an ecologic study comparing distribution of pasteurella trehalosi and mannheimia haemolytica between sierra nevada bighorn sheep, white mountain bighorn sheep, and domestic sheep.the prevalence and phenotypic variability of pasteurella and mannheimia isolates from sierra nevada bighorn sheep (ovis canadensis sierrae), white mountain bighorn sheep (ovis canadensis nelsoni), and domestic sheep (ovis aries) from california, usa, were compared. the white mountain bighorn sheep population had a recent history of pneumonia-associated mortality, whereas the sierra nevada bighorn sheep population had no recent history of pneumonia-associated mortality. the domestic sheep flocks ...200919901369
comparative molecular characterization of corynebacterium pseudotuberculosis of different origin.ribotyping and susceptibility to 17 antimicrobial agents were used to compare 37 isolates of corynebacterium pseudotuberculosis (28 from horses, 1 from cattle, 3 from sheep and 5 from goats) derived from various types of lesions, and different geographic locations. according to the presence of nitrate reductase, all but one isolate from horses reduced nitrate (nitrate-positive), whereas all isolates from sheep and goats were unable to reduce nitrate (nitrate-negative). the ribotype of the nitrat ...19989695286
pleistocene to historic shifts in bald eagle diets on the channel islands, california.studies of current interactions among species, their prey, and environmental factors are essential for mitigating immediate threats to population viability, but the true range of behavioral and ecological flexibility can be determined only through research on deeper timescales. ecological data spanning centuries to millennia provide important contextual information for long-term management strategies, especially for species that now are living in relict populations. here we use a variety of meth ...201020439737
population-specific vital rate contributions influence management of an endangered develop effective management strategies for the recovery of threatened and endangered species, it is critical to identify those vital rates (survival and reproductive parameters) responsible for poor population performance and those whose increase will most efficiently change a population's trajectory. in actual application, however, approaches identifying key vital rates are often limited by inadequate demographic data, by unrealistic assumptions of asymptotic population dynamics, and of equ ...201020945773
isolation and in vitro cultivation of babesia parasites from free-ranging desert bighorn sheep (ovis canadensis nelsoni) and mule deer (odocoileus hemionus) in california.protozoal parasites of the genus babesia were isolated for the first time from free-ranging desert bighorn sheep (ovis canadensis nelsoni) and mule deer (odocoileus hemionus) populations in california by in vitro culture of host blood. these naturally infected animals did not have microscopically detectable parasitemia at the time blood was collected for parasite cultivation. three isolates of small babesia parasites were cultured from different sample groups of bighorn sheep, and 2 isolates of ...19938437062
prevalence and molecular characterization of escherichia coli o157:h7 by multiple-locus variable-number tandem repeat analysis and pulsed-field gel electrophoresis in three sheep farming operations in california.a year-long study was conducted to determine the fecal prevalence of escherichia coli o157:h7 in three sheep ranches. strain diversity and persistence were compared with multiple-locus variable-number tandem repeat analysis and pulsed-field gel electrophoresis. ranch c, a feedlot, consisted of young sheep raised predominantly on a high-grain diet. the other two sites consisted of sheep raised on native pasture and a combination of native and irrigated pasture. forty fecal samples were collected ...201121902909
hierarchical distance-sampling models to estimate population size and habitat-specific abundance of an island endemic.population size and habitat-specific abundance estimates are essential for conservation management. a major impediment to obtaining such estimates is that few statistical models are able to simultaneously account for both spatial variation in abundance and heterogeneity in detection probability, and still be amenable to large-scale applications. the hierarchical distance-sampling model of j. a. royle, d. k. dawson, and s. bates provides a practical solution. here, we extend this model to estimat ...201223210315
prevalence of antibodies of selected infectious disease agents in the peninsular desert bighorn sheep (ovis canadensis cremnobates) of the santa rosa mountains, california. 19826285010
analysis of the genomes of bluetongue viruses recovered from different states of the united states and at different times.the ribonucleic acid (rna) genomes of the original representatives of the four serotypes of bluetongue virus (btv) isolated from the united states (btv-10, btv-11, btv-13 and btv-17) have been analyzed by polyacrylamide gel electrophoresis. ten double-stranded rna species were resolved for each virus and categorized into the size classes of large (l segments #1-3), medium (m segments #4-6) and small (s segments #7-10). minor electrophoretic mobility differences were observed for the m5 and s10 r ...19826278927
farm and animal exposures and pediatric brain tumors: results from the united states west coast childhood brain tumor study.nineteen counties from san francisco and los angeles, california and seattle, washington were the united states sites for a large population-based case-control study of childhood brain tumors (cbts), sponsored by the national cancer institute. cbt patients who were < 20 years of age and were diagnosed between 1984 and 1991 were reported to each region's cancer registry. the 801 control subjects were obtained by random digit dial and were frequency-matched to the 540 cbt patients in san francisco ...19989752988
reference intervals for mineral concentrations in whole blood and serum of bighorn sheep (ovis canadensis) in california.whole blood and serum mineral concentrations were measured in diverse bighorn sheep (ovis canadensis) metapopulations in california, and 90% reference intervals were determined. while there were some statistical differences between median concentrations among the different metapopulations, detected values were generally in good agreement with concentrations reported for other bighorn sheep populations and with reference ranges widely accepted for domestic sheep (ovis aries). although median whol ...201222529120
meat preparation and colorectal adenomas in a large sigmoidoscopy-based case-control study in california (united states).the often observed association between red meat and colorectal cancer could be due in part to mutagens, such as heterocyclic amines (hca), that are present in cooked meat. hcas are highly mutagenic and cause intestinal tumors in animals. the hypothesis that hcas are also carcinogenic to humans remains to be substantiated in epidemiologic studies. we determined the associations of meat preparation and frequency of intake (proxy variables for hca exposure, since hca concentration depends on the ty ...19979134241
bluetongue disease and the molecular epidemiology of viruses from the western united states.prototype and field isolates of united states bluetongue viruses were evaluated for genetic heterogeneity by sequence analyses. prototype viruses btv 2, 10, 11, 13 and 17 from the united states, btv 10 vaccine virus, and field isolates of btv 10 and 17 from california were analyzed. gene segment 2 from btv 10 and 17 isolated in 1980-81 and 1990 was sequenced along with gene segment 9 from btv 10 isolates. the wisconsin package was used to analyze nucleotide sequences and to predict amino acid co ...19968800543
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