until 26 December. She then traveled directly to San Clemente Island and remained foraging in the near-shore kelp beds there through 2 March 2013, when radio contact ended. To our knowledge, this is the first published report of cataract treatment in a marine mammal using high-frequency ultrasound to emulsify the lenses followed by suction removal of the emulsified microfragments (i.e., phacoemulsification). Moreover, the rapid postoperative recovery of the seal and its quick acclimation, orientation, navigation, and foraging in marine habitats after return to the Pacific Ocean indicates that these surgical procedures can be safe and effective treatments for cataracts in seals, with substantially reduced postsurgical complications relative to other types of lens fragmentation and removal procedures.

VORICONAZOLE TOXICITY IN MULTIPLE PENGUIN SPECIES.

Aspergillosis is a common respiratory fungal disease in penguins managed under human care. Triazole antifungal drugs, including itraconazole, are most commonly used for treatment; however, itraconazole treatment failures from drug resistance are becoming more common, requiring newer treatment options. Voriconazole, a newer triazole, is being used more often. Until recently, no voriconazole pharmacokinetic studies had been performed in penguins, leading to empiric dosing based on other avian studies. This has led to increased anecdotal reporting of apparent voriconazole toxicity in penguins. This report describes 18 probable and 6 suspected cases of voriconazole toxicity in six penguin species from nine institutions: 12 African penguins (Spheniscus demersus), 5 Humboldt penguins (Spheniscus humboldti), 3 Magellanic penguins (Spheniscus magellanicus), 2 gentoo penguins (Pygoscelis papua papua), 1 macaroni penguin (Eudyptes chrysolophus), and 1 emperor penguin (Aptenodytes forsteri). Observed clinical signs of toxicity included anorexia, lethargy, weakness, ataxia, paresis, apparent vision changes, seizure-like activity, and generalized seizures. Similar signs of toxicity have also been reported in humans, in whom voriconazole therapeutic plasma concentration for Aspergillus spp. infections is 2-6 µg/ml. Plasma voriconazole concentrations were measured in 18 samples from penguins showing clinical signs suggestive of voriconazole toxicity. The concentrations ranged from 8.12 to 64.17 µg/ml, with penguins having plasma concentrations above 30 µg/ml exhibiting moderate to severe neurologic signs, including ataxia, paresis, and seizures. These concentrations were well above those known to result in central nervous system toxicity, including encephalopathy, in humans. This case series highlights the importance of species-specific dosing of voriconazole in penguins and plasma therapeutic drug monitoring. Further investigation, including pharmacokinetic studies, is warranted. The authors recommend caution in determining voriconazole dosages for use in penguin species.

Pharmacokinetics of single dose oral meloxicam in bottlenose dolphins (Tursiops truncatus).

The objective of this study was to investigate the pharmacokinetics of meloxicam in bottlenose dolphins (Tursiops truncatus). Ten adult bottlenose dolphins were used for the study. Each animal received a single oral dose of meloxicam at 0.1 mg/kg. Two to seven serial blood samples were collected per animal, at one of fourteen time points between T = 0 and T = 240 hr. Complete blood count and serum chemistry analysis were performed prior to drug administration, as well as at the final time point for each individual. Plasma drug concentrations were determined by high-pressure liquid chromatography. No adverse hematological, biochemical or clinical changes were noted during the study period. After oral administration, a peak plasma concentration of 1.03 microg/mL was achieved at approximately 11 hr. This suggests that a single oral dose of 0.1 mg/kg provides a peak plasma level similar to what is considered therapeutic in other species. However, the elimination of meloxicam in cetaceans was slower than in other species, with an elimination half-life of almost 70 hr, and detectable drug concentrations up to 7 days. A single oral dose of 0.1 mg/kg appears safe for use in this species, but caution in repeated dosing must be used, due to the prolonged elimination, until multi-dose pharmacokinetic studies are determined.

Laparoscopic Evaluation of the Reproductive Tract in Two Female Polar Bears (Three Procedures) (Ursus maritimus).

Polar bears (Ursus maritimus) face a number of challenges that threaten the survival of the species. Captive breeding represents one essential facet of species conservation, but aspects of the polar bear's reproductive physiology, such as follicle maturation, coitus-induced ovulation, and pseudopregnancy, are poorly characterized and present challenges for enhancing natural reproductive success and the application of advanced reproductive techniques. Due to the absence of a reliable transrectal or transabdominal ultrasound method for ovarian examination in the species, the ovaries of two adult female polar bears were examined laparoscopically to evaluate the feasibility of surgical access to the ovaries, oviduct, and uterus. The minimally invasive procedure was easily and rapidly performed in both bears and all procedures. Direct visual assessment of the ovary was possible after dissection of a fatty bursal sac, which completely enclosed the ovaries. In the second bear, laparoscopic manipulation of the ovary to draw it closer to the body wall enabled transcutaneous ultrasound. Laparoscopy may be a valuable tool to aid in the application of advanced reproductive technologies in polar bears.

Hematological and serum biochemical analytes reflect physiological challenges during gestation and lactation in killer whales (Orcinus orca).

Gestation and lactation result in metabolic alterations of the dam because of varying demands of the fetus and offspring during the different stages of development. Despite killer whales (Orcinus orca) having one of the longest gestations and highest birth weights of all mammals in human care, these metabolic alterations, and their impact on the physiology of the dam have not been measured. The objectives of this analysis were to determine if physiologic demands on the killer whale during pregnancy and lactation have measurable effects on hematology and biochemical analytes and if detectable, to compare these changes to those which are observed in other mammalian species. Forty hematologic and biochemical analytes from seven female killer whales (22 pregnancies, 1,507 samples) were compared between the following stages: (1) non-pregnant or lactating (control); (2) gestation; and (3) the first 12 months of lactation. Decreased hematocrit, hemoglobin, and red blood cell counts were indicative of plasma volume expansion during mid and late gestation. The killer whales exhibited a progressively increasing physiologic inflammatory state leading up to parturition. Gestation and lactation caused significant shifts in the serum lipid profiles. Gestation and lactation cause significant physiologic changes in the killer whale dam. The last 12 months of gestation had greater physiological impact than lactation, but changes associated with and immediately following parturition were the most dramatic. During this period, killer whales may experience increased susceptibility to illness, and anthropogenic and environmental disturbances.

Discovery of an orthoreovirus in the aborted fetus of a Steller sea lion (Eumetopias jubatus).

An aborted mid-gestational male Steller sea lion fetus with an attached placenta was recovered on the floor of an open floating capture trap located off Norris Rock near Denman Island, British Columbia. Viral culture of the placenta demonstrated cytopathic effect. Although no specific signal was obtained in microarray experiments using RNA obtained from viral culture, elution and sequence analysis revealed the presence of a reovirus. Complete genome pyrosequencing led to the identification of an orthoreovirus that we have tentatively named Steller sea lion reovirus (SSRV). Phylogenetic analysis revealed similarities between SSRV and orthoreoviruses of birds, bats and other mammals that suggests potential for interspecies transmission.

A Comparison of Parapoxviruses in North American Pinnipeds.

Parapoxviruses cause nodular lesions on the skin and mucosal membranes of pinnipeds and infections by these viruses have been documented worldwide. Seal parapoxvirus is currently classified as a tentative species of the Parapoxvirus genus. Tissue or swab samples were analyzed from 11 pinnipeds of different host species undergoing rehabilitation on the east and west coasts of the United States of America (USA) that were positive for parapoxvirus. The aim of the study was to compare parapoxvirus sequences of fragments of the B2L, DNA polymerase, GIF and viral interleukin-10 ortholog (vIL-10) genes and to examine the evolutionary relationship between viruses detected in different pinniped species and at different locations with other members of the Parapoxvirus genus, such as Orf virus (ORFV), Bovine papular stomatitis virus (BPSV) and Pseudocowpox virus (PCPV). The sequence analysis showed that the parapoxvirus sequences from the pinnipeds differed significantly from those found in terrestrial hosts and that they formed a separate cluster within the genus. Our results suggest that transmission of the same parapoxvirus strain is possible between different species, including between members of different families (phocids and otariids). Animals belonging to the same species but living in distant geographic locations presented genetically distant parapoxviruses. The findings of this study demonstrate that sealpox lesions in pinnipeds of different species are caused by viruses that belong to the Parapoxvirus genus but have significant genetic differences compared to the established virus species in terrestrial hosts, thus strongly supporting the classification of pinniped parapoxvirus as a new species of the genus.

Characterization of phylogenetically diverse astroviruses of marine mammals.

Astroviruses are small, non-enveloped, positive-stranded RNA viruses. Previously studied mammalian astroviruses have been associated with diarrhoeal disease. Knowledge of astrovirus diversity is very limited, with only six officially recognized astrovirus species from mammalian hosts and, in addition, one human and some bat astroviruses were recently described. We used consensus PCR techniques for initial identification of five astroviruses of marine mammals: three from California sea lions (Zalophus californianus), one from a Steller sea lion (Eumetopias jubatus) and one from a bottlenose dolphin (Tursiops truncatus). Bayesian and maximum-likelihood phylogenetic analysis found that these viruses showed significant diversity at a level consistent with novel species. Astroviruses that we identified from marine mammals were found across the mamastrovirus tree and did not form a monophyletic group. Recombination analysis found that a recombination event may have occurred between a human and a California sea lion astrovirus, suggesting that both lineages may have been capable of infecting the same host at one point. The diversity found amongst marine mammal astroviruses and their similarity to terrestrial astroviruses suggests that the marine environment plays an important role in astrovirus ecology.

Polyomavirus infection in a free-ranging California sea lion (Zalophus californianus) with intestinal T-cell lymphoma.

An adult female California sea lion (Zalophus californianus) that stranded in central California was found to have a small glossal polypoid mass on gross necropsy. Histologically, the mass was consistent with a fibropapilloma, and intranuclear inclusions were found within endothelial cells lining small arterioles within the mass. Electron microscopy revealed 40-nm virions within endothelial intranuclear inclusions. Rolling circle amplification was used to obtain a partial viral genomic sequence. Sequence analysis identified the virus as a novel polyomavirus, tentatively named California sea lion polyomavirus 1. In addition, the sea lion had a severely thickened small intestine and swollen pale kidneys on gross examination. Severe renal amyloidosis with chronic interstitial nephritis was diagnosed histologically as well as T-cell intestinal lymphoma, which was confirmed via immunophenotyping and molecular clonality. The relationship, if any, between polyomavirus infection and the other disease processes in this sea lion is not known, but it is considered unlikely that the polyomavirus induced the lymphoma.

Detection of a respiratory coronavirus from tissues archived during a pneumonia epizootic in free-ranging Pacific harbor seals Phoca vitulina richardsii.

In June 2000, 21 adult harbor seals Phoca vitulina richardsii were found dead along a localized section of the central California coast. Necropsy of 5 fresh carcasses revealed pulmonary congestion, consolidation, and hemorrhage. Histopathological changes in lungs from 2 of these seals included a necrotizing lymphocytic and histocytic lobar pneumonia with intra-lesional bacteria. A coronavirus (CoV) was detected in archived tissues from 1 of the 5 seals via a degenerate PCR for nidoviral RNA-dependent RNA polymerase (RdRp), and was subsequently confirmed via specific PCR. Based on the partial RdRp sequence, the CoV was identified as a novel, divergent member of the CoV group 1a. The virus is tentatively named harbor seal coronavirus (HSCoV). The clinical significance of HSCoV and its involvement in the etiology of the epizootic pneumonia and deaths of the harbor seals is uncertain.