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31.
A single nucleotide polymorphism in the equine herpesvirus 1 (EHV-1) DNA polymerase gene (ORF30 A2254 to G) has been associated with clinical signs of equine herpes myeloencephalopathy (EHM). The purpose of our study was to determine the odds ratio for this genetic marker and EHM using a panel of field isolates from North America collected over the past twenty-three years. EHV-1 isolates cultured at the Cornell University Animal Health Diagnostic Laboratory from 1984 to 2007 were retrieved along with their clinical histories. DNA was extracted from these EHV-1 cultures and allelic discrimination was performed using real-time PCR. The results were confirmed by sequencing of the target region in ORF30. PCR and sequencing were in 100% agreement and showed that 19 out of the 176 isolates had the ORF30 G2254 allele (11%), of which16 were EHM cases and 3 respiratory or abortion cases. The odds of having neurologic disease with the ORF30 G2254 genotype were computed as 162 times greater than those with the opposite allele ORF30 A2254 (95% confidence interval: 35–742). Despite this strong statistical significance, 24% (5/21) of horses with neurologic disease in our study population harbored the “non-neurologic” form of the allele (ORF30 A2254), suggesting that other factors may also contribute to the onset of EHM.  相似文献   
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Background: Oxidative stress plays a role in the pathogenesis of many systemic diseases. Hospitalized human patients are glutathione, cysteine, and ascorbate deficient, and antioxidant depletion has been correlated with poor clinical outcome. To date little is known about antioxidant concentrations in hospitalized veterinary patients. The purpose of this study was to determine whether ascorbate, cysteine, or glutathione depletion is present in ill dogs and cats compared with healthy controls.
Hypothesis: Clinically ill dogs and cats would be antioxidant depleted, and depletion would correlate with illness severity and clinical outcome.
Animals: Clinically ill client-owned dogs (n = 61) and cats (n = 37), healthy control dogs (n = 37) and cats (n = 33).
Methods: Prospective, observational, case control study. Erythrocyte reduced glutathione, plasma cysteine, and plasma ascorbate were quantified using high-performance liquid chromatography.
Results: Clinically ill dogs had significantly lower erythrocyte glutathione concentrations (1.22 mM, range 0.55–3.61) compared with controls (1.91 mM, range 0.87–3.51; P = .0004), and glutathione depletion correlated with both illness severity ( P = .038) and mortality ( P = .010). Cats had higher ascorbate concentrations when ill (10.65 μM, range 1.13–25.26) compared with controls (3.68 μM, range 0.36–13.57; P = .0009).
Conclusions and Clinical Importance: Clinically ill dogs had decreased erythrocyte glutathione concentrations, which could be a marker of illness severity and prognostic of a poor outcome. Clinically ill cats had an unexpectedly high plasma ascorbate, which could represent a unique species response to oxidative stress.  相似文献   
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Water, Air, & Soil Pollution - Microbial fuel cells (MFCs) have gained increasing attention as an effective pathway for wastewater treatment and electrical energy recovery. In this study, the...  相似文献   
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Shade present in silvopasture systems could reduce heat stress associated with microclimatic conditions that characterize warm-weather portions of the year on the Coastal Plain of the Southeast USA. Objectives of this research were to: (1) quantify diurnal distribution patterns of landscape use and behavior of cattle in loblolly-pine (Pinus taeda) silvopasture versus open-pasture landscapes, and (2) relate observed differences in landscape use and cattle behavior patterns between the two pastures to differences in microclimatic conditions, and forage quantity and quality. The research was conducted in Chipley, Florida USA within a 5-ha cell of a loblolly-pine-bahiagrass (Paspalum notatum) silvopasture (tree age 20 year), and a 5-ha open bahiagrass pasture with unlimited access to an adjacent 1-ha wooded area. One-day observations of diurnal distribution and behavior of cattle were conducted in March, June, and September 2007; microclimatic conditions were measured, and forage quantity and quality were estimated within each landscape. Cattle utilized the landscape more evenly in the silvopasture versus the open-pasture and this difference was mainly attributed to reduced solar radiation recorded in the silvopasture. Grazing was the dominant behavior in the silvopasture while loafing was dominant in the open-pasture. Shade present in silvopasture appeared to reduce heat stress for cattle grazing during warm-weather portions of the year on the Coastal Plain of the Southeast USA. Further study is needed to determine how this reduction in heat stress influences cattle performance in southern-pine silvopasture, and the nature and extent of the interactions among animal distribution and behavior, microclimatic conditions, and forage characteristics in these systems.  相似文献   
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The backyard chicken (BYC) movement in the USA has increased human contact with poultry and subsequently, human contact with the pathogen Salmonella. However, to date, there have been few studies assessing prevalence of Salmonella in backyard flocks, despite the known public health risk this zoonotic bacterium poses. The objective of this study was to characterize human‐BYC interactions and assess the prevalence of Salmonella among BYC flocks. We interviewed 50 BYC owners using a structured questionnaire to determine flock and household characteristics that facilitate contact with BYC and that may be associated with Salmonella in the BYC environment. Composite faecal material, cloacal swabs and dust samples from 53 flocks housed on 50 residential properties in the Greater Boston, Massachusetts area were tested for Salmonella using standard culture techniques and confirmed using Matrix‐Assisted Laser Desorption/Ionization‐Time of Flight Mass Spectrometer. Microbroth dilution and whole genome sequencing were used to determine phenotypic and genotypic resistance profiles, respectively, and sequence results were used to determine multilocus sequencing type. No owners self‐reported a diagnosis of salmonellosis in the household. Over 75% of a subset of owners reported that they and their children consider BYC pets. This perception is evident in how owners reported interacting with their birds. Salmonella enterica subspecies enterica serotype Kentucky ST152 (serogroup C)—a strain not commonly associated with human infection—was confirmed in one flock, or 2% of tested flocks, and demonstrated resistance to tetracycline and streptomycin. We detected Salmonella at low prevalence in BYC. Further study of the health effects of exposure to zoonotic gastrointestinal pathogens such as Salmonella among families with BYC is warranted.  相似文献   
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This introduction situates key themesfound in papers given at a recent workshop on thechanging material practices, meanings, and regulationof US organic food production. The context is theemergence of an international bio-politics ofagriculture and food and, more particularly in the US,the contradictions of sustainable agriculturemovements catalyzed by the rapid scaling up of organicagriculture from a niche activity to nascentindustry.  相似文献   
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