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361.
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   
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363.
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   
364.
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   
365.
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   
366.
Resveratrol, a well-known phytoalexin and antioxidant, is produced by the action of stilbene synthase (STS) in some plant species. Hop (Humulus lupulus L.) plants of the Tettnang variety were transformed with a gene encoding for STS from grapevine. Under the control of the constitutive 35S cauliflower mosaic virus promoter, expression of the transgene resulted in accumulation of resveratrol and high levels of its glycosylated derivatives in leaves and inflorescences. Piceid, the predominant derivative, reached a concentration of up to 560 microg/g of fresh weight (f.w.) in hop cones, whereas no stilbenes were detected in nontransformed controls (wild-type). In transgenic plants the amounts of alpha- and beta-acids, naringenin chalcone, and prenylated flavonoids did not change significantly when compared with nontransformed plants. Transgenic plants showed normal morphology and flower development as did the nontransformed controls. The results clearly show that in hop constitutive expression of sts interferes neither with plant development nor with the biosynthesis of secondary metabolites relevant for the brewing industry. Since resveratrol is a well-known phytoalexin and antioxidant, sts transgenic hop plants could display enhanced pathogen resistance against microbial pathogens, exhibit new beneficial properties for health, and open new venues for metabolic engineering.  相似文献   
367.
OBJECTIVE: To compare ground reaction forces (GRFs) measured by use of a pressure-sensitive walk-way (PSW) and a force plate (FP) and evaluate weekly variation in the GRFs and static vertical forces in dogs. ANIMALS: 34 clinically normal dogs and 5 research dogs with lameness. PROCEDURE: GRF data were collected from 5 lame and 14 clinically normal dogs by use of an FP and a PSW. Peak vertical force (PVF), vertical impulse (VI), and velocity measurements (determined by use of photocells and PSW data) were compared between groups. Peak vertical force, VI, stride length, ground phase time (ie, contact time), and static body weight distribution data were collected on 2 occasions, 1 week apart, in 20 different clinically normal dogs by use of a PSW; week-to-week variation in values was evaluated. RESULTS: Measurements of velocity derived by use of the photocells were not different from those derived by use of the PSW. For any 1 limb, values derived by use of the PSW were significantly lower than values derived with the FP. For values obtained by use of either technique, there were no differences between left and right limbs except for values of PVF measured via PSW in forelimbs. Values of PVF, VI, contact time, stride length, and static weight distribution generated by the PSW did not vary from week to week. CONCLUSIONS AND CLINICAL RELEVANCE: Values for GRFs varied between the FP and PSW. However, data derived by use of PSW were consistent and could be used to evaluate kinetic variables over time in the same dog.  相似文献   
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369.
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   
370.
The forest floor at high elevation spruce-fir sites from southern Vermont, U.S. to the Gaspé Peninsula, Québec, Canada was sampled and analyzed in 1979 and re-sampled and analyzed in 1996 to study temporal changes in the impacts of atmospheric pollutants. We determined organic matter mass, pH, and concentrations of Al, Ca, Fe, K, Mg, Na, Cd, Cu, Hg, Pb, and Zn for the litter (L = fresh litter plus Oi horizon) and fermentation plus humic horizons (F+H) (= Oe plus Oa horizons) of the forest floor. There were no trends for Al or Fe concentrations in the 1979 or 1996 L along the transect. Several sites had significantly lower Al and Fe values in 1996 than in 1979, likely indicating less mineral soil in the 1996 samples. The 1996 concentrations of Ca in L increased along the transect from 0.22% dry weight (dw) in Vermont to 0.60% dw in Québec. Concentrations of Mg in L were relatively constant along the transect. Neither Ca nor Mg changed at sites from 1979 to 1996, indicating unchanged base status. Concentrations of Cd did not vary spatially along the transect but decreased at all sites from 1979 to 1996. Cu and Zn did not vary spatially or with time. In 1979, the concentration of Hg in L ranged between 150 and 300 μg kg?1 dw, with no spatial gradient. By 1996, Hg concentrations were 25 to 50% lower in L, with decreases generally proportional to the concentration in 1979. The concentration of Pb in 1979 L decreased significantly from 200 mg kg?1 dw in southern Vermont to 60 mg kg?1 dw in Québec. By 1996, the Pb concentration in L ranged between 32 and 66 mg kg?1 dw with no spatial trend along the transect. Decreases in Pb concentrations at sites were proportional to the absolute value in 1979. The concentrations of Cd, Hg, and Pb have declined in litter from 1979 to 1996, indicating a decline in atmospheric deposition. Higher Hg and Pb accumulation rates to the southwest are suggested for the past as indicated by (F+H) concentrations and inventories of Hg and Pb. The decline of Pb in L is consistent with the decreased use of leaded gasoline starting in the 1970s; the declines in Cd and Hg probably reflect lower emissions over the same period. Declining concentrations of Cd, Hg, and Pb in L parallel those documented in recent lake and peat sediments in the northeastern United States.  相似文献   
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