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J P Dubey - One of the best experts on this subject based on the ideXlab platform.
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recent epidemiologic and clinical importance of toxoplasma gondii infections in marine mammals 2009 2020
Veterinary Parasitology, 2020Co-Authors: J P Dubey, F H A Murata, Camila K Cerqueiracezar, O C H Kwok, Michael E GriggAbstract:Toxoplasma gondii infections are common in humans and animals worldwide. T. gondii causes mortality in several species of marine mammals, including threatened Southern sea otters (Enhydra lutris) and endangered Hawaiian monk seals (Monachus schauinslandi). Marine mammals are now considered sentinels for environmental exposure to protozoan agents contaminating marine waters, including T. gondii oocysts. Marine mammals also serve as food for humans and can result in foodborne T. gondii infections in humans. The present review summarizes worldwide information on the prevalence of clinical and subclinical infections, epidemiology, and genetic diversity of T. gondii infecting marine mammals in the past decade. The role of genetic types of T. gondii and clinical disease is discussed.
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an update on sarcocystis neurona infections in animals and equine protozoal myeloencephalitis epm
Veterinary Parasitology, 2015Co-Authors: J P Dubey, Daniel K. Howe, Martin Furr, W J A Saville, Antoinette E Marsh, S M Reed, Michael E GriggAbstract:Equine protozoal myeloencephalitis (EPM) is a serious disease of horses, and its management continues to be a challenge for veterinarians. The protozoan Sarcocystis neurona is most commonly associated with EPM. S. neurona has emerged as a common cause of mortality in marine mammals, especially sea otters (Enhydra lutris). EPM-like illness has also been recorded in several other mammals, including domestic dogs and cats. This paper updates S. neurona and EPM information from the last 15 years on the advances regarding life cycle, molecular biology, epidemiology, clinical signs, diagnosis, treatment and control.
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sarcocystis neurona retinochoroiditis in a sea otter Enhydra lutris kenyoni
Veterinary Parasitology, 2011Co-Authors: J P Dubey, Nancy J ThomasAbstract:Sarcocystis neurona is an important cause of fatal disease in sea otters in the USA. Encephalitis is the predominant lesion and parasites are confined to the central nervous system and muscles. Here we report retinochoroiditis in a sea otter (Enhydra lutris kenyoni) found dead on Copalis Beach, WA, USA. Salient lesions were confined to the brain and eye. Multifocal nonsuppurative meningoencephalitis was present in the cerebrum and cerebellum associated with S. neurona schizonts. The retina of one eye had a focus of inflammation that contained numerous S. neurona schizonts and merozoites. The focus extended from the retinal pigment epithelium inward through all layers of the retina, but inflammation was most concentrated at the inner surface of the tapetum and the outer retina. The inner and outer nuclear layers of the retina were disorganized and irregular at the site of inflammation. There was severe congestion and mild hemorrhage in the choroid, and mild hemorrhage into the vitreous body. Immunohistochemistry with S. neurona-specific polyclonal rabbit antibodies stained schizonts and merozoites. To our knowledge this is the first report of S. neurona-associated retinochoroiditis in any naturally infected animal.
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toxoplasma gondii neospora caninum sarcocystis neurona and sarcocystis canis like infections in marine mammals
Veterinary Parasitology, 2003Co-Authors: J P Dubey, Nancy J Thomas, R Zarnke, S K Wong, W Van Bonn, M Briggs, J W Davis, R Ewing, M Mense, O C H KwokAbstract:Toxoplasma gondii, Neospora caninum, Sarcocystis neurona, and S. canis are related protozoans that can cause mortality in many species of domestic and wild animals. Recently, T. gondii and S. neurona were recognized to cause encephalitis in marine mammals. As yet, there is no report of natural exposure of N. caninum in marine mammals. In the present study, antibodies to T. gondii and N. caninum were assayed in sera of several species of marine mammals. For T. gondii, sera were diluted 1:25, 1:50, and 1:500 and assayed in the T. gondii modified agglutination test (MAT). Antibodies (MAT ≥1:25) to T. gondii were found in 89 of 115 (77%) dead, and 18 of 30 (60%) apparently healthy sea otters (Enhydra lutris), 51 of 311 (16%) Pacific harbor seals ( Phoca vitulina), 19 of 45 (42%) sea lions (Zalophus californianus), 5 of 32 (16%) ringed seals (Phoca hispida ), 4o f
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biological characterisation of sarcocystis neurona isolated from a southern sea otter Enhydra lutris nereis
International Journal for Parasitology, 2000Co-Authors: David S Lindsay, Nancy J Thomas, J P DubeyAbstract:Sarcocystis neurona was isolated from the brain of a juvenile, male southern sea otter (Enhydra lutris nereis) suffering from CNS disease. Schizonts and merozoites in tissue sections of the otter’s brain reacted with anti-S. neurona antiserum immunohistochemically. Development in cell culture was by endopolyogeny and mature schizonts were first observed at 3 days postinoculation. PCR of merozoite DNA using primer pairs JNB33/JNB54 and restriction enzyme digestion of the 1100 bp product with Dra I indicated the organism was S. neurona. Four of four interferon-γ gene knockout mice inoculated with merozoites developed S. neurona-associated encephalitis. Antibodies to S. neurona but not Sarcocystis falcatula, Toxoplasma gondii, or Neospora caninum were present in the serum of inoculated mice. This is the first isolation of S. neurona from the brain of a non-equine host.
Michael E Grigg - One of the best experts on this subject based on the ideXlab platform.
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recent epidemiologic and clinical importance of toxoplasma gondii infections in marine mammals 2009 2020
Veterinary Parasitology, 2020Co-Authors: J P Dubey, F H A Murata, Camila K Cerqueiracezar, O C H Kwok, Michael E GriggAbstract:Toxoplasma gondii infections are common in humans and animals worldwide. T. gondii causes mortality in several species of marine mammals, including threatened Southern sea otters (Enhydra lutris) and endangered Hawaiian monk seals (Monachus schauinslandi). Marine mammals are now considered sentinels for environmental exposure to protozoan agents contaminating marine waters, including T. gondii oocysts. Marine mammals also serve as food for humans and can result in foodborne T. gondii infections in humans. The present review summarizes worldwide information on the prevalence of clinical and subclinical infections, epidemiology, and genetic diversity of T. gondii infecting marine mammals in the past decade. The role of genetic types of T. gondii and clinical disease is discussed.
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an update on sarcocystis neurona infections in animals and equine protozoal myeloencephalitis epm
Veterinary Parasitology, 2015Co-Authors: J P Dubey, Daniel K. Howe, Martin Furr, W J A Saville, Antoinette E Marsh, S M Reed, Michael E GriggAbstract:Equine protozoal myeloencephalitis (EPM) is a serious disease of horses, and its management continues to be a challenge for veterinarians. The protozoan Sarcocystis neurona is most commonly associated with EPM. S. neurona has emerged as a common cause of mortality in marine mammals, especially sea otters (Enhydra lutris). EPM-like illness has also been recorded in several other mammals, including domestic dogs and cats. This paper updates S. neurona and EPM information from the last 15 years on the advances regarding life cycle, molecular biology, epidemiology, clinical signs, diagnosis, treatment and control.
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transplacental toxoplasmosis in a wild southern sea otter Enhydra lutris nereis
Veterinary Parasitology, 2008Co-Authors: Patricia A. Conrad, Erick R James, Andrea E Packham, Sharon Toychoutka, Michael E GriggAbstract:In September 2004, a neonatal sea otter pup was found alive on the beach in northern Monterey Bay, CA. Efforts to locate the mother were unsuccessful. Due to a poor prognosis for successful rehabilitation, the pup was euthanized. Postmortem examination revealed emaciation, systemic lymphadenopathy and a malformation of the left cerebral temporal lobe. On histopathology, free tachyzoites and tissue cysts compatible with Toxoplasma gondii were observed in the brain, heart, thymus, liver, lymph nodes and peri-umbilical adipose. The presence of T. gondii within host tissues was associated with lymphoplasmacytic inflammation and tissue necrosis. Immunofluorescent antibody tests using postmortem serum were positive for anti-T. gondii IgM and IgG (at 1:320 and 1:1280 serum dilution, respectively), but were negative for IgG directed against Sarcocystis neurona and Neospora caninum (<1:40 each). Brain immunohistochemistry revealed positive staining for tachyzoites and tissue cysts using antiserum raised to T. gondii, but not S. neurona or N. caninum. T. gondii parasite DNA was obtained from extracts of brain and muscle by PCR amplification using the diagnostic B1 locus. Restriction enzyme digestion followed by gel electrophoresis and DNA sequencing confirmed the presence of Type X T. gondii, the strain identified in the majority of southern sea otter infections.
Melissa A. Miller - One of the best experts on this subject based on the ideXlab platform.
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helicobacter spp in necropsied southern sea otters Enhydra lutris nereis is associated with gastric ulcers and sensitive to multiple antibiotics
Frontiers in Marine Science, 2020Co-Authors: Melissa A. Miller, Francesca Batac, Megan E. Moriarty, Zeli Shen, James G Fox, Karen M OttemannAbstract:Southern sea otters (Enhydra lutris nereis) are threatened marine mustelids that commonly have gastric ulcers with secondary hemorrhage (melena) as a contributing cause of death. Although Helicobacter spp. infections are known to cause gastric ulcers and gastritis in humans and ferrets, it is unknown if the sea otter bacterium, ‘H. Enhydrae’ sp. nov., causes similar gastric pathology. Determining whether Helicobacter detection is associated with sea otter gastric pathology is the first step toward using this information to expedite diagnosis and treatment. We investigated the proportion of Helicobacter infections in 46 necropsied southern sea otters via quantitative real-time polymerase chain reaction (qPCR) of the 16S rRNA gene. Helicobacter DNA was detected in fresh-frozen and formalin-fixed gastric body and pyloric tissues using Helicobacter genus-specific 16S rRNA primers. Data from gross necropsy and histopathology were analyzed for associations between Helicobacter detection via qPCR, and presence/absence of gastric pathology. ETEST gradient strips were utilized to investigate antimicrobial minimum inhibitory concentrations for H. Enhydrae isolates. Helicobacter spp. were detected in the gastric tissue of 85% of sea otters in this study. Fresh-frozen samples were more commonly Helicobacter qPCR-positive than formalin-fixed tissue, indicating variable sensitivity of detection in relation to post-necropsy tissue processing methods. Diagnosis of gastric ulcers at necropsy was significantly associated with Helicobacter qPCR detection in gastric mucosa (P= 0.005), while age, sex, presence of melena, shark trauma, and protozoal infection were not associated (P> 0.1). H. Enhydrae strains were sensitive to clarithromycin and tetracycline in vitro at physiologically relevant concentrations. Overall, this work suggests that Helicobacter spp. might be commonly found in southern sea otters, particularly those with ulcers, and that H. Enhydrae can be treated with several commonly used anti-Helicobacter therapies.
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Mycoplasma Enhydrae sp. nov. isolated from southern sea otters (Enhydra lutris nereis).
International journal of systematic and evolutionary microbiology, 2018Co-Authors: Dmitriy V. Volokhov, Melissa A. Miller, Francesca Batac, Yamei Gao, Vladimir E. ChizhikovAbstract:Five Mycoplasma strains have been isolated from the oropharynx of southern sea otters (Enhydra lutris nereis) from the Central California Coast, USA. These strains were phenotypically and genetically characterized and compared to other established Mycoplasma species. All five strains hydrolysed arginine but not urea, but did not produce acid from glucose, and all were isolated and propagated under anaerobic and aerobic atmospheric conditions at +35–37 ˚C using either SP4 or PPLO medium supplemented with arginine. Colonies on solid medium showed a typical fried-egg appearance and transmission electron microscopy revealed a typical mycoplasma cellular morphology. Molecular characterization included assessment of the following genetic loci: 16S rRNA, 16S–23S rRNA ITS, rpoB, rpoC, polC, topIIA, tufB, arcA and smc. Complete 16S rRNA gene sequence analysis indicated that these strains were most closely related to Mycoplasma phocicerebrale , and to Mycoplasma arginini , Mycoplasma gateae and Mycoplasma canadense with nucleotide similarities of 99 and 98 %, respectively. Nucleotide analysis of other genetic loci revealed 73–91 % nucleotide similarity to the corresponding genes of the above closely related species. All five strains clustered into a distinct group on the 16S rRNA and rpoB phylogenetic trees. Serological testing via growth inhibition and metabolic inhibition tests employing antiserum to type strains of M. phocicerebrale , M. arginini , M. gateae and M. canadense failed to recognize these novel strains. Our results suggest that the strains isolated from southern sea otters represent a novel species of the genus Mycoplasma , for which the name Mycoplasma Enhydrae sp. nov. is proposed; the type strain is 6243-11T (=DSM 106704T=ATCC TSD-140T).
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Figure S1: Study location map. from Defining the risk landscape in the context of pathogen pollution: Toxoplasma gondii in sea otters along the Pacific Rim
2018Co-Authors: Tristan L. Burgess, James L. Bodkin, Michael J. Murray, Melissa A. Miller, Shawn Larson, Patricia A. Conrad, Tim M Tinker, Justin A Saarinen, Linda M. Nichol, Christine K. JohnsonAbstract:Map showing the location of all study regions for Northern sea otter (Enhydra lutris kenyoni). 1) Western Prince William Sound, Alaska; 2) Elfin Cove, Alaska; 3) Whale Bay, Alaska; 4) Nuchatlitz Inlet (Blue) and Clayoquot Sound (Green), British Columbia; 5) Olympic Peninsula, Washington. Coastal watersheds included in the study are outlined in black. See Figure 1 for Southern sea otter (E. lutris nereis) study regions in California
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first report of an adult tapeworm cestoda diphyllobothriidea in a southern sea otter Enhydra lutris nereis
Journal of Wildlife Diseases, 2017Co-Authors: Colleen Young, Melissa A. Miller, Roman Kuchta, Jan Brabec, Seth D Newsome, Murray D DaileyAbstract:We present a novel case of an intestinal cestode infection in a southern sea otter (Enhydra lutris nereis). The cestode species Diphyllobothrium tetrapterum (syn. Diplogonoporus tetrapterus) was confirmed genetically. Stable isotope analysis of whiskers collected from the sea otter did not confirm the consumption of fish as the route of exposure.
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Serologic Detection of Subtype-specific Antibodies to Influenza A Viruses in Southern Sea Otters (Enhydra Lutris Nereis)
Journal of wildlife diseases, 2017Co-Authors: Alyssa M. Capuano, Melissa A. Miller, Erin Dodd, Francesca Batac, David E. Stallknecht, Megan E. Moriarty, Magdalena Plancarte, Walter M. BoyceAbstract:Abstract There are approximately 3,000 southern sea otters (Enhydra lutris nereis) in the nearshore environment along the California coast, US, and the species is classified as Threatened under the Endangered Species Act. We tested sera from 661 necropsied southern sea otters sampled from 1997 to 2015 to determine overall exposure to influenza A viruses (IAVs) and to identify subtype-specific antibody responses. Using an enzyme-linked immunosorbent assay (ELISA), antibodies to IAV nucleoproteins were detected in 160 (24.2%) otters, with seropositive animals found in every year except 2008. When the ELISA-positive samples were tested by virus microneutralization, antibody responses were detected to avian-origin hemagglutinin subtypes H1, H3, H4, H5, H6, H7, H9, and H11. Strong antibody responses to pandemic H1N1 (pdmH1N1) were also detected, indicating that epizootic transmission of pdmH1N1 occurred among the southern sea otter population after the emergence of this human-origin virus in 2009. We conclude ...
Nancy J Thomas - One of the best experts on this subject based on the ideXlab platform.
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Leptospirosis in Northern Sea Otters (Enhydra lutris kenyoni) from Washington, USA.
Journal of wildlife diseases, 2019Co-Authors: Susan Knowles, Deanna Lynch, Nancy J ThomasAbstract:We diagnosed leptospirosis in six northern sea otters (Enhydra lutris kenyoni) that stranded on beaches in Washington State, US in 2002. Significant gross findings included cyanotic oral mucous membranes, renal swelling, congestion or pale streaks on the cut surface of renal lobules, hematuria, dehydration, lymphadenopathy, pulmonary congestion, and rarely adrenal hemorrhage and congestion. Histopathology showed lymphoplasmacytic tubulointerstitial nephritis with intraluminal spirochetes and immunoreactivity to leptospiral antigens in the renal tubules and interstitium. A quantitative polymerase chain reaction (qPCR) using kidney or urine for the leptospiral lipL32 gene was positive with cycle threshold values indicative of abundant or moderate amounts of nucleic acid. A microscopic agglutination test showed the highest serum antibody titer to serovar Pomona and positive titers to serovars Autumnalis, Bratislava, Hebdomadis, Grippotyphosa, Icterohaemorrhagiae, Pyrogenes, Ballum, Canicola, and Hardjo. Although antibodies to Leptospira interrogans have been previously detected in sea otters, this report describes the pathology of leptospirosis in diseased free-ranging sea otters.
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MORTALITY TRENDS IN NORTHERN SEA OTTERS (Enhydra LUTRIS KENYONI) COLLECTED FROM THE COASTS OF WASHINGTON AND OREGON, USA (2002–15)
Journal of wildlife diseases, 2017Co-Authors: C. Leann White, Krysten L. Schuler, Deanna Lynch, Jitender P. Dubey, Susan Knowles, Emily W. Lankau, Valerie I. Shearn-bochsler, Marcos Isidoro-ayza, Nancy J ThomasAbstract:Abstract: During 2002−15 we examined the causes of mortality in a population of northern sea otters (Enhydra lutris kenyoni). Beachcast sea otters were collected primarily from the US coast of Washington. Although there are no permanent sea otter residents in Oregon, several beachcast otters were collected from the Oregon coast. Infectious diseases were the primary cause of death (56%) for otters we examined. Sarcocystosis was the leading infectious cause of death (54%) and was observed throughout the study period. Some infectious diseases, such as morbilliviral encephalitis and leptospirosis, were documented for a limited number of years and then not detected again despite continued testing for these pathogens in necropsied animals. Trauma was the second most common cause of death (14%) during the study period. The continued stable growth of the Washington population of otters suggests they are able to tolerate current mortality rates.
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sarcocystis neurona retinochoroiditis in a sea otter Enhydra lutris kenyoni
Veterinary Parasitology, 2011Co-Authors: J P Dubey, Nancy J ThomasAbstract:Sarcocystis neurona is an important cause of fatal disease in sea otters in the USA. Encephalitis is the predominant lesion and parasites are confined to the central nervous system and muscles. Here we report retinochoroiditis in a sea otter (Enhydra lutris kenyoni) found dead on Copalis Beach, WA, USA. Salient lesions were confined to the brain and eye. Multifocal nonsuppurative meningoencephalitis was present in the cerebrum and cerebellum associated with S. neurona schizonts. The retina of one eye had a focus of inflammation that contained numerous S. neurona schizonts and merozoites. The focus extended from the retinal pigment epithelium inward through all layers of the retina, but inflammation was most concentrated at the inner surface of the tapetum and the outer retina. The inner and outer nuclear layers of the retina were disorganized and irregular at the site of inflammation. There was severe congestion and mild hemorrhage in the choroid, and mild hemorrhage into the vitreous body. Immunohistochemistry with S. neurona-specific polyclonal rabbit antibodies stained schizonts and merozoites. To our knowledge this is the first report of S. neurona-associated retinochoroiditis in any naturally infected animal.
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toxoplasma gondii neospora caninum sarcocystis neurona and sarcocystis canis like infections in marine mammals
Veterinary Parasitology, 2003Co-Authors: J P Dubey, Nancy J Thomas, R Zarnke, S K Wong, W Van Bonn, M Briggs, J W Davis, R Ewing, M Mense, O C H KwokAbstract:Toxoplasma gondii, Neospora caninum, Sarcocystis neurona, and S. canis are related protozoans that can cause mortality in many species of domestic and wild animals. Recently, T. gondii and S. neurona were recognized to cause encephalitis in marine mammals. As yet, there is no report of natural exposure of N. caninum in marine mammals. In the present study, antibodies to T. gondii and N. caninum were assayed in sera of several species of marine mammals. For T. gondii, sera were diluted 1:25, 1:50, and 1:500 and assayed in the T. gondii modified agglutination test (MAT). Antibodies (MAT ≥1:25) to T. gondii were found in 89 of 115 (77%) dead, and 18 of 30 (60%) apparently healthy sea otters (Enhydra lutris), 51 of 311 (16%) Pacific harbor seals ( Phoca vitulina), 19 of 45 (42%) sea lions (Zalophus californianus), 5 of 32 (16%) ringed seals (Phoca hispida ), 4o f
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Sarcocysts of an Unidentified Species of Sarcocystis in the Sea Otter (Enhydra lutris)
The Journal of parasitology, 2003Co-Authors: Jitender P. Dubey, David S Lindsay, Benjamin M. Rosenthal, Nancy J ThomasAbstract:The number of Sarcocystis species that infect sea otters (Enhydra lutris) is unknown. Sea otter tissues were recently shown to harbor sarcocysts of S. neurona and of unidentified species of Sarcocystis. Whereas sarcocysts of S. neurona have walls 1–3 μm thick with type 9 villar protrusions, ultrastructure of a distinct thin-walled sarcocyst (0.5–0.7 μm thick) lacking villar protrusions, but instead exhibiting minute type 1 undulations on the sarcocyst wall, is described in this report. Parasites characterized from a sea otter infection were inferred to be related to, but distinct from, other species belonging to Sarcocystis, based on sequencing and phylogenetic analysis of a portion of the beta subunit of the plastid-encoded RNA polymerase gene.
Patricia A. Conrad - One of the best experts on this subject based on the ideXlab platform.
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Figure S1: Study location map. from Defining the risk landscape in the context of pathogen pollution: Toxoplasma gondii in sea otters along the Pacific Rim
2018Co-Authors: Tristan L. Burgess, James L. Bodkin, Michael J. Murray, Melissa A. Miller, Shawn Larson, Patricia A. Conrad, Tim M Tinker, Justin A Saarinen, Linda M. Nichol, Christine K. JohnsonAbstract:Map showing the location of all study regions for Northern sea otter (Enhydra lutris kenyoni). 1) Western Prince William Sound, Alaska; 2) Elfin Cove, Alaska; 3) Whale Bay, Alaska; 4) Nuchatlitz Inlet (Blue) and Clayoquot Sound (Green), British Columbia; 5) Olympic Peninsula, Washington. Coastal watersheds included in the study are outlined in black. See Figure 1 for Southern sea otter (E. lutris nereis) study regions in California
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Characterization of beta-hemolytic streptococci isolated from southern sea otters (Enhydra lutris nereis) stranded along the California coast.
Veterinary Microbiology, 2008Co-Authors: Denise M. Imai, Melissa A. Miller, Spencer S Jang, Patricia A. ConradAbstract:The goal of this study was to characterize the beta-hemolytic streptococci cultured from southern sea otters (Enhydra lutris nereis) stranded off the coast of California (USA) and to verify identifications made using the Lancefield system. Lancefield serotyping and biochemical analysis alone was inadequate for isolate characterization. Final identification was based on sequence analysis of a portion of the 16s ribosomal RNA gene from 12 of the 35 total isolates. The majority of isolates (10 of 12; 83.3%) were Streptococcus phocae and reacted with Lancefield group G and F antisera or were less frequently untypeable. The remaining isolates belonging to Lancefield group G were identified as S. dysgalactiae subsp. equisimilis (2 of 12; 16.7%). This is the first report of S. phocae in southern sea otters and further evidence of S. phocae expressing cell surface antigens compatible with Lancefield group G typing.
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transplacental toxoplasmosis in a wild southern sea otter Enhydra lutris nereis
Veterinary Parasitology, 2008Co-Authors: Patricia A. Conrad, Erick R James, Andrea E Packham, Sharon Toychoutka, Michael E GriggAbstract:In September 2004, a neonatal sea otter pup was found alive on the beach in northern Monterey Bay, CA. Efforts to locate the mother were unsuccessful. Due to a poor prognosis for successful rehabilitation, the pup was euthanized. Postmortem examination revealed emaciation, systemic lymphadenopathy and a malformation of the left cerebral temporal lobe. On histopathology, free tachyzoites and tissue cysts compatible with Toxoplasma gondii were observed in the brain, heart, thymus, liver, lymph nodes and peri-umbilical adipose. The presence of T. gondii within host tissues was associated with lymphoplasmacytic inflammation and tissue necrosis. Immunofluorescent antibody tests using postmortem serum were positive for anti-T. gondii IgM and IgG (at 1:320 and 1:1280 serum dilution, respectively), but were negative for IgG directed against Sarcocystis neurona and Neospora caninum (<1:40 each). Brain immunohistochemistry revealed positive staining for tachyzoites and tissue cysts using antiserum raised to T. gondii, but not S. neurona or N. caninum. T. gondii parasite DNA was obtained from extracts of brain and muscle by PCR amplification using the diagnostic B1 locus. Restriction enzyme digestion followed by gel electrophoresis and DNA sequencing confirmed the presence of Type X T. gondii, the strain identified in the majority of southern sea otter infections.