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391.
392.
Luiz Henrique Saes Zobiole Rubem Silvério de Oliveira Junior Jamil Constantin Robert John Kremer Denis Fernando Biffe 《Journal of plant nutrition》2013,36(2):268-287
Glyphosate-resistant (GR) soybeans have continuously increased; however, this expansion significantly increased the use of glyphosate and therefore, in some cases, has resulted in injury symptoms observed in GR soybean, known as “yellow flashing”. Previous reports of interference of glyphosate with nutrient availability and utilization by GR soybean may be linked to this injury symptom. Also, because glyphosate interferes with amino acid synthesis, supplementation with exogenous amino acids may help GR soybean recover from adverse effects of glyphosate. Therefore, an experiment was designed to evaluate different amino acid concentrations. Near-isogenic and GR soybean varieties were grown in the greenhouse in two soils with and without glyphosate at different rates and amino acids were foliarly applied with and without glyphosate. In general, the photosynthetic variables, nutrient contents, and shoot and root dry biomass parameters were affected by glyphosate, however, use of amino acid formulations suppressed harmful effects of glyphosate on these parameters. 相似文献
393.
Marie Peeters Denis Verwilghen Didier Serteyn Marc Vandenheede 《Journal of Veterinary Behavior: Clinical Applications and Research》2012,7(5):311-321
Horse handling and veterinary examination can induce hazardous stress reactions. Such reactions occur especially in young and less-trained horses, particularly stallions, and make their handling a risk for breeders, grooms, and medical staff. Moreover, these stressful situations will affect the animal’s health and welfare. Because stress reactivity is thought to be partly determined by genetic factors, scientists, veterinarians, and breeders are likely to be interested in adding temperament assessments to stallion selection schemes, as it is already done in some countries. This study assesses young stallions’ temperament and its comparison with their stress reactions during a standardized veterinary examination for studbook admission. The assessment consists of a general examination, a lameness examination including flexion tests, an endoscopy of the upper airway, and a standardized radiological examination. During the years 2008 and 2009, 93 stallions were evaluated. Stallions were observed from the moment they were unloaded from the trailer at the clinic until the end of veterinary examinations. In addition to the behavioral observations made by the experimenter, each staff member in charge of the examination filled in a short questionnaire about the horse’s temperament and the “easiness of manipulation” for the performed examinations. Breeders were asked to complete a longer questionnaire about their horse’s temperament. The assessments of “aggressiveness,” “sociability,” and “learning level” temperament traits were the most consistent, as shown by the significant Spearman correlations between judges’ assessments. Undesirable behaviors during veterinary examinations leading to handling difficulties were associated with a low “easiness of manipulation” score assessed by the clinical staff. These low “easiness of manipulation” scores were positively correlated to temperament traits such as “anxiousness” and “aggressiveness” and negatively correlated to others such as “sociability” or “learning level.” Temperament assessment and behavioral observations can therefore be used to anticipate behaviors that make a horse difficult to handle during veterinary examinations. Thus, it may be important to include temperament assessment as a feature in the selection of breeding stallions—as already practiced for some breeds in some countries. Such evaluations may promote the welfare of horses and ease of handling as well as safety for the handler. 相似文献
394.
395.
Plasmopara halstedii, the causal agent of downy mildew of sunflower, is an oomycete listed as a quarantine pathogen. This obligate parasite resides in a quiescent state in seeds of sunflower and can be spread from seed production areas to areas of crop production by international seed trade. To prevent the spread or the introduction of potentially new genotypes or fungicide-tolerant strains, an efficient method to detect P. halstedii in sunflower seed is required. This work reports the optimization of a real-time detection tool that targets the pathogen within sunflower seeds, and provides statistically validated data for that tool. The tool proved to be specific and inclusive, based on computer simulation and in vitro assessments, and could detect as few as 45 copies of target DNA. A fully optimized DNA extraction protocol was also developed starting from a sample of 1,000 sunflower seeds, and enabled the detection of <1 infected seed/1,000 seeds. To ensure reliability of the results, a set of controls was used systematically during the assays, including a plant-specific probe used in a duplex quantitative polymerase chain reaction that enabled the assessment of the quality of each DNA extract. 相似文献
396.
Denis Rusjan Robert Veberi? Maja Mikuli?-Petkov?ek 《European journal of plant pathology / European Foundation for Plant Pathology》2012,133(4):965-974
The study was carried out on phytoplasma susceptible grapevine variety ‘Chardonnay’ (Vitis vinifera L.). The changes in total and individual phenolics, with a focus on hydroxycinnamic acids, flavanols and flavonol contents, were studied in phytoplasma-symptomatic and non-symptomatic berries of Bois noir (BN) infected and uninfected vines. Evident responses to BN infection at veraison have been monitored in a decreased accumulation of caftaric and coutaric acids, p-coumaroyl hexose, procyanidin B1, procyanidin trimer as well as of quercetin-3-O-glucoside, quercetin-3-O-glucuronide and quercetin-3-O-xyloside. At berry softening BN infection statistically increased the content of total phenolics, hydroxycinnamic acids and flavanols, but decreased the flavonol contents, especially at phytoplasma-symptomatic berry skins. Later, at harvest, the BN infection caused an additional significant decrease of coutaric acid and p-coumaroyl pentose contents, moreover of procyanidin B1 and procyanidin dimmers (1, 2, and 3), trimer, kaempferol-3-O-glucoside and of most identified quercetins, except of quercetin-3-O-xyloside. At harvest, non-symptomatic berries from infected plants showed similar dynamics in the total phenolic content compared to berry skins from uninfected plants, but in total flavanols and flavonols content similarity to those symptomatic was observed. The latter decreases grape quality and its antioxidant potential. The Bois noir disease showed specific, local and growth-phase-induced responses regarding the content of phenolics in berry skins, where in particular the differences between phytoplasma-symptomatic and non-symptomatic grapes have to be underlined. 相似文献
397.
Malogolovkin A Yelsukova A Gallardo C Tsybanov S Kolbasov D 《Veterinary microbiology》2012,158(3-4):415-419
African swine fever is one of the most important viral diseases of pigs and which caused significant economic damage on the pig production worldwide. Nowadays, it is still present on the African continent, in Transcaucasus countries (TCC), on Island of Sardinia and in Russia. Outbreaks of the disease have been reported in Russia for the last four years, affected especially the Southern Federal District of the country. Since 2010, a new outbreak area has been observed in the Northwestern Federal District. In order to study the evolution of African swine fever virus (ASFV) isolates, strains were collected in the Russian Federation from 2007 to 2011 and investigated by means of partial sequencing and fragment length polymorphism. In detail, 7 variable regions, namely B646L, E183L, I196L, B602L, I73R/I329R, I78R/I215L and KP86R were investigated. Phylogenetic analyses revealed 100% nucleotide identity of B646L and E183L gene sequences of all examined isolates. All isolates formed one genetic cluster within genotype II. Moreover, no amplified fragment length polymorphism (AFLP) was observed for B602L, I196L, I73R/I329R, and I78R/I215L genes. The flanking primers used to amplify the KP86R gene failed to amplify a product in all the isolates. The obtained data strongly suggests that only one ASFV virus variant caused the outbreaks from 2007 to 2011 in the territory of the Russian Federation. 相似文献
398.
Denis M Parlane NA Lacy-Hulbert SJ Summers EL Buddle BM Wedlock DN 《Veterinary immunology and immunopathology》2006,114(1-2):111-120
The aim of this study was to compare the ability of milk macrophages and macrophages from the mammary gland secretions during the mid-dry period for their interaction with the mastitis-causing Streptococcus uberis. We also aimed to determine if S. uberis induced the release of the cytokine tumour necrosis alpha (TNF-alpha) and the bactericidal moiety nitric oxide (NO) from milk macrophages of lactating cows and macrophages from the mammary gland secretions at the mid-dry period. Macrophages were isolated from the mammary gland secretions of cows during the mid-lactation or mid-dry period, and compared with blood monocytes for their interaction with the important mastitis-causing pathogen S. uberis. When infected in vitro with S. uberis, milk macrophages from lactating cows with S. uberis released modest amounts of the cytokine tumour necrosis factor alpha (TNF-alpha) (139 pg/ml) and the bactericidal moiety nitric oxide (NO) (3-4 microM of nitrite). Blood monocytes from lactating cows released significantly higher amounts of TNF-alpha (345 +/- 143 pg/ml) and NO (7 +/- 2 microM of nitrite) after interaction with S. uberis, compared to milk macrophages (P < 0.01 for both TNF-alpha and NO). Stimulation of blood monocytes with the cytokine interferon-gamma (IFN-gamma) enhanced significantly the release of NO and TNF-alpha, but IFN-gamma did not significantly enhance the production of NO and TNF-alpha by milk macrophages from lactating cows. Milk macrophages from all lactating cows failed to kill S. uberis efficiently, and this lack of killing was unaffected by prior treatment with gamma interferon (IFN-gamma) (P > 0.05). Rather, S. uberis multiplied significantly inside infected milk macrophages from lactating cows, with a two-fold increase in bacterial numbers at 2 h post-infection. Milk macrophages from lactating cows were able however, to kill a significant proportion (50-60%, P < 0.01) of phagocytosed Staphylococcus aureus. Blood monocytes from all cows were found to exert significant bactericidal activity against S. uberis. There were no significant differences in the bactericidal activity of milk macrophages obtained from lactating cows with low somatic cell counts (SCC; < 10(5) ml(-1)) compared with those with a mildly elevated SCC (> 10(5) ml(-1)) (P > 0.05). In contrast, mammary gland secretion macrophages isolated from the same cows in the mid-dry period killed a significant proportion of phagocytosed S. uberis (50-65% of ingested S. uberis killed, P < 0.01) although cytokine production in response to in vitro bacterial infection was low. We conclude that the bactericidal activity of mammary gland secretion macrophages against a virulent strain of S. uberis is low during the lactation period. In addition, our data indicate that S. uberis is not a strong inducer of NO and TNF-alpha in macrophages from the milk or mammary gland secretions of cows during the drying off period. Finally, IFN-gamma does not activate milk macrophages or macrophages from cows during the lactating period or mammary gland secretions during the drying off period. 相似文献
399.
400.
P F Solter W E Hoffmann L L Hungerford J P Siegel S H St Denis J L Dorner 《American journal of veterinary research》1991,52(10):1738-1742
Assay procedures for determining serum haptoglobin concentration and ceruloplasmin oxidase activity in dogs were validated, and reference values were established. Serum haptoglobin concentration is reported as milligrams per deciliter of cyanmethemoglobin binding capacity, whereas serum ceruloplasmin oxidase activity was determined by use of p-phenylenediamine as substrate. Both assays were used to analyze serum samples from 288 dogs. In each dog's case record, clinical history and final diagnosis were evaluated to determine whether the dog had an inflammatory condition. Complete blood cell counts were performed in 265 dogs, using simultaneously collected blood samples. Plasma fibrinogen concentration was determined for 161 dogs. A positive correlation (P less than 0.01) for serum haptoglobin concentration and for ceruloplasmin oxidase activity, compared with WBC counts, segmented neutrophil and band neutrophil counts, and plasma fibrinogen concentration. Ceruloplasmin oxidase activity and haptoglobin concentration were up to 6 times more sensitive than fibrinogen concentration or leukocyte counts in detecting inflammation. Specificity of ceruloplasmin oxidase activity was comparable to fibrinogen concentration and leukocyte counts, whereas haptoglobin concentration was found to be slightly less specific. Specificity of haptoglobin concentration improved slightly (from 0.82 to 0.88) when dogs with a history of glucocorticoid administration were excluded from analysis. Predictive value of a negative test result (haptoglobin concentration less than 125 mg/dl; ceruloplasmin oxidase activity less than 20 IU/L) and predictive value of a positive test result for haptoglobin concentration and ceruloplasmin activity were comparable to or better than fibrinogen concentration or various oxidase leukocyte counts in detection of inflammation in a variety of disease conditions.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献