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441.
Onderka DK Papp-Vid G Perry AW 《The Canadian veterinary journal. La revue veterinaire canadienne》1992,33(8):539-543
Acute mortality occurred in two unrelated rabbitries. In the rabbits examined, an unidentified herpesvirus caused lesions that have not been reported previously in this species. The primary lesions were multifocal hemorrhagic dermatitis on the face and back, localized pneumonia, and severe splenic necrosis. Large eosinophilic, intranuclear inclusion bodies that were observed in tissue sections of skin, spleen, and lung were identified as herpes-like viral particles by electron microscopy, and herpesvirus was cultured on rabbit kidney cells. Intramuscular injection of tissue culture fluid containing virus resulted in mortality and severe illness in two seven-week-old domestic rabbits four and six days postinfection, respectively. The gross and microscopic lesions were reproduced and herpeslike viral inclusions were observed in skin lesions. Herpesvirus was recovered from lung, trachea, spleen, liver, and from the thigh muscle at the site of inoculation. The experimental infection also activated severe pasteurella septicemia. The herpesvirus isolate needs further characterization. 相似文献
442.
A systematic representation of crop rotations 总被引:1,自引:0,他引:1
M.S. Castellazzi G.A. Wood P.J. Burgess J. Morris K.F. Conrad J.N. Perry 《Agricultural Systems》2008,97(1-2):26-33
Crop rotations are allocations by growers of crop types to specific fields through time. This paper aims at presenting (i) a systematic and rigorous mathematical representation of crops rotations; and (ii) a concise mathematical framework to model crop rotations, which is useable on landscape scale modelling of agronomical practices. Rotations can be defined as temporal arrangements of crops and can be classified systematically according to their internal variability and cyclical pattern. Crop sequences in a rotation can be quantified as a transition matrix, with the Markovian property that the allocation in a given year depends on the crop allocated in the previous year. Such transition matrices can represent stochastic processes and thus facilitate modelling uncertainty in rotations, and forecasting of the long-term proportions of each crop in a rotation, such as changes in climate or economics. The matrices also permit modelling transitions between rotations due to external variables. Computer software was developed that incorporates these techniques and was used to simulate landscape scale agronomic processes over decadal periods. 相似文献
443.
Michael E. L. Perry Walter H. Schacht Gregory A. Ruark James R. Brandle 《Agroforestry Systems》2009,77(1):23-35
A study to determine the feasibility of producing forage for grazing livestock under trees was conducted as a step toward
evaluating the potential for silvopasture systems in the northern and central Great Plains. The effects of overstory leaf
area index (LAI), percentage understory light transmittance (LT), and soil moisture (SM) on yield and crude protein (CP) of
big bluestem [Andropogon gerardii Vitman; (BB)], smooth bromegrass [Bromus inermis Leyss.; (SB)], and mixtures with birdsfoot trefoil [Lotus corniculatus L.; (BFT)] were examined. The study was conducted in both Scotch pine (Pinus sylvestris L.) and green ash (Fraxinus pennsylvancia Marsh.) tree plantations, at the University of Nebraska Agriculture Research and Development Center near Mead, Nebraska.
Thirty-six plots representing a wide range of canopy cover were selected at each location and seeded in April 2000 to BB,
SB, or mixtures with BFT. Measurements of LAI, LT, and SM were taken throughout the 2001-growing season and plots were harvested
in June and September 2001. Soil moisture generally did not explain much of the variability in yield or CP for BB, SB, or
BFT. Cumulative LAI or LT averaged over the growing season was the best predictor of yield or CP, particularly under the pine.
Yields of BB and SB increased as LAI decreased or LT increased. Conversely, the CP of BB and SB increased as LT decreased
for both the June and September harvests. Both BB and SB maintain relatively high productivity under partial shading; however,
BFT yields were low at LT levels below 75%.
At the time of the research, the senior author was research assistant, Department of Agronomy and Horticulture, University
of Nebraska-Lincoln, Lincoln, NE 68853-0915. 相似文献
444.
Arkadiusz Malkus Qijian Song Perry Cregan Edward Arseniuk Peter P. Ueng 《European journal of plant pathology / European Foundation for Plant Pathology》2009,124(4):681-690
A genetic linkage map of the fungal pathogen Phaeosphaeria nodorum, the causal agent of stagonospora nodorum blotch disease of wheat, was created. A total of 152 ascospore-derived progeny
from a single pseudothecium, which resulted from a cross of two opposite mating type isolates, Sn37-1 and S-81-B13B, was analysed
with AFLP, RAPD, ISSR, expressed sequence tag (EST)-derived microsatellite primers and sequence tagged site markers developed
from specific genes. The genetic linkage map consisted of 276 molecular markers, and included markers developed from five
genes [Glyceraldehyde 3-phosphate dehydrogenase (gpd), malate synthase (Mls1), mannitol 1-phosphate dehydrogenase (Mpd1), mating type (MAT1) and RNA polymerase II (RPB2)], which were assigned to 21 major linkage groups (LGs). The total length of the 21 major LGs was 1,932.1 centiMorgans (cM)
with an average spacing of 6.88 cM between loci. The idiomorph mating type gene (MAT1) loci was placed in LG 2 and was closely linked to RAPD marker A4-680. On the other hand, 24 molecular markers and four gene
loci [β-glucosidase (bgl1), histidinol dehydrogenase (Hdh2), mannitol 1-phosphate dehydrogenase (Mpd2), and xylanase (Xyl 10-2)] were dispersed in 11 minor LGs. The segregation ratio of the xylanase (Xyl 10-1) locus was distorted and not mapped. This is the first genetic linkage map reported for this important foliar pathogen of
wheat. In combination with the genomic sequence of P. nodorum strain SN15 (), the availability of a genetic linkage map of this organism would be an important tool to investigate quantitative trait
loci (QTL) of biologically important phenotypes and for positional cloning. 相似文献
445.
Katherine M. Phillips David M. Ruggio Mehdi Ashraf‐Khorassani Ronald R. Eitenmiller Sungeun Cho Linda E. Lemar Charles R. Perry Pamela R. Pehrsson Joanne M. Holden 《Cereal Chemistry》2010,87(1):42-49
Twelve popular ready‐to‐eat breakfast cereals fortified with folic acid were sampled in the United States in 2006, and the data have been incorporated into the USDA National Nutrient Database for Standard Reference. Cereals were collected from three statistically selected retail outlets in each of four primary census regions, and four composites of each product were prepared using random groupings of three locations each. Folic acid was determined using a validated LC‐MS method, with 13C‐folic acid as an internal standard, after trienzyme treatment and solid phase extraction. A cereal reference material (AACC VMA399) was analyzed as a control. Selected samples were also assayed using the standard microbiological method, with and without trienzyme extraction, to generate an estimate of endogenous folate. On average, as shown on the label, folate content was underestimated. In seven cereals, folate was within 5% of the declared value; in four cereals, it was 5–20% higher; and in two cereals, it was >20% greater, representing –75 to +69 μg/serving (mean 17) of the label value, equivalent to –19% to +17% of the 400 μg/daily value. The microbiologically determined folic acid was higher than LC‐MS by 10–67% (mean 40%). Therefore, use of label values might underestimate folate intake from some breakfast cereals. 相似文献
446.
Genetics and mapping of quantitative traits for nodule number, weight, and size in soybean (Glycine max L.[Merr.]) 总被引:1,自引:0,他引:1
Sadal Hwang Jeffery D. Ray Perry B. Cregan C. Andy King Marilynn K. Davies Larry C. Purcell 《Euphytica》2014,195(3):419-434
Soybean research has found that nodule traits, especially nodule biomass, are associated with N2 fixation ability. Two genotypes, differing in nodule number per plant and individual nodule weight, KS4895 and Jackson, were mated to create 17 F3- and 80 F5-derived RILs. The population was mapped with 664 informative markers with an average distance of less than 20 cM between adjacent markers. Nodule traits were evaluated in 3-year field trials. Broad-sense heritability for nodule number (no. plant?1), individual nodule dry weight (mg nodule?1), individual nodule size (mm nodule?1), and total nodule dry weight (g plant?1) was 0.41, 0.42, 0.45, and 0.27, respectively. Nodule number was negatively correlated with individual nodule weight and size. Nodule number, individual nodule weight, and size are major components which likely contributed to increased total nodule weight per plant. Composite interval mapping (CIM) identified eight QTLs for nodule number with R2 values ranging from 0.14 to 0.20. Multiple interval mapping (MIM) identified two QTLs for nodule number, one of which was located close to the QTL identified with CIM. Six QTLs for individual nodule weight were detected with CIM, and one QTL was identified with MIM. For nodule size, CIM identified seven QTLs with R2 values ranging from 0.14 to 0.27. Five QTLs for total nodule weight were detected with CIM, one of which was located close to a QTL identified with MIM. These results document the first QTL information on nodule traits in soybean from field experiments utilizing a dense, complete linkage map. 相似文献
447.
Brian W. Brooks Cheryl L. Lutze-Wallace Leann L. MacLean Evgeny Vinogradov Malcolm B. Perry 《Canadian journal of veterinary research》2010,74(1):18-24
Lipopolysaccharides (LPSs) from Taylorella equigenitalis, the causative agent of contagious equine metritis, and T. asinigenitalis were compared by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). Lipopolysaccharide profiles of 11 T. equigenitalis strains were similar, but different from the profiles of 3 T. asinigenitalis strains, and the profiles of 2 T. asinigenitalis strains were similar to each other. The serological specificities of the LPSs from these 14 strains were examined by immunoblotting and enzyme-linked immunosorbent assay with monoclonal antibodies (MAbs) to the LPSs of the T. equigenitalis and T. asinigenitalis type strains and T. asinigenitalis strain 2329–98. A MAb to T. equigenitalis LPS O-polysaccharide (O-PS) (M2560) reacted with LPSs from all T. equigenitalis strains but did not react with LPSs from the 3 T. asinigenitalis strains or with 43 non-Taylorella bacteria. Three MAbs to the T. asinigenitalis type strain LPS O-PS or core epitopes (M2974, M2982, M3000) reacted with the homologous strain and T. asinigenitalis strain Bd 3751/05, but not with any of the other bacteria. Five MAbs to T. asinigenitalis 2329–98 LPS O-PS or core epitopes (M2904, M2907, M2910, M2923, M2929) reacted only with this strain. Proton nuclear magnetic resonance spectra of the O-PSs of the type strains of T. equigenitalis and T. asinigenitalis provided fingerprint identification and differentiation of these 2 organisms. The serological results were consistent with our previous finding that the O-antigen of the type strain of T. equigenitalis, being a linear polymer of disaccharide repeating [→4)-α-L-GulpNAc3NAcA-(1→4)-β-D-ManpNAc3NAcA-(1→] units, differs from that of the T. asinigenitalis O-antigen polymer that is composed of repeating [→3)-β-D-QuipNAc4NAc-(1→3)-β-D-GlcpNAmA-(1→] units. Lipopolysaccharide O-PS could be a specific marker for identification and differentiation of T. equigenitalis and T. asinigenitalis, and provide the basis for the development of specific detection assays for T. equigenitalis. 相似文献
448.
S. Kottler J.R. Middleton J. Perry J.S. Weese L.A. Cohn 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2010,24(1):132-139
Background: A higher prevalence of methicillin-resistant Staphylococcus aureus (MRSA) colonization is reported in healthcare workers compared with nonhealthcare workers.
Hypothesis: The prevalence of MRSA colonization differed in people and pets in households with healthcare workers as compared with households without healthcare workers.
Subjects: A person and 1 dog or cat from 586 households defined as either a nonhealthcare (n = 213), veterinary healthcare (n = 211), or human healthcare (n = 162) worker household.
Methods: Prospective cross-sectional study. Samples from humans and pets were cultured in vitro. Staphylococcus aureus was identified as methicillin sensitive (MSSA) or MRSA with mec A polymerase chain reaction. Pulsed-field gel electrophoresis and spa -typing were used to characterize relatedness of S. aureus and MRSA and assign USA types.
Results: The prevalence of MSSA and MRSA in humans was 21.5% (126/586) and 5.63% (33/586), respectively, and 7.85% (46/586) and 3.41% (20/586), respectively, in pets. There were no differences in prevalences of either MSSA or MRSA between household types. The proportion of MRSA among all S. aureus isolates in humans and pets was 20.8% (33/159) and 30.3% (20/66), respectively. In <1.0% (4/586) of households, the same strain of MRSA was found in both a person and a pet.
Conclusions and Clinical Importance: There were no differences in the prevalences of MSSA or MRSA between healthcare worker and nonhealthcare worker households. Pets and people colonized with S. aureus were as likely to be colonized with MRSA. Colonization of a person and their pet with the same strain of MRSA was rare. 相似文献
Hypothesis: The prevalence of MRSA colonization differed in people and pets in households with healthcare workers as compared with households without healthcare workers.
Subjects: A person and 1 dog or cat from 586 households defined as either a nonhealthcare (n = 213), veterinary healthcare (n = 211), or human healthcare (n = 162) worker household.
Methods: Prospective cross-sectional study. Samples from humans and pets were cultured in vitro. Staphylococcus aureus was identified as methicillin sensitive (MSSA) or MRSA with mec A polymerase chain reaction. Pulsed-field gel electrophoresis and spa -typing were used to characterize relatedness of S. aureus and MRSA and assign USA types.
Results: The prevalence of MSSA and MRSA in humans was 21.5% (126/586) and 5.63% (33/586), respectively, and 7.85% (46/586) and 3.41% (20/586), respectively, in pets. There were no differences in prevalences of either MSSA or MRSA between household types. The proportion of MRSA among all S. aureus isolates in humans and pets was 20.8% (33/159) and 30.3% (20/66), respectively. In <1.0% (4/586) of households, the same strain of MRSA was found in both a person and a pet.
Conclusions and Clinical Importance: There were no differences in the prevalences of MSSA or MRSA between healthcare worker and nonhealthcare worker households. Pets and people colonized with S. aureus were as likely to be colonized with MRSA. Colonization of a person and their pet with the same strain of MRSA was rare. 相似文献
449.
450.
Gerstein MB Lu ZJ Van Nostrand EL Cheng C Arshinoff BI Liu T Yip KY Robilotto R Rechtsteiner A Ikegami K Alves P Chateigner A Perry M Morris M Auerbach RK Feng X Leng J Vielle A Niu W Rhrissorrakrai K Agarwal A Alexander RP Barber G Brdlik CM Brennan J Brouillet JJ Carr A Cheung MS Clawson H Contrino S Dannenberg LO Dernburg AF Desai A Dick L Dosé AC Du J Egelhofer T Ercan S Euskirchen G Ewing B Feingold EA Gassmann R Good PJ Green P Gullier F Gutwein M Guyer MS Habegger L Han T Henikoff JG 《Science (New York, N.Y.)》2010,330(6012):1775-1787