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991.
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993.
Transboundary animal disease viruses such as foot-and-mouth disease virus (FMDV) and African swine fever virus (ASFV) are highly contagious and cause severe morbidity and mortality in livestock. Proper disinfection during an outbreak can help prevent virus spread and will shorten the time for contaminated agriculture facilities to return to food production. Wood surfaces are prevalent at these locations, but there is no standardized method for porous surface disinfection; commercial disinfectants are only certified for use on hard, nonporous surfaces. To model porous surface disinfection in the laboratory, FMDV and ASFV stocks were dried on wood coupons and exposed to citric acid or sodium hypochlorite. We found that 2% citric acid was effective at inactivating both viruses dried on a wood surface by 30 min at 22°C. While 2000 ppm sodium hypochlorite was capable of inactivating ASFV on wood under these conditions, this chemical did not meet the 4-log disinfection threshold for FMDV. Taken together, our data supports the use of chemical disinfectants containing at least 2% citric acid for porous surface disinfection of FMDV and ASFV. 相似文献
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995.
Lobo L Pinheiro-Vieira A Gomes JL Canada N Ribeiro L Costa PD Oliveira P Bussadori C 《Journal of the American Animal Hospital Association》2012,48(1):54-59
A 1 yr old male Estrela mountain dog was evaluated as a part of a screening program for dilated cardiomyopathy. The dog came from a family with a history of dilated cardiomyopathy but was asymptomatic. Occult dilated cardiomyopathy and sino-atrial dysfunction were diagnosed based on echocardiography and electrocardiography. These two disorders may be associated given that related dogs have been diagnosed with the same disorders. The dog has remained asymptomatic for 4 years following initial evaluation. 相似文献
996.
Ramón Perea Alfonso San Miguel María Martínez-Jauregui María Valbuena-Carabaña Luis Gil 《European Journal of Forest Research》2012,131(3):623-631
We examine whether different guilds of foragers remove seeds differentially according to seed quality (seed size and insect
infestation) and seed location (habitat and microhabitat) in a mixed oak-beech forest. Video recordings indicated that the
wood mouse (Apodemus sylvaticus) was first to encounter seeds. Foragers preferred acorns to beechnuts, large to small size and sound to infested. Nevertheless,
infested seeds were removed by rodents even when sound seeds were present. Seeds that were not preferred by scatter-hoarding
rodents remained longer on the ground and were more vulnerable to predation and desiccation (4% moisture loss per day). However,
seeds that were removed by scatter-hoarders were moved away from their mother trees (96%) and cached individually (32%), increasing
their moisture content (3% per day). Buried seeds, simulating scatter-hoarding behavior, experienced only a 17% removal after
4 months. Seed removal differences among habitats were not due to habitat attributes but to the spatial distribution of rodent-preferred
microhabitats. Thus, a significant lower seed removal was observed under the tree canopy with no shrubs. However, seed removal
in forest gaps with deadwood cover was not significantly different from the preferred microhabitat (under shrub cover). In
pure beech forests, seed removal by rodents only occurred under Ilex aquifolium (the only perennial cover) and under woody debris. This study concludes that seed quality and seed location determine the
contribution of different removers (predators vs. dispersers), their seed selection and their removal speed, leading to different
seed fates which will eventually affect tree regeneration. 相似文献
997.
Jorge Aldea Fernando Martínez-Peña Luis Diaz-Balteiro 《European Journal of Forest Research》2012,131(6):1991-2003
Some non-timber forestry products, such as mushrooms, have not typically been included in forest management plans, creating a scenario whereby timber production is the main objective and fungal resources are an afterthought. However, in certain forests, wild mushrooms reach a significant level of production. This paper researches a strategic forest management plan that would include the production of both timber and mushrooms as principal objectives while still adhering to constraints normally considered within forest management. A case study is provided featuring two main groups of edible wild mushrooms, where the two aforementioned objectives have been optimised individually. Lacking a satisfactory solution for the decision-maker, a model based on multi-criteria decision analysis (compromise programming) has been constructed to yield more attractive solutions. Information regarding mushrooms is based on the actual amount collected in the forest and not on potential production. Measured in monetary terms, mushroom production can be easily compared with timber production. Income associated with mushroom production is equal to approximately 20 % of that generated by timber throughout the planning horizon when final inventory and regulation constraints are imposed. 相似文献
998.
Edmond Pasho J. Julio Camarero Martín de Luis Sergio M. Vicente-Serrano 《European Journal of Forest Research》2012,131(6):1797-1807
We lack information regarding the main factors driving growth responses to drought in tree species with different vulnerability against this stressor and considering sites with contrasting climatic conditions. In this paper, we identify the main drivers controlling growth response to a multi-scalar drought index (Standardized Precipitation Index, SPI) in eight tree species (Abies alba, Pinus halepensis, Quercus faginea, Pinus sylvestris, Quercus ilex, Pinus pinea, Pinus nigra, Juniperus thurifera). We sampled forests growing across a pronounced climatic gradient under Mediterranean conditions in north-eastern Spain. To summarize the patterns of growth responses to drought, we used principal component analysis (PCA). To determine the main factors affecting growth responses to drought, correlation and regression analyses were carried out using a set of abiotic (climate, topography, soil type) and biotic (Normalized Difference Vegetation Index, Enhanced Vegetation Index, tree-ring width, diameter at breast height) predictors and the PCs loadings as response variables. The PCA analysis detected two patterns of growth responses to drought corresponding to xeric and mesic sites, respectively. The regression analyses indicated that growth responses to drought in xeric forests were mainly driven by the annual precipitation, while in mesic sites the annual water balance was the most important driver. The management of Mediterranean forests under the forecasted warmer and drier conditions should focus on the main local factors modulating the negative impacts of drought on tree growth in xeric and mesic sites. 相似文献
999.
Rojo-Montejo S Collantes-Fernández E López-Pérez I Risco-Castillo V Prenafeta A Ortega-Mora LM 《Veterinary research》2012,43(1):62
The parasite Neospora caninum is an important abortifacient agent in cattle worldwide. At present, the development of an effective and safe vaccine against bovine neosporosis is of great relevance. Recently, a new isolate of N. caninum (Nc-Spain 1 H) which was obtained from the brain of an asymptomatic congenitally infected calf, exhibited non-virulent behaviour in mouse and bovine infection models. The aim of this study was to determine the safety and efficacy of Nc-Spain 1 H when used as a vaccinal isolate in well-established BALB/c models of congenital and cerebral neosporosis. Mice were subcutaneously immunised twice at 3-week intervals and were challenged with 2 × 106 tachyzoites of the virulent Nc-Liv isolate. After immunisation with live Nc-Spain 1 H tachyzoites, no parasitic DNA was detected in the dams’ brains before challenge and microsatellite analysis performed in PCR-positive mice showed that the profiles corresponded to the challenge isolate Nc-Liv, indicating the Nc-Spain 1 H isolate to be a safe vaccine candidate. The efficacy of the live vaccine was evaluated in the first experiment after the immunisation of mice with 5 × 105 live Nc-Spain 1 H tachyzoites. This immunisation protocol significantly reduced the neonatal mortality to 2.4%, reduced the vertical transmission from 89.1% to 2.3% and completely limited the cerebral infection. These results were associated with a Th1-type immune response. In the second experiment, the effect of various immunising doses was established using ten-fold dilutions of the tachyzoites (from 5 × 105 to 5 × 10). In all the cases, congenital protection rates above 60% were observed, and the mice that were immunised with the lowest dose (5 × 10) presented the highest protection rate (86%). Moreover, low immunising doses of Nc-Spain 1 H induced an IgG2a response, and high parasitic doses induced an IgG1 response. These results evidence the safety and the efficient protection that was conferred by Nc-Spain 1 H against congenital neosporosis, even when the mice were immunised with low parasitic doses. 相似文献
1000.
Certain plant extracts are bioactive substances of some foods or traditional herbs, known to possess antioxidant, antibacterial, and perhaps immunoregulatory effects. This study investigated the in vitro anti-inflammatory effects of 7 plant extracts (anethol, capsicum oleoresin, carvacrol, cinnamaldehyde, eugenol, garlicon, and turmeric oleoresin) on porcine alveolar macrophages collected from weaned pigs (n = 6 donor pigs) by bronchoalveolar lavage. The experimental design for this assay was a 2 [with or without 1 μg lipopolysaccharide (LPS)/mL] × 5 (5 different amounts of each plant extract) factorial arrangements in a randomized complete block design. The application of plant extracts were 0, 25, 50, 100, and 200 μg/mL, except for cinnamaldehyde and turmeric oleoresin, which were 0, 2.5, 5, 10, and 20 μg/mL. The 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT) assay was used to determine the number of live cells, Griess assay was applied to detect nitric oxide (NO) production, and ELISA was used to measure tumor necrosis factor-α (TNF-α), IL-1β, transforming growth factor-β (TGF-β), and IL-10 in the cell culture supernatants of macrophages. The LPS increased (P < 0.001) the secretion of TNF-α, IL-1β, and TGF-β. Without LPS, anethol and capsicum oleoresin increased (linear, P < 0.001) cell viability of macrophages, whereas other plant extracts reduced (linear, P < 0.001) it. Anethol, capsicum oleoresin, and carvacrol enhanced (linear, P < 0.001) the cell proliferation of LPS-treated macrophages. Without LPS, anethol, capsicum oleoresin, cinnamaldehyde, or turmeric oleoresin stimulated TNF-α secretion, whereas all plant extracts except eugenol enhanced IL-1β concentration in the supernatants of macrophages. However, all plant extracts suppressed (linear, P < 0.001) TNF-α, and all plant extracts except turmeric oleoresin decreased (linear, P < 0.05) IL-1β secretion from LPS-treated macrophages. Anethol and capsicum oleoresin decreased (linear, P < 0.001) TGF-β from macrophages in the absence of LPS, but the other plant extracts increased it. Anethol, capsicum oleoresin, and carvacrol also suppressed (linear, P < 0.001) TGF-β from macrophages with LPS stimulation; the other plant extracts enhanced or did not affect it. The anti-inflammatory cytokine, IL-10, was not detected in any supernatants. Only very low amounts of NO were detected in the supernatants of macrophages. In conclusion, the TNF-α results indicate all plant extracts tested here may have anti-inflammatory effects to varying degrees. 相似文献