64 research outputs found
Patterns of genomic sequence diversity among their simian immunodeficiency viruses suggest that L'Hoest monkeys (Cercopithecus lhoesti) are a natural lentivirus reservoir
SIVagm Infection in Wild African Green Monkeys from South Africa: Epidemiology, Natural History, and Evolutionary Considerations
Pathogenesis studies of SIV infection have not been performed to date in wild monkeys due to difficulty in collecting and storing samples on site and the lack of analytical reagents covering the extensive SIV diversity. We performed a large scale study of molecular epidemiology and natural history of SIVagm infection in 225 free-ranging AGMs from multiple locations in South Africa. SIV prevalence (established by sequencing pol, env, and gag) varied dramatically between infant/juvenile (7%) and adult animals (68%) (p<0.0001), and between adult females (78%) and males (57%). Phylogenetic analyses revealed an extensive genetic diversity, including frequent recombination events. Some AGMs harbored epidemiologically linked viruses. Viruses infecting AGMs in the Free State, which are separated from those on the coastal side by the Drakensberg Mountains, formed a separate cluster in the phylogenetic trees; this observation supports a long standing presence of SIV in AGMs, at least from the time of their speciation to their Plio-Pleistocene migration. Specific primers/probes were synthesized based on the pol sequence data and viral loads (VLs) were quantified. VLs were of 104-106 RNA copies/ml, in the range of those observed in experimentally-infected monkeys, validating the experimental approaches in natural hosts. VLs were significantly higher (107-108 RNA copies/ml) in 10 AGMs diagnosed as acutely infected based on SIV seronegativity (Fiebig II), which suggests a very active transmission of SIVagm in the wild. Neither cytokine levels (as biomarkers of immune activation) nor sCD14 levels (a biomarker of microbial translocation) were different between SIV-infected and SIV-uninfected monkeys. This complex algorithm combining sequencing and phylogeny, VL quantification, serology, and testing of surrogate markers of microbial translocation and immune activation permits a systematic investigation of the epidemiology, viral diversity and natural history of SIV infection in wild African natural hosts. Β© 2013 Ma et al
Morbidity and mortality in free-living raptorial birds of Northern California: a retrospective study, 1983-1994
abstract: The causes of morbidity and mortality in 17 free-living raptorial bird species of northern California between 1983 and 1994 were studied. Of 409 birds examined at the Veterinary Medical Teaching Hospital, University of California, USA, 58% died of traumatic injuries and 30% died of infectious disease. The most frequently observed infectious diseases were: aspergillosis (25%), avian pox (17.7%), colibacillosis (10.5%), staphylococcosis (8.9%) and avian cholera (7.3%). The most frequent presenting signs were fractures, recumbency, shock, suboptimal weight and dehydration. 30% of these raptors were in good nutritional condition, whereas nearly 50% were in fair condition or were emaciated. Pathological lesions found in a few raptors (0.8%) indicated that an underlying disease (e.g. tuberculosis) was present before the birds succumbed to an acute, lethal, traumatic incident
Evaluation of changes in hematologic and clinical biochemical values after exposure to petroleum products in mink (Mustela vison) as a model for assessment of sea otters (Enhydra lutris)
abstract: The effects of petroleum exposure on haematological and clinical biochemical results of mink were identified and variables that may be useful for making management decisions involving sea otters (Enhydra lutris) that have been exposed to oil in their environment were identified [California, USA; date not given]. 122 American mink (Mustela vison) were used in the study. Mink were exposed once to a slick of oil (Alaskan North Slope crude oil or bunker C fuel oil) on seawater or via low-level contamination of their daily rations. In the acute phase of exposure, petroleum directly affected RBC, WBC, neutrophil, and lymphocyte counts, fibrinogen, sodium, calcium, creatinine, total protein, and cholesterol concentrations, and alanine transaminase, creatine kinase, alkaline phosphatase, and Ξ³-glutamyltransferase activities. Aspartate transaminase, alkaline phosphatase, Ξ³-glutamyltransferase, and lactate dehydrogenase activities and cholesterol concentration also varied as a result of chronic low-level contamination of feed. Our results are in agreement with reports that attribute increased alanine transaminase and alkaline phosphatase activities and decreased total protein concentration to petroleum exposure in sea otters during an oil spill. Sodium, calcium, creatinine, cholesterol, and lactate dehydrogenase may be valuable variables to assess for guidance during initial treatment of sea otters exposed to oil spills as well as for predicting which petroleum-exposed sea otters will reproduce following an oil spill. Measurement of these variables should aid wildlife professionals in making decisions regarding treatment of sea otters after oil spills
Changes in blubber contaminant concentrations in California sea lions (<em>Zalophus californianus</em>) associated with weight loss and gain during rehabilitation
California sea lions have high levels of persistent organic pollutants (POPs) in their blubber. Animals affected by domoic acid fast and refeed during their rehabilitation. We studied the effect of decreases in total body mass (16 7% of initial body mass) on blubber POP contaminant concentrations and estimated POP burdens during fasting (12 5 days) in 19 California sea lions. The effect of refeeding (92 8% of initial body mass) was also investigated. Significant increases in the concentration of all POPs were found over the mass loss period and decreases during mass gain. A basic mass balance model indicated that the changes did not conform to a simple concentrating and diluting pattern and a proportion of the contaminants were lost from the lipid pool. During mass loss, the lower chlorinated polychlorinated biphenyl congeners, chlordanes, and hexachlorocyclohexanes were lost at a higher rate than the other contaminant classes (particularly polybrominated diphenyl ethers). During mass gain the behavior of all contaminant classes was more consistent with the dilution model. These results indicate the importance of considering the energetic context when sampling blubber for long-term contaminant monitoring and suggest an initial approach to adjust for such differences
Changes in blubber contaminant concentrations in California sea lions (<em>Zalophus californianus</em>) associated with weight loss and gain during rehabilitation
California sea lions have high levels of persistent organic pollutants (POPs) in their blubber. Animals affected by domoic acid fast and refeed during their rehabilitation. We studied the effect of decreases in total body mass (16 7% of initial body mass) on blubber POP contaminant concentrations and estimated POP burdens during fasting (12 5 days) in 19 California sea lions. The effect of refeeding (92 8% of initial body mass) was also investigated. Significant increases in the concentration of all POPs were found over the mass loss period and decreases during mass gain. A basic mass balance model indicated that the changes did not conform to a simple concentrating and diluting pattern and a proportion of the contaminants were lost from the lipid pool. During mass loss, the lower chlorinated polychlorinated biphenyl congeners, chlordanes, and hexachlorocyclohexanes were lost at a higher rate than the other contaminant classes (particularly polybrominated diphenyl ethers). During mass gain the behavior of all contaminant classes was more consistent with the dilution model. These results indicate the importance of considering the energetic context when sampling blubber for long-term contaminant monitoring and suggest an initial approach to adjust for such differences
Changes in Blubber Contaminant Concentrations in California Sea Lions (Zalophus californianus) associated with Weight Loss and Gain during Rehabilitation
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