In 2006, a marked increase in harbor porpoise Phocoena phocoena strandings were reported in the Pacific Northwest of the USA, resulting in the declaration of an unusual mortality event (UME) for ...Washington and Oregon to facilitate investigation into potential causes. The UME was in place during all of 2006 and 2007, and a total of 114 porpoises stranded during this period. Responders examined 95 porpoises; of these, detailed necropsies were conducted on 75 animals. Here we review the findings related to this event and how these compared to the years immediately before and after the UME. Relatively equal numbers among sexes and age classes were represented, and mortalities were attributed to a variety of specific causes, most of which were categorized as trauma or infectious disease. Continued monitoring of strandings during 4 yr following the UME showed no decrease in occurrence. The lack of a single major cause of mortality or evidence of a significant change or event, combined with high levels of strandings over several post-UME years, demonstrated that this was not an actual mortality event but was likely the result of a combination of factors, including: (1) a growing population of harbor porpoises; (2) expansion of harbor porpoises into previously sparsely populated areas in Washington's inland waters; and (3) a more well established stranding network that resulted in better reporting and response. This finding would not have been possible without the integrated response and investigation undertaken by the stranding network.
Anesthesia and surgery in cetaceans have inherent risks and have rarely been utilized as viable treatment options. This report represents the first known multidisciplinary team approach to emergency ...laparotomy in a compromised, 22-yr-old, female Pacific white-sided dolphin (Lagenorhynchus obliquidens). The inciting clinical signs and ancillary diagnostics were consistent with a mechanical ileus. Although no torsion or obstruction was apparent during surgery, severe enteritis and peritonitis were noted. Postoperatively, the animal was maintained on aggressive medical management with continuous supportive care until succumbing 3 days later with clinical pathology indicative of terminal sepsis and profound inflammation. Postmortem findings included generalized vascular stasis and segmental intestinal volvulus with infarction. To the authors' knowledge, this is one of the most-complex surgical and anesthetic procedures performed in a cetacean. Though the outcome was unsuccessful, this case represents the aquatic veterinary community's collective advances in the ability to treat cetaceans under human care.
As part of an ongoing investigation of harbor seal (
Phoca vitulina
) mortalities within Puget Sound, Washington State, United States, between October 2007 and July 2008, 25 seal cases were submitted ...for histopathology and ancillary diagnostic testing, including additional attempted virus isolation.
In vitro
granular and refractile cytopathic effects (CPE) were consistently observed in Vero.DogSLAMtag cells inoculated with tissue homogenates from three seals. Transmission electron microscopy of infected Vero.DogSLAMtag cells revealed cytoplasmic clusters of icosahedral viral particles morphologically consistent with members of the family
Reoviridae
. The complete genome of a novel species within the genus
Orthoreovirus
, tentatively named phocid orthoreovirus 1 (PhRV1), was determined by next-generation sequencing and confirmed by rt-PCR in isolates from the three harbor seals. This is the first report of an orthoreovirus infection associated with dead stranded harbor seals. Aside from the CPE and ultrastructural findings, no consistent signalment, gross pathology, histopathology, or ancillary diagnostic findings were identified with PhRV1 infection. Further research is needed to determine the prevalence, tissue tropism, transmission, pathogenicity, zoonotic potential, and host range of orthoreoviruses in pinnipeds. This study demonstrates the value of thorough necropsy investigations and a multidisciplinary team approach to advance our understanding of marine mammal health.
The seal picornavirus 1, species
Aquamavirus A
, is currently the only recognized member of the genus
Aquamavirus
within the family
Picornaviridae
. The bear picornavirus 1 was recently proposed as ...the second species in the genus under the name aquamavirus B. Herein, we determined the complete genomes of two novel pinniped picornaviruses, the harbor seal picornavirus (HsPV) and the ribbon seal picornavirus (RsPV). The HsPV and the RsPV were isolated in Vero.DogSLAMtag cells from samples collected from stranded harbor (
Phoca vitulina
) and ribbon (
Histriophoca fasciata
) seals. RsPV-infected Vero.DogSLAMtag cells displaying extensive cytopathic effects were processed for transmission electron microscopy and revealed non-enveloped viral particles aggregated into paracrystalline arrays in the cytoplasm. A next-generation sequencing approach was used to recover the complete genomes of the HsPV and the RsPV (6,709 and 6,683 bp, respectively). Phylogenetic and genetic analyses supported the HsPV and the RsPV as members of the
Aquamavirus
genus. Based on these results, RsPV represents a novel strain of
Aquamavirus A
, while the HsPV is a novel strain of the proposed species aquamavirus B. These discoveries provide information on the evolutionary relationships and ultrastructure of aquamaviruses and expands the known host range of those viruses. Our results underscore the importance of the application of classical virology and pathology techniques coupled with high-throughput sequencing technologies for the discovery and characterization of pathogens in wild marine mammals.
Leptospirosis, caused by the spirochete Leptospira, is a geographically widespread disease that affects a broad range of mammals, including marine mammals. Among pinniped populations, periodic ...epizootics of leptospirosis are responsible for significant die-offs. Along the west coast of North America, the most recent leptospirosis epizootic occurred in 2004, during which samples were collected from cases ranging from California to British Columbia. The primary objective of this study was to use this well-defined sample set to determine the feasibility of using PCR techniques to diagnose Leptospira infection among pinniped populations in comparison with diagnostic methodologies commonly used for marine mammals. Successful amplification was achieved from a variety of samples, including freshly collected urine, urine stored at -80°C for less than 6 months, and kidney (freshly collected, frozen, and decomposed), as well as feces- and urine-contaminated sand collected in the vicinity of a live-stranded animal. Pathological examination of tissue collected from Leptospira-infected animals revealed the presence of leptospiral antigen in the kidneys. The use of species-specific primer pairs revealed a pattern of host specificity for Leptospira interrogans in sea lions and Leptospira kirschneri in elephant seals. These studies indicate PCR is a sensitive and specific diagnostic tool for the detection of Leptospira infection in pinnipeds and reveal a potential source for epizootic, enzootic, and zoonotic spread of leptospirosis in a marine environment.
Polychlorinated biphenyls and other persistent organic pollutants have been associated with immunotoxicity and outbreaks of (infectious) disease in marine mammals by rendering them vulnerable to ...infection by pathogens such as viruses and bacteria. In an immunotoxicological study of free‐ranging harbor seals (Phoca vitulina), we obtained samples of blood and blubber from seal pups that were live‐captured from two remote and two near‐urban sites in British Columbia, Canada, and Washington state, USA. Using these samples, we quantified hematology, innate immune function, adaptive immune function, and polychlorinated biphenyl accumulation. While controlling for confounding factors (age, sex, and condition), univariate correlations between phagocytosis (r2 = 0.30, p = 0.002), respiratory burst (r2 = 0.45, p = 0.000), T‐lymphocyte function (r2 = 0.16, p = 0.028), lymphocyte signaling (r2 = 0.17, p = 0.025), and lymphocyte counts (r2 = 0.29, p = 0.002), and polychlorinated biphenyl concentrations suggested chemical‐associated immunotoxicity. Principal component analysis of immunological endpoints provided additional evidence of immunotoxic effects in seals. However, principal component analysis also identified a noncontaminant‐related factor by distinguishing between seals inhabiting urban versus remote sites, with results being consistent with increased pathogen exposure. Elevated fecal coliform concentrations in water, and observations of terrestrial spill‐over pathogens in local seals, further support the notion of biological pollution at these sites. Although our study highlights the role that environmental contaminants might play in rendering marine mammal populations vulnerable to disease through immunotoxicity, it also suggests that biological pollution represents an emerging conservation concern.
Fatal diphenhydramine poisoning in a dog Buchweitz, John P; Raverty, Stephen A; Johnson, Margaret B ...
Canadian veterinary journal
55, Številka:
11
Journal Article
Recenzirano
We report a fatal diphenhydramine poisoning of a 10-year-old, male poodle-cross dog with pre-existing conditions and suspected co-ingestion of ethanol. This case illustrates that diphenhydramine ...overdose can be fatal in certain circumstances and that analytical toxicology may play an important role in animal death investigations.
Q fever is a zoonotic disease caused by the bacterium Coxiella burnetii. Humans are commonly exposed via inhalation of aerosolized bacteria derived from the waste products of domesticated sheep and ...goats, and particularly from products generated during parturition. However, many other species can be infected with C. burnetii, and the host range and full zoonotic potential of C. burnetii is unknown. Two cases of C. burnetii infection in marine mammal placenta have been reported, but it is not known if this infection is common in marine mammals. To address this issue, placenta samples were collected from Pacific harbor seals (Phoca vitulina richardsi), harbor porpoises (Phocoena phocoena), and Steller sea lions (Eumetopias jubatus). Coxiella burnetii was detected by polymerase chain reaction (PCR) in the placentas of Pacific harbor seals (17/27), harbor porpoises (2/6), and Steller sea lions (1/2) collected in the Pacific Northwest. A serosurvey of 215 Pacific harbor seals sampled in inland and outer coastal areas of the Pacific Northwest showed that 34.0% (73/215) had antibodies against either Phase 1 or Phase 2 C. burnetii. These results suggest that C. burnetii infection is common among marine mammals in this region.
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