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471.
Evaluation of a Whole Blood Glutaraldehyde Coagulation Test for the Detection of Failure of Passive Transfer in Calves 总被引:1,自引:1,他引:0
Jeff W. Tyler Thomas E. Besser Leilani Wilson Dale D. Hancock Sean Sanders Douglas E. Rea 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1996,10(2):82-84
The accuracy of a commercially available whole blood glutaraldehyde clot test in the detection of failure of passive transfer (serum immunoglobulin [Ig]G1 < 1,000 mg/dL) in neonatal calves was evaluated. Serum samples were obtained from 242 calves ranging in age from 1 to 8 days, and comparisons were made with serum lgG1 concentrations determined by radial immunodiffusion. Both the sensitivity and specificity of the currently marketed whole blood glutaraldehyde clot test are inadequate for routine diagnostic use. Concerns regarding test sensitivity are the most problematic. Sensitivity varied from 0.41 to 0.00, depending on the choice of test endpoint. Specificity varied from 0.85 to 1.00, depending on the choice of test endpoint. Regression analysis demonstrated that the relationship between serum lgG1 concentration and the glutaraldehyde clot results, although significant (P< .10), was of negligible biological relevance ( r 2 = .034). J Vet Intern Med 1996; 10:82–84. Copyright © 1996 by the American College of Veterinary Internal Medicine . 相似文献
472.
David Francoz Jean-Martin Lapointe Vincent Wellemans André Desrochers Jeff L Caswell Jeff L Stott Pascal Dubreuil 《Journal of veterinary diagnostic investigation》2004,16(5):432-435
A 6-month-old Holstein heifer that was nonresponsive to medical treatment was evaluated for chronic respiratory disease. Complete blood count and serum chemistry revealed neutrophilic leukocytosis and low globulin levels. Assays for bovine leukemia virus, bovine virus diarrhea, and bovine leukocyte adhesion deficiency were negative. Serum globulin subclass assays revealed transient low concentrations of immunoglobulin (Ig) G1 and IgA, persistent low IgG2, and subnormal IgM. Vaccination with 2 doses of multiple, inactived viruses induced seroconversion for most viruses. Flow cytometric analysis of blood lymphocyte subpopulation demonstrated an increase in CD5+ B-cells. Blood lymphocyte proliferation and neutrophil function tests were normal. Results of immunologic assays indicated IgG2 deficiency with transient hypogammaglobulinemia. 相似文献
473.
474.
Wm Kirk Suedmeyer Chris Ludlow Candace Layton Jeff Dennis Margaret Miller 《Journal of zoo and wildlife medicine》2004,35(4):572-575
A 3-yr-old intact male dingo (Canis familiaris dingo) presented with a 3-mo history of diarrhea. The diarrhea did not resolve with antibiotics or intestinal protectants. Fecal examination for parasites, fecal cultures, physical examination, and radiographs were unremarkable. Enteroscopic duodenal biopsies showed dilated lacteals without inflammation. Results of serum folate, cobalamin, and trypsin-like immunoreactivity were normal. Low serum total protein and albumin combined with increased fecal levels of alpha-1 protease inhibitor suggested the diagnosis of lymphangiectasia. Full-thickness intestinal biopsies of the duodenum, jejunum, and ileum revealed dilated mucosal and submucosal lacteals without associated inflammation, confirming the diagnosis of primary lymphangiectasia. Currently, the dingo is being maintained with nutritional management. 相似文献
475.
Dong Taifeng Shang Jiali Liu Jiangui Qian Budong Jing Qi Ma Baoluo Huffman Ted Geng Xiaoyuan Sow Abdoul Shi Yichao Canisius Francis Jiao Xianfeng Kovacs John M. Walters Dan Cable Jeff Wilson Jeff 《Precision Agriculture》2019,20(6):1231-1250
Precision Agriculture - Remote sensing has been recognized as a cost-effective way to detect the spatial and temporal variability of crop growth and productivity. In this study, multispectral... 相似文献
476.
Julian J. Smith Jeff Waage James W. Woodhall Sam J. Bishop Nicola J. Spence 《European journal of plant pathology / European Foundation for Plant Pathology》2008,121(3):365-375
The consequences of a globalisation of trade and climate change present an increased threat from first-entry pests and a challenge
to plant health authorities. In this paper, pest reporting for the continents of Africa and Europe are discussed, and argued
as a barometer of effective Plant Pest Diagnostic Services (PPDS) in terms of human capacity, infrastructure and policy-culture
for phytosanitary issues. To illustrate particular areas of concern, case studies are presented on recent pest events which
include outbreaks of Ralstonia solanacearum on Pelargonium, Xanthomonas campestris pv. musacearum on banana (banana Xanthomonas wilt) and Puccinia graminis f.sp. tritici race Ug99 on wheat (black stem rust). Examples are given of some recent initiatives to invigorate diagnostic capacity in
East Africa, spanning state-of-the-art centres of excellence, traditional capacity building and networking projects, and grass-root
level 'going-public' pest surveillance initiatives. Discussion is presented on the provision of PPDS and the impact of technology,
institutional factors, the private sector, accreditation of services and policy. Emphasis is placed on the role of PPDS in
support of regulatory policy. In recognising the precarious nature of many African cropping systems, the argument is made
for a more consolidated approach to PPDS in and for Africa. The paper is presented from the perspective of European practitioners
in pest diagnostic and risk analysis. 相似文献
477.
This work presents the results from the initial model development of a simulator to predict vegetation dynamics in young plantations
growing in a Mediterranean environment. The simulator can predict growth dynamics for coniferous crop trees as well as competing
hardwoods and shrubs. Model specification included conifer, shrub, and hardwood competition expressed at the plot-level. The
system employs water-holding capacity as an indicator of productivity. Growth data were obtained from 109 plantations, ranging
in age from 3 to 25, in southern Oregon and northern California. Douglas-fir (Pseudotsuga menziesii Mirb. Franco), the most common conifer species, was observed in 80 of the sampled stands. These observations were used for
model development of the primary driving functions, which forecast 2-year basal diameter increment, height increment, and
crown width increment.
Parameters for all three dynamic expressions for growth were estimated using weighted, nonlinear three-stage least squares.
This estimation method provided a predictive model with slight improvements in standard errors for two of the three equations
(an average of 3% for height and diameter growth) and no improvement for crown width, when compared with two-stage least squares.
The system includes competition from shrubs and hardwoods in predictions of height growth, diameter growth and crown width
increment. This allows individual-tree/distance-independent simulator architecture to be extended to young plantations in
southern Oregon and northern California. 相似文献
478.
Andrew J. Kroll Ken Risenhoover Tim McBride Eric Beach Brian J. Kernohan Jeff Light Janette Bach 《Forest Ecology and Management》2008,255(11):3726-3735
Potential immediate and prolonged impact of timber harvests on stream-associated amphibians (SAA; torrent (Rhyacotriton spp.) and giant salamanders (Dicamptodon spp.) and coastal tailed frogs (Ascaphus truei)) in Oregon and Washington, USA is a management concern, in part because of widespread commercial management of forests across their geographic distributions. Relationships between SAA occupancy and detection probabilities, environmental variables, and management effects were examined in 141 randomly selected perennial streams in commercial forests west of the Cascade Crest in Oregon and Washington from July to October, 2006. Giant salamander occupancy varied by stream substrate type (i.e., consolidated vs. unconsolidated geologies) and was positively associated with stand age. Torrent salamander occupancy varied by species, was positively associated with channel gradient, and was reduced in the youngest and oldest sampled stands. Tailed frog occupancy was negatively associated with the presence of crayfish, negatively associated with low and high bankfull widths, and positively associated with stand age, although stands less than 5 years old had occupancy rates >50% in the absence of crayfish. Mean detection rates were less than 1 for all three genera (0.85, 0.66, and 0.63 for Dicamptodon, Rhyacotriton, and Ascaphus, respectively), which indicates that conclusions from previous research about relationships between SAA occupancy, environmental variables, and forest practices have an unknown element of uncertainty, particularly if detection rates co-vary with habitat change. We believe that our study is the first to present unbiased estimates of occupancy and detection parameters for SAA on forested landscapes in Oregon and Washington. 相似文献
479.
Starch granule size distribution of hard red winter and hard red spring wheat: Its effects on mixing and breadmaking quality 总被引:1,自引:0,他引:1
Starch was isolated from 98 hard red winter (HRW) wheat and 99 hard red spring (HRS) wheats. Granule size/volume distributions of the isolated starches were analyzed using a laser diffraction particle size analyzer. There were significant differences in the size distribution between HRW and HRS wheats. The B-granules (<10 μm in diameter) occupied volumes in the range 28.5–49.1% (mean, 39.9%) for HRW wheat, while HRS wheat B-granules occupied volumes in the range 37.1–56.2% (mean, 47.3%). The mean granule sizes of the distribution peaks less than 10 μm in diameter also showed a significant difference (HRW, 4.32 vs. HRS, 4.49 μm), but the mean sizes of the distribution peaks larger than 10 μm were not significantly different (21.54 vs. 21.47 μm). Numerous wheat and flour quality traits also showed significant correlation to starch granule size distributions. Most notably, protein content was inversely correlated with parameters of B-granules. Crumb grain score appeared to be affected by starch granule size distribution, showing significant inverse correlations with B-granules. Furthermore, the linear correlations were improved when the ratio of B-granules to protein content was used, and the polynomial relation was applied. There also appeared to be an optimum range of B-granules for different protein content flour to produce bread with better crumb grain. 相似文献
480.
Site-specific management of limiting nutrients in peanut (Arachis hypogaea) on the Texas High Plains
Rolf Färe Chenggang Wang A. Michael Schubert Kevin F. Bronson Jeff Johnson 《Precision Agriculture》2009,10(4):331-341
Nutrient data obtained from soil chemical tests were analyzed in an activity analysis model to identify limiting factors in
peanut production on the Texas High Plains. A production function was estimated for the study field, and limiting factors
were identified at individual sites where the production function indicated that yield did not respond. The estimated production
function also enabled us to conduct a cost-return analysis of variable- and blanket-rate fertilizer applications. The results
showed that peanut yields did not respond to most of the nutrients included in the study, which confirmed conclusions from
previous studies in the study region. Calcium and nitrogen were the only two limiting factors identified in this study. Significant
economic returns could be obtained by site-specific fertilizer application. The average economic return from variable-rate
calcium fertilizer application was $27.84 ha−1 and from blanket-rate it was $10.73 ha−1. The return from variable-rate nitrogen fertilizer application was about $20 ha−1 and from a blanket-rate it was about $14 ha−1. There seems to be quite a strong economic incentive to adopt variable-rate application for calcium and nitrogen fertilizer
application.
相似文献
Jeff JohnsonEmail: |