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31.
Viruses may remain infectious outside the host cell for considerable time and represent a source of accidental infection if not properly inactivated. In this study, the survival of vesicular stomatitis virus (VSV) in suspension and dried on surfaces was analyzed. In addition, the sensitivity of VSV to disinfectants and physicochemical changes was investigated. VSV showed a notable stability in suspension at 4 °C with virus titers remaining high over several weeks. The presence of serum proteins had a stabilizing effect on virus infectivity, whereas elevated temperatures reduced survival times. VSV dried on polystyrene, glass or stainless steel surfaces remained infectious for at least 6 days at ambient temperature. VSV showed a remarkable resistance to extreme pH in particular in the alkaline range, but could be rapidly inactivated by heating at 55 °C or higher. The virus was highly sensitive to inactivation by commonly used disinfectants such as aldehydes, alcohols, and detergents. The high stability of VSV on surfaces and in suspension may facilitate dissemination of the virus in livestock by contaminated feeding and water troughs, hands, and milking equipment. This knowledge on the sensitivity of VSV to disinfectants will help to set up appropriate hygiene measures. 相似文献
32.
Bettina M Dunkel Pamela A Wilkins 《Veterinary Clinics of North America: Equine Practice》2004,20(1):107-126
A nutritional plan should be incorporated into every treatment plan of the critically ill patient. Weight loss and cachexia are the result of prevalence of catabolic processes over anabolic processes in addition to absolute or relative increased demands and decreased food intake. 相似文献
33.
Ainsworth DM Wagner B Franchini M Grünig G Erb HN Tan JY 《American journal of veterinary research》2006,67(4):669-677
OBJECTIVE: To evaluate time-dependent alterations in gene expression of chemokines in bronchial epithelium of recurrent airway obstruction (RAO)-affected horses and whether alterations resulted from increases in gene expression of interleukin (IL)-17 in cells isolated from bronchoalveolar lavage fluid (BALF). ANIMALS: 8 RAO-susceptible horses and 9 control horses. PROCEDURE: In 2 experiments, both groups of horses were evaluated after being maintained on pasture and after being stabled and fed dusty hay for 1, 14, 35, and 49 days (experiment 1) or 14 and 28 days (experiment 2). In experiment 1, gene expression of IL-8, chemokine (C-X-C motif) ligand 1 (CXCL1), granulocyte-macrophage colony-stimulating factor (GM-CSF), granulocyte colony-stimulating factor (G-CSF), and Toll-like receptor 4 (TLR4) in epithelium and IL-8, IL-17, and TLR4 in BALF cells was measured. In experiment 2, bronchial biopsy specimens were evaluated for IL-8 immunoreactivity. RESULTS: In RAO-susceptible horses after 14 days of challenge exposure, there was a 3- and 10-fold increase in gene expression of IL-8 for epithelial and BALF cells and an increase in IL-8 immunoreactivity in epithelial cells. Challenge exposure failed to alter gene expression of CXCL1, GM-CSF, G-CSF, and TLR4 in epithelial cells of any horses at any time point. During challenge exposure, gene expression of BALF cell IL-17 was downregulated in control horses (day 1) and upregulated in RAO-affected horses (day 35). CONCLUSIONS AND CLINICAL RELEVANCE: Epithelial-derived IL-8 may promote airway neutrophilia, but the inciting stimulus is unlikely to be IL-17 because upregulation of this gene is subsequent to that of IL-8 in epithelial cells. 相似文献
34.
Fekadu Wondimu Mekbib Firew Lakew Berhane Haussmann Bettina I. G. 《Journal of Crop Science and Biotechnology》2023,26(2):119-133
Journal of Crop Science and Biotechnology - Barley is one of the most important cereal crops cultivated over a wider environment in the diverse agro-ecologies in Ethiopia. Study on genotype by... 相似文献
35.
Jonne Rodenburg Lammert Bastiaans Ad. H. C. M. Schapendonk Peter E. L. van der Putten Aad van Ast Niels J. Dingemanse Bettina I. G. Haussmann 《Euphytica》2008,160(1):75-87
Striga hermonthica (Del.) Benth. is a parasitic weed on tropical cereals causing serious yield losses in Africa. The use of host crop varieties
with improved resistance and tolerance against this parasite is a key component of an integrated control strategy. Breeding
for tolerance is however seriously hampered by the absence of reliable and yet practical selection measures. The observation
that the photosynthetic rate of tolerant genotypes is less sensitive to Striga infection was used as a starting point to search for suitable selection measures. In a greenhouse pot experiment the effect
of Striga infection on the photosynthesis of four sorghum (Sorghum bicolor [L.] Moench) genotypes, differing in Striga tolerance level, was measured at three moments in time (26, 48 and 75 days after sowing). Genotypes were CK60-B, E36-1, Framida
and Tiémarifing. Measurements involved CO2-assimilation (A) and three chlorophyll fluorescence characteristics (electron transport rate through photosystem II [ETR], photochemical [Pq] and non-photochemical quenching [NPq]). Striga infection negatively affected A, ETR and Pq. Based on A and Pq, genotypes with superior levels of tolerance (Tiémarifing) could be discriminated from genotypes with superior level of resistance
(Framida). Both A and Pq showed high heritabilities and consequently clear and predictable differences between genotypes. Using discriminative ability,
heritability and cost effectiveness as main criteria, photochemical quenching (Pq) was concluded to possess the highest potential to serve as indirect selection measure for host plant tolerance to Striga. Screening should preferably be conducted at relatively high Striga infestation levels, between Striga emergence and host plant flowering. 相似文献
36.
Prediction of deoxynivalenol and zearalenone concentrations in Fusarium graminearum inoculated backcross populations of maize by symptom rating and near‐infrared spectroscopy 下载免费PDF全文
Thomas Miedaner Sen Han Bettina Kessel Milena Ouzunova Tobias Schrag Friedrich H. Utz Albrecht E. Melchinger 《Plant Breeding》2015,134(5):529-534
Gibberella ear rot (GER) caused by Fusarium graminearum is a destructive disease in maize of temperate regions resulting in yield reduction and contamination by the mycotoxins deoxynivalenol (DON) and zearalenone (ZON). We wanted to analyse whether prediction of DON and ZON concentrations is feasible either by GER severity ratings or by near‐infrared spectroscopy (NIRS). We analysed 80 and 102 lines developed by backcrossing doubled‐haploid lines from segregating populations to the resistant and susceptible parent, respectively, by artificial infection at three locations in Germany and France. Both backcross (BC) populations differed substantially in their means for all traits with significant (P < 0.01) genotypic variances. DON and ZON concentrations measured by immunotests were significantly (P < 0.01) correlated with each other and with GER severity within each BC population (0.6 ≤ r ≤ 0.9, P < 0.01). DON concentration measured by immunotest and NIRS significantly correlated (r ≈ 0.9, P < 0.01). In conclusion, DON and ZON concentrations could be reliably predicted by GER severity. Additional NIRS analysis of DON concentration might be useful for the positively selected fraction. 相似文献
37.
The sequestration of carbon in soil is not completely understood, and quantitative information about the rates of soil organic carbon (SOC) turnover could improve understanding. We analyzed the effects of the uneven distribution of crop residues after harvest of silage maize on C and N losses (CO2‐C, dissolved organic carbon (DOC) and nitrogen (DON), and NO3–) from a Haplic Phaeozem and on the occurrence of priming effects induced by the decomposition of accumulated maize residues. Soil columns were taken from a continuous maize (since 1961) field after harvest i) between maize stalk rows (Mbare), ii) within the maize rows including a standing maize stalk (Mstalk), and iii) from a continuous rye (since 1878) field after tillage (rye stalk and roots were mixed into the Ap horizon). The soil columns were incubated for 230 days at 8 °C with an irrigation rate of 2 mm 10–2 M CaCl2 per day. Natural 13C abundance was used to distinguish between maize‐derived C (in SOC and maize residues) and older C originating from former C3 vegetation. The uneven distribution of maize residues resulted in a considerably increased heterotrophic activity within the maize rows as compared with soil between seed rows. Cumulative CO2 production was 53.1 g CO2‐C m–2 for Mstalk and 23.3 g CO2‐C m–2 for Mbare. The contribution of maize‐derived C to the total CO2 emission was 83 % (Mstalk) and 67 % (Mbare). Calculated as difference between CO2‐C release from Mstalk and Mbare, 19 % of the maize residues (roots and stalk) in Mstalk were mineralized during the incubation period. There was no or only a marginal effect of the accumulation of maize residues in Mstalk on leaching of DOC, DON, and NO3–. Total DOC and DON leaching amounted to 2.5 g C m–2 and 0.16 g N m–2 for Mstalk and to 2.1 g C m–2 and 0.12 g N m–2 for Mbare. The contribution of maize‐derived C to DOC leaching was about 25 % for Mstalk and Mbare. Nitrate leaching amounted to 3.9 g NO3–‐N m–2 for Mstalk and to 3.5 g NO3–‐N m–2 for Mbare. There was no priming effect induced by the decomposition of fresh maize residues with respect to CO2 or DOC production from indigenous soil organic carbon derived from C3 vegetation. 相似文献
38.
Anja Nüsse Deborah Linsler Michael Kaiser Dorothee Ebeling Bettina Tonn Johannes Isselstein 《Archives of Agronomy and Soil Science》2017,63(12):1776-1783
The effects of different grazing pressures (GPs) on soil properties are not sufficiently understood. The objectives were to analyse the effects of three different extensive GPs on stocks of soil organic C and total N, soil microbial biomass C, basal respiration and mineral N in three different soil depths of a long-term pasture in Central Germany (FORBIOBEN field trial). No significant (p ≤ 0.05) effects of GP on weighted stocks of soil organic C, total N, soil microbial biomass C, mineral N and basal respiration rate were observed, suggesting that the C and N cycles are coupled in the three grazing treatments. Oxalate soluble Fe contents explained a marked part of the variation of soil organic C (multiple linear regression: R2 = 0.64) and total N contents (R2 = 0.64) in the soils, whereas almost all of the variability of soil microbial biomass C contents and basal respiration was explained by soil organic C contents. Overall, variabilities of soil organic C and N contents were largely explained by oxalate soluble Fe contents, whereas grazing intensity did not affect the C and N dynamics. 相似文献
39.
Phytotoxicity of Thallium (Tl) in Culture Solution Part 2: Effects of Tl(III) on the Growth and Heavy Metal Contents of Pea and Field Bean Plants The effects of Tl(NO3)3 and Tl(III)EDTA on growth and heavy metal contents of pea plants (Pisum sativum L. cv. Aromata) and field bean plants (Vicia faba L. cv. Hangdown) were compared in hydroponic culture experiments. In the presence of Tl(NO3)3, the essential heavy metals were available to the plants in their ionic forms. When Tl(III)EDTA was present the essential heavy metals were available as chelated complexes. Dry matter production of the pea plants was inhibited to a greater extent by TI(II1)EDTA than by Tl(NO3)3. The distribution of TI within the plant was unaffected by the accompanying anion, however an increase of the TI content of the stems and the leaves was observed in the presence of TI(II1)EDTA. The micronutrients exhibited different interactions with TI(II1). In the presence of increasing concentrations of Tl(NO3)3 the Mn content of each organ and the Zn content of the roots were lowered, but the Zn content of the stems was increased. Increasing concentrations of TI(II1)EDTA resulted only in a decrease of the Mn content of the roots, but in an increase of the contents of Fe and Mn within the stems, and Fe, Mn, Zn, and Cu within the leaves. The increases may be due to concentration by growth inhibition. In contrast to pea plants, growth of field bean plants was inhibited only by TI(N03)). The field bean plants retained most of the TI within the roots independent of the TI compound in the solution. Chelation of TI(II1) resulted in higher TI contents of both the roots and the stems, but equal or reduced TI contents of the leaves. Whereas increasing concentrations of Tl(NO3)3 reduced the Mn content of each organ as well as the Zn content of the roots and the leaves, TI(II1)EDTA only reduced the Mn content of the roots. 相似文献
40.