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Extensive afforestation took place in Ireland during the twentieth century and the forest cover currently represents about 10% of the land area. However, approximately 50% of this forest is Sitka spruce, a non-native species introduced from the North Western United States of America. Little is known about the microarthopods of these forests and the current study examined the mites (Oribatida and Gamasina) occurring in the canopy, moss (both on the soil surface and in the canopy) and soil of oak, ash, Scots pine and Sitka spruce forests in Ireland to compare the mite assemblages in each and to determine the associations between forest type and the form of constituent microhabitats in determining the structure of this fauna. There were significant differences between the diversity and species composition of the assemblages in the different forest types with the largest species richness occurring in oak forest and the smallest in first rotation Sitka spruce forest. Analysis of our data, together with the results from other studies, suggest that the differences arise because the variation between the architecture of the tree species is reflected in the structure of microhabitats such as the form of the bark and the extent of moss cover. Thus while the ultimate factors affecting the variation in the mite fauna may be the form of the microhabitats, these are intrinsic properties of the forests associated directly with the species of tree. Finally, our results do not support the view that exotic species will necessarily have low biodiversity of mites than native forests. 相似文献
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Germán J Cantón Frank Katzer Stephen W Maley Paul M Bartley Julio Benavides-Silván Javier Palarea-Albaladejo Yvonne Pang Sionagh H Smith Mara S Rocchi David Buxton Elisabeth A Innes Francesca Chianini 《Veterinary research》2014,45(1):11
Infection with Neospora caninum stimulates host cell-mediated immune responses, which may be responsible for placental damage leading to bovine abortion. The aim of this study was to compare immune responses in the bovine placenta, following experimental infection in different stages of pregnancy. Placentomes were examined by immunohistochemistry and inflammation in early gestation was generally moderate to severe, particularly in the placentas carrying non-viable foetuses, whereas it was milder in later stages, mainly characterised by the presence of CD3+, CD4+ and γδ T-cells. This distinctive cellular immune response may explain the milder clinical outcome observed when animals are infected in later gestation. 相似文献
226.
Javier Regidor-Cerrillo David Arranz-Solís Julio Benavides Mercedes Gómez-Bautista José Antonio Castro-Hermida Mercedes Mezo Valentín Pérez Luis Miguel Ortega-Mora Marta González-Warleta 《Veterinary research》2014,45(1):10
This work studies the influence of Neospora caninum intra-species diversity on abortion outcome, infection dynamics in terms of parasite dissemination and peripheral-local immune responses in pregnant cattle. Animals were intravenously inoculated at day 70 of pregnancy with 107 tachyzoites of two isolates showing marked differences in virulence in vitro and in pregnant mouse models: Nc-Spain7, a high virulence isolate, and Nc-Spain8, a low-to-moderate virulence isolate. After inoculation, pregnancy was monitored, and dams were culled when foetal death was detected. Foetal mortality occurred in all infected heifers between days 24 and 49 post-infection (pi), however, it was detected sooner in Nc-Spain7-infected animals (median day = 34) than those inoculated with Nc-Spain8 (median day = 41) with a trend towards significance (P < 0.11). Similar histological lesions were observed in placentomes and in most of the foetuses from the two infected groups. However, parasites were more frequently detected in the placenta and foetuses by PCR and in the foetal brain by immunohistochemistry in Nc-Spain7-infected animals. Specific antibodies were detected starting at day 13 post-infection in all infected cattle, with higher IgG levels in Nc-Spain7-infected group. IFN-γ and IL-4 profiles also varied between infected groups in PBMC stimulation assays. Infected animals showed significant increases in their cytokine mRNA levels (IFN-γ, IL-4, IL-10, IL-12p40 and TNF-α) in the caruncle at time of foetal death. Differences between the infected groups were also observed for cytokine profiles. These results demonstrate the influence of the N. caninum isolate on foetal death outcome, infection dynamics and immune responses in cattle. 相似文献
227.
Gregorio Egea Luis Pérez-Urrestarazu Julio González-Pérez Antonio Franco-Salas Rafael Fernández-Cañero 《Urban Forestry & Urban Greening》2014,13(3):475-483
Living walls (LW) are vertical greening systems that are becoming popular due to their multiple social and environmental benefits. When LW are installed indoors, a lightening system is often required to ensure an appropriate plant development. This work assesses the performance of three artificial lighting systems on six indoor LW [0.7 m (wide) × 0.7 m (high)] placed at two distances from the light source. The plant species selected for the tests were Soleirolia soleirolii and Spathiphyllum wallisii, which are frequently used in indoor LW. Three different lamps were used in the experiment: incandescent (IL), fluorescent (FL) and metal halide (MHL) lamps, all of them with an input electric power of ≈250 W. Differences in plant growth were only observed when the LW were close to the light source (about 1 m) but not at greater distances (≈1.5 m). IL had the poorest performance. Despite the lower photosynthetic photon flux density efficiency of FL compared with MHL, FL light enabled plants placed in the upper LW (closer to light source) reached similar size to those grown under MHL. Plant quality attributes were generally not affected by light type or the distance to light source. IL and FL generated higher total water losses (i.e. transpiration plus evaporation) than MHL on a LW basis. When expressed per unit of LW area covered by vegetation, FL and MHL reduced water consumption by 34% and 56%, respectively, as compared to IL. Overall, our results indicate that both FL and MHL outperform IL and have a similar ornamental performance, whereas MHL are more advantageous than FL in terms of water consumption and annual cost. 相似文献
228.
Martín Varisco Cecilia Crovetto Julia Colombo Julio Vinuesa Susana Risso 《Journal Of Aquatic Food Product Technology》2020,29(3):229-237
ABSTRACTThe squat lobster Munida gregaria has been recognized as a potential resource in several countries. However, data about its composition and nutritional value are scarce. This study provides information about the nutrients and nutritional quality of M. gregaria meat. Meat yield, proximate composition, cholesterol content, and fatty acid (FA) and amino acid (AAs) profiles were analyzed, and nutritional quality indexes were estimated. The average meat yield was 9.93%. The yearly average of the proximate composition of the M. gregaria meat (g/100 g meat) was moisture = 77.6, protein = 13.7, lipids = 3.84, and ash = 2.19. The average annual cholesterol content was 6.60 mg/100 g. The predominant FA (%) was C20:5ω3 (23.6), followed by C18:1ω9c (20.9), C22:6ω3 (18.5), and C16:0 (16.3); the unsaturated fatty acids were 72.8% of the total FA. The main AAs (g/100 g protein) were glutamic acid (15.1), leucine (9.47), and aspartic acid (8.51). Regarding the nutritional quality, the polyunsaturated FA/saturated FA ratio (1.99), ω3/ω6 ratio (8.62), atherogenic index (0.26), thrombotic index (0.56), hypocholesterolemic/hypercholesterolemic ratio (4.07), and polyene index (2.58) showed that M. gregaria meat provides lipids that are beneficial to the human diet. Moreover, M. gregaria meat provides high-quality proteins, which are well balanced in their essential AAs composition. 相似文献
229.
Gustavo Balmelli Sofía Simeto Nora Altier Virginia Marroni Julio J. Diez 《New Forests》2013,44(2):249-263
Eucalyptus globulus is the most important forest species in Uruguay, with more than 250,000 ha of commercial plantations. Despite its high susceptibility to diseases, production losses caused by foliar diseases have not been properly quantified in this country. This study analyzes the effects of foliar damage on growth and survival using data from a progeny test of E. globulus naturally infected by Teratosphaeria leaf disease and eucalypt rust (Puccinia psidii). The severity of leaf spots and defoliation were quantified 8 months after planting and tree growth and mortality were evaluated 2, 4 and 6 years later. The trial had a high incidence of foliar damage, with a mean leaf spot severity of 28.7% and a mean defoliation of 37%. The greatest impact of foliar damage, both on growth rate and mortality, occurred in the first 2 years after damage was assessed. During this period, leaf spot severity less than 40% and defoliation below 50% did not affect growth, while survival was affected when leaf damage was 70% or greater. By the sixth year both stem growth and survival were affected by severe foliar damage (spotting or defoliation of 80% or more), with a loss of up to 25% in diameter and an accumulated mortality over 70%. It has been established for the first time that under the intensive Uruguayan productive conditions, E. globulus trees can tolerate a relatively high degree of leaf spotting or defoliation but severe foliar damage in the first months can cause considerable production losses, putting at risk the economical viability of this species. 相似文献
230.
Chile eradicated classical swine fever (CSF) in April 1998, following a 17-year eradication programme. The authors describe biosecurity levels of pig farms in Chile after the eradication of CSF. A formal survey was administered to 50 large integrated pig farms, which represented almost 60% of the swine population. The main topics on the questionnaire were production, health management, biosecurity, insurance and information about CSF outbreaks in the past. Biosecurity practices were analysed according to the criteria stated by Barcelo and Marco in 1998. A scoring system to measure biosecurity was designed and pig farms were classified according to this score. An adjusted specific measure is discussed as a potential indicator of risk for disease infections. The authors explore associations between biosecurity herd size and insurance policy against CSF. 相似文献