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排序方式: 共有676条查询结果,搜索用时 15 毫秒
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The risk of salmonellae shedding by dogs fed Salmonella-contaminated commercial raw food diets 下载免费PDF全文
Finley R Ribble C Aramini J Vandermeer M Popa M Litman M Reid-Smith R 《The Canadian veterinary journal. La revue veterinaire canadienne》2007,48(1):69-75
Twenty-eight research dogs were enrolled to determine the prevalence of salmonellae shedding after consumption of 1 Salmonella-contaminated commercial raw food diet meal. Sixteen dogs were exposed to Salmonella-contaminated commercial raw food diets and 12 to Salmonella-free commercial raw food diets. Seven of the exposed dogs shed salmonellae 1-7 days after consumption of Salmonella-contaminated raw food diets. None of the dogs fed Salmonella-free diets shed salmonellae. No clinical signs were observed in either group. Five of the 7 dogs shed the same serotypes as those recovered from food samples used for feeding. Results showed the same serotypes and antimicrobial resistance pattern in 2 of the 7 shedders. Dogs fed Salmonella-contaminated raw food diets can shed salmonellae and may, therefore, be a source of environmental contamination potentially leading to human or animal illness. 相似文献
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Gonda KC Wilcke JR Crisman MV Ward DL Robertson JL Finco DR Braselton WE 《American journal of veterinary research》2003,64(12):1486-1490
OBJECTIVE: To determine whether pharmacokinetic analysis of data derived from a single i.v. dose of iohexol could be used to predict creatinine clearance and evaluate simplified methods for predicting serum clearance of iohexol with data derived from 2 or 3 blood samples in clinically normal foals. ANIMALS: 10 healthy foals. PROCEDURE: Serum disposition of iohexol and exogenous creatinine clearance was determined simultaneously in each foal (5 males and 5 females). A 3-compartment model of iohexol serum disposition was selected via standard methods. Iohexol clearance calculated from the model was compared with creatinine clearance. Separate limited-sample models were created with various combinations of sample times from the terminal slope of the plasma versus time profile for iohexol. Correction factors were determined for the limited-sample models, and iohexol clearance calculated via each method was compared with exogenous creatinine clearance by use of method comparison techniques. RESULTS: Mean exogenous creatinine clearance was 2.17 mL/min/kg. The disposition of iohexol was best described by a 3-compartment open model. Mean clearance value for iohexol was 2.15 mL/min/kg and was not significantly different from mean creatinine clearance. A method for predicting serum iohexol clearance based on a 2-sample protocol (3- and 4-hour samples) was developed. CONCLUSIONS AND CLINICAL RELEVANCE: Iohexol clearance can be used to predict exogenous creatinine clearance and can be determined from 2 blood samples taken after i.v. injection of iohexol. Appropriate correction factors for adult horses and horses with abnormal glomerular filtration rate need to be determined. 相似文献
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Athema L. Etzioni Rose E. Raskin William G. Van Alstine Jeff Yu 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2020,49(4):646-651
A 6-year-old, intact male, brindled, 30-Lb English Bulldog presented to the Purdue University Veterinary Teaching Hospital with a recurrent history of hematuria, periuria, and lethargy that responded temporarily to antibiotic therapy. The work-up included a complete blood count, serum biochemical profile, complete urinalysis, diagnostic imaging (abdominal radiographs and ultrasound with contrast urography), and exploratory laparotomy. The diagnostic imaging findings and subsequent exploratory revealed a unilateral, intraluminal, right-sided, 3-cm ureteral mass extending from the proximal ureter into the renal pelvis. Subsequently, a unilateral right-sided ureteronephrectomy followed by biopsy with cytopathology/cytology (impression smears) and histopathology of the ureteral mass was performed. The cytopathologic interpretation was benign mesenchymal proliferation with mildly atypical urothelial cells. The association of this mass with vascular tissue and a benign nuclear appearance on cytology is similar to reports of fibroepithelial polyps (FEPs) and myxomatous tumors. Histopathology diagnosed the mass as an FEP. Cytopathology proved useful in the presumptive diagnosis of this benign urothelial polyp. To the authors' knowledge, this is the first report using cytopathology to depict and characterize FEPs in veterinary and human medical literature. 相似文献
6.
Stephen J. Beatty Mark G. Allen Jeff M. Whitty Alan J. Lymbery James J. Keleher James R. Tweedley Brendan C. Ebner David L. Morgan 《Ecology of Freshwater Fish》2017,26(3):444-455
Goldfish (Carassius auratus) was one of the first fishes to be domesticated and has been widely introduced across the globe, but is now considered one of the world's worst invasive aquatic species. Surprisingly, there is a dearth of information on its spatial and temporal movement patterns, which hampers the development of effective control programmes. We examined the movement patterns of an introduced population of C. auratus in a south‐western Australian river using passive acoustic telemetry. The study population had a high residency index within the array (i.e. proportion of all days at liberty that, on average, each fish was detected by a receiver) with fish being detected on 64% of days. The individuals were also reasonably mobile, travelling a mean of 0.30 km (linear river kilometres).day‐1 within the array, and one fish moved 231.3 km over the 365‐day study period (including 5.4 km in a 24 hr period). Importantly, C. auratus displayed significant seasonal movement patterns including a clear shift in habitats during its breeding period with most mature individuals being detected in an off‐channel wetland during that time. The results of this study strongly suggest that C. auratus undertook a spawning migration into a lentic habitat. These results have important implications for developing control programmes for the species, such as targeting connections to off‐channel lentic systems during its breeding period. 相似文献
7.
Use of Canopy Temperature Measurements as a Screening Tool for Drought Tolerance in Spring Wheat 总被引:11,自引:0,他引:11
A. Rashid J. C. Stark A. Tanveer T. Mustafa 《Journal of Agronomy and Crop Science》1999,182(4):231-238
Remotely sensed infrared canopy temperatures provide an efficient method for rapid, non-destructive monitoring of whole-plant response to water stress. Field studies were conducted in 1992 and 1993 to evaluate the potential for using canopy temperatures to screen for drought tolerance in wheat. In both years, 12 spring wheat (Triticum aestivum L.) genotypes were grown under two irrigation levels (well-watered and moisture-stressed) imposed between tillering and anthesis with a line-source sprinkler irrigation system. Canopy temperature measurements were taken in well-watered and moisture-stressed plots between 1330 and 1430 h (MDT) on five clear days in 1992 and seven clear days in 1993 during the late vegetative and early reproductive growth periods following closure of the plant canopy. Genotypes exhibited differences in mean canopy temperatures across the two irrigation levels and two years. Klasic consistently had the highest canopy temperature under moisture-stressed conditions, while Bannock and Pondera had the lowest. Bannock, Yecora Rojo and Klasic had the warmest canopies under well-watered conditions, while Vandal, Amidon and Rick had the coolest. Plot-to-plot variation in canopy temperature under water stress conditions was evident for differences in grain yield. Significant correlations between canopy temperature and yield under moisture-stress conditions and drought susceptibility index values indicated the potential for screening wheat genotypes for drought response. 相似文献
8.
Mold JE Venkatasubrahmanyam S Burt TD Michaëlsson J Rivera JM Galkina SA Weinberg K Stoddart CA McCune JM 《Science (New York, N.Y.)》2010,330(6011):1695-1699
Although the mammalian immune system is generally thought to develop in a linear fashion, findings in avian and murine species argue instead for the developmentally ordered appearance (or "layering") of distinct hematopoietic stem cells (HSCs) that give rise to distinct lymphocyte lineages at different stages of development. Here we provide evidence of an analogous layered immune system in humans. Our results suggest that fetal and adult T cells are distinct populations that arise from different populations of HSCs that are present at different stages of development. We also provide evidence that the fetal T cell lineage is biased toward immune tolerance. These observations offer a mechanistic explanation for the tolerogenic properties of the developing fetus and for variable degrees of immune responsiveness at birth. 相似文献
9.
R. G. Novy J. L. Whitworth J. C. Stark B. A. Charlton S. Yilma N. R. Knowles M. J. Pavek R. R. Spear T. L. Brandt N. Olsen M. Thornton C. R. Brown 《American Journal of Potato Research》2014,91(4):380-393
Teton Russet is an early-maturing, medium-russeted, potato cultivar with high merit for both fresh-pack and processing. In early harvest trials in the Pacific Northwest, Teton Russet had total yields similar to Russet Norkotah, and higher than Ranger Russet and Russet Burbank. Marketable yield of Teton Russet in the early harvest trials was also comparable to or higher than Russet Norkotah in Washington and Oregon, and higher than Ranger Russet and Russet Burbank at these sites, as well as in Idaho. In full-season trials, while total yield of the earlier-maturing Teton Russet tended to be lower than Ranger Russet and Russet Burbank, marketable yield was generally higher than Russet Burbank across the majority of sites due to its higher percentage of U.S. No. 1 tubers. Teton Russet is suitable for processing, with acceptable fry color following up to 8 months of storage at 8.9 °C. Uniformity of fry color was also very consistent. Teton Russet has shown lower levels of the amino acid asparagine relative to Ranger Russet and Russet Burbank which may contribute to lower acrylamide levels in French fries and other processed potato products. Teton Russet is notable for having resistance to common scab (Streptomyces spp.) and Fusarium dry rot, and is moderately resistant to tuber net necrosis. Analyses have also shown Teton Russet to have significantly higher protein levels than Russet Norkotah, Ranger Russet, and Russet Burbank, as well as higher vitamin C content than Russet Norkotah and Russet Burbank. Teton Russet was released in 2011 by the USDA-ARS and the Agricultural Experiment Stations of Idaho, Oregon, and Washington, and is a product of the Pacific Northwest Potato Variety (Tri-State) Development Program. 相似文献
10.
Jeff Rutan 《Journal of Crop Improvement》2017,31(6):780-800
Weather uncertainty and soil spatial variability impact nitrogen (N) cycling and corn (Zea mays L.) growth, making accurate N predictions a challenge. Field studies were conducted in Lansing, Michigan, to evaluate a computer model (i.e., Adapt-N), a preseason year-based model (i.e., maximum return to N [MRTN]), and a crop sensor model (i.e., active canopy sensor with algorithm) for recommending corn N rates. To determine site-specific economic optimum N rates (EONR), five N rates were also applied (0, 33%, 66%, 133%, and 166% of the suggested MRTN) as starter + sidedress (SD) at V4. In a wet year (i.e., 2015), Adapt-N increased V8 SD N rates 35 kg N ha?1 relative to the MRTN V4 SD N application. Although the greater rate of N may have provided additional yield protection, no statistical yield differences were observed between the two models. The MRTN model increased partial factor productivity (PFP) 20% relative to Adapt-N. Limited expression of V8 corn N deficiency reduced crop sensor total N rates (21–56 kg N ha?1) and yield (0.82–1.05 Mg ha?1) relative to other models. In a drier year (i.e., 2016), N demand was reduced (EONR 64 kg N ha?1 less than 2015), resulting in similar corn response to all three models. Despite differences in actual corn N rate recommendations, all three models resulted in similar economic net returns across study years.Abbreviations: EONR, economic optimum nitrogen rate; MRTN, Maximum Return to Nitrogen; NUE, nitrogen-use efficiency; PFP, partial factor productivity; SBNRC, sensor-based nitrogen rate calculator; SD, side-dress 相似文献