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101.
Nolen-Walston RD D'Oench SM Hanelt LM Sharkey LC Paradis MR 《Journal of the American Veterinary Medical Association》2004,224(12):1964-6, 1931
An 11-year-old Hanoverian-cross gelding was evaluated because of acute onset of ataxia, recumbency, and fever. At the stable, this and other horses had recently been infested with ticks. Results of analysis of a sample of CSF were within reference limits, but hematologic abnormalities included lymphopenia, thrombocytopenia, mild anemia, and intracytoplasmic inclusion bodies in neutrophils that were consistent with Anaplasma phagocytophilum (previously Ehrlichia equi). Results of serum biochemical analyses were characteristic of infection and included high, unconjugated bilirubin concentration. Other common causes of recumbency in horses, such as equine protozoal myeloencephalitis, infection with eastern or western equine encephalitis viruses and equine herpesvirus-1, West Nile viral encephalitis, trauma, and metabolic disease, were ruled out. The horse responded quickly to i.v. administration of oxytetracycline and recovered fully within 6 days. 相似文献
102.
Martin LG Groman RP Fletcher DJ Behrend EN Kemppainen RJ Moser VR Hickey KC 《Journal of the American Veterinary Medical Association》2008,233(1):87-95
OBJECTIVE: To evaluate pituitary-adrenal function in critically ill dogs with sepsis, severe trauma, and gastric dilatation-volvulus (GDV). DESIGN: Cohort study. ANIMALS: 31 ill dogs admitted to an intensive care unit (ICU) at Washington State University or the University of Pennsylvania; all dogs had acute critical illness for < 48 hours prior to admission. PROCEDURES: Baseline and ACTH-stimulated serum cortisol concentrations and baseline plasma ACTH concentrations were assayed for each dog within 24 hours after admission to the ICU. The change in cortisol concentrations (Delta-cortisol) was calculated for each dog. Morbidity and mortality data were recorded for each patient. RESULTS: Overall, 17 of 31 (55%) acutely critically ill dogs had at least 1 biochemical abnormality suggestive of adrenal gland or pituitary gland insufficiency. Only 1 (3%) dog had an exaggerated response to ACTH stimulation. Dogs with Delta-cortisol < or = 83 nmol/L were 5.7 times as likely to be receiving vasopressors as were dogs with Delta-cortisol > 83 nmol/L. No differences were detected among dogs with sepsis, severe trauma, or GDV with respect to mean baseline and ACTH-stimulated serum cortisol concentrations, Delta-cortisol, and baseline plasma ACTH concentrations. CONCLUSIONS AND CLINICAL RELEVANCE: Biochemical abnormalities of the hypothalamic-pituitary-adrenal axis indicative of adrenal gland or pituitary gland insufficiency were common in critically ill dogs, whereas exaggerated responses to ACTH administration were uncommon. Acutely ill dogs with Delta-cortisol < or = 83 nmol/L may be more likely to require vasopressors as part of the treatment plan. 相似文献
103.
Background
Identification of Staphylococci to species level in veterinary microbiology is important to inform therapeutic intervention and management. We report on the efficacy of three routinely used commercial phenotypic methods for staphylococcal species identification, namely API Staph 32 (bioMérieux), RapID (Remel) and Staph-Zym (Rosco Diagnostica) compared to genotyping as a reference method to identify 52 staphylococcal clinical isolates (23 coagulase positive; 29 coagulase negative) from companion animals in Irish veterinary hospitals.Results
Genotyping of a 412 bp fragment of the staphylococcal tuf gene and coagulase testing were carried out on all 52 veterinary samples along with 7 reference strains. In addition, genotyping of the staphylococcal rpoB gene, as well as PCR-RFLP of the pta gene, were performed to definitively identify members of the Staphylococcus intermedius group (SIG). The API Staph 32 correctly identified all S. aureus isolates (11/11), 83% (10/12) of the SIG species, and 66% (19/29) of the coagulase negative species. RapID and Staph-Zym correctly identified 61% (14/23) and 0% (0/23) respectively of the coagulase-positives, and 10% (3/29) and 3% (1/29) respectively of the coagulase-negative species.Conclusions
Commercially available phenotypic species identification tests are inadequate for the correct identification of both coagulase negative and coagulase positive staphylococcal species from companion animals. Genotyping using the tuf gene sequence is superior to phenotyping for identification of staphylococcal species of animal origin. However, use of PCR-RFLP of pta gene or rpoB sequencing is recommended as a confirmatory method for discriminating between SIG isolates. 相似文献104.
105.
Labruna MB McBride JW Camargo LM Aguiar DM Yabsley MJ Davidson WR Stromdahl EY Williamson PC Stich RW Long SW Camargo EP Walker DH 《Veterinary parasitology》2007,143(2):189-195
A molecular epidemiologic investigation in two Brazilian states (Rondônia and São Paulo) was undertaken to determine if Ehrlichia species responsible for human and animal ehrlichioses in North America could be found in Brazilian vectors, potential natural mammalian reservoirs and febrile human patients with a tick bite history. Samples, including 376 ticks comprising 9 Amblyomma species, 29 capybara (Hydrochaeris hydrochaeris) spleens, 5 canine blood, and 75 human blood samples from febrile patients with history of tick bites were tested by a real-time PCR assay targeting a fragment of the Ehrlichia dsb gene. Ehrlichia DNA was not detected in any tick, capybara or human samples. In contrast, 4 out of 5 dogs contained Ehrlichia canis DNA in their blood, which were sequenced, representing the first report of E. canis infecting dogs in the Amazon region of Brazil. Further studies are needed to evaluate the presence of other agents of human and animal ehrlichioses in Brazil. 相似文献
106.
Corbin D. Hilling Yan Jiao Mary C. Fabrizio Paul L. Angermeier Aaron J. Bunch Donald J. Orth 《Fisheries Management and Ecology》2023,30(1):70-88
Stock assessment modeling provides a means to estimate the population dynamics of invasive fishes and may do so despite data limitations. Blue catfish (Ictalurus furcatus) were introduced to the Chesapeake Bay watershed to support recreational fisheries but also consume species of conservation need and economic importance. To assess management tradeoffs, managers need to understand the current status of the population and anticipate future population abundance and trends. A Bayesian size-based stock assessment model was used to estimate blue catfish abundance, fishing mortality, and size structure over time (2001–2016) in the tidal James River. The model estimated population size increases until around 2006, with declines in total abundance after 2011 and large blue catfish (≥80 cm total length) after 2001. These first estimates of blue catfish population dynamics in the Chesapeake Bay region provide inputs for projection models to evaluate prospective management actions and identify monitoring needs. 相似文献
107.
The riverscape perspective recognizes the heterogeneous habitat types within the stream corridor as a single, integrated ecological
unit operating across spatial scales. Although there is ample evidence that the riverscape notion is appropriate in understanding
the physical phenomena of stream corridors, significantly less attention has focused on its ecological ramifications. To this
end, we surveyed riverscape habitat variables and bird community characteristics in the Champlain Valley of Vermont, USA.
From the data collected, we used information theoretic methodology (AICc) to model relationships between bird community attributes and key habitat variables across the riverscape. Our models with
the greatest support suggest that riverine bird communities respond to a suite of characteristics; representing a variety
of riverscape habitats at the in-stream, floodplain, and riparian levels. Channel slope, drainage area, percent conifers,
and in-stream habitat condition were among the most influential variables. We found that piscivores are potentially important
indicators of riverscape condition, responding to a host of variables across the riverscape. Our results endorse a holistic
approach to assessing and managing the mosaic of patches in the riverscape and suggest that a riverscape approach has significant
conservation potential. 相似文献
108.
The rates of sap flow and xylem vessel features were studied in two-year-old nongrafted and grafted avocado (Persea americana Mill.) trees. Daily sap flow rates were measured with heat and balance stem gauges in clonal Duke 7 (D7) and Toro Canyon (TC) trees and ‘Hass’ clonal scions grafted onto clonal D7 (H/D7) and TC (H/TC) rootstocks. Vessel features as size, number and total vessel area were determined histologically in the stem of the scion and rootstock and the roots of the grafted trees. Significant differences in the sap flow rate were found among the rootstocks, where D7 had a 29% higher sap flow rate than did TC (grafted and nongrafted trees). There were no differences among xylem vessel features in the stems of any of the varieties. However in the roots, D7 had wider and fewer vessels then TC do. Also, D7 had a 19% higher total vessel area than TC. These results suggest that the differences in water consumption of ‘Hass’ on different rootstocks may be associated with differences in the efficiency of the roots to absorb water across conductive tissue which may be linked to differences in the area of xylem vessels in the root. 相似文献
109.
Ground-layer vegetation was sampled along selected trail corridors to determine whether corridors provide habitat for certain species and act as conduits for species movement. Patterns of plant species composition were analyzed in relation to distance from trail edge, level of trail use, and distance from trailheads, junctions, and campgrounds. Species composition was significantly affected by distance from trail edge and level of trail use, as species were favored or inhibited by the corridor, depending upon their growth habits. Species composition was also affected by distance from trailheads. These findings, along with the presence of exotic species, indicate that trail corridors in Rocky Mountain National Park function as habitat and conduits for movement of plant species. 相似文献
110.
Soil microbial processes and Testacea (Protozoa) as indicators of heavy metal pollution The influence of the emissions from a copper smelter on soil microbial processes was investigated at 4 meadow sites along a concentration gradient in Brixlegg (Austria). The first site is within 300 m of the source, further sites are situated 1125 m, 2425 m and 5900 m from the smelter. Heavy metal pollution close to the smelter induced a decrease of microbial biomass, respiration, dehydrogenase activity and the related enzyme activities in soil samples (5–10 cm soil depth): Protease, alkaline phosphatase, arylsulfatase, actual and potential nitrification. Thus, soil microbial processes in the 5–10 cm layer appear to be directly affected by heavy metals. Regarding the testate amoebae, their low individual and species numbers at 5–10 cm soil depth obstruct clear trends of this animal group. However, comparing the heavy polluted site with the control area, abundances, species numbers and biomass of testate amoebae slightly decreased at the polluted site (5–10 cm). Contrary to the results in the 5–10 cm layer, most soil microbial processes as well as abundances, species numbers and biomass of testaceans in the upper soil (0–5 cm) seem to be more strongly influenced by the supply of organic substrate than by the content of heavy metals in the soil. 相似文献