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Vector-borne diseases, including canine heartworm disease (CHWD), are of major socioeconomic and canine health importance worldwide. Although many studies have provided insights into CHWD, to date there has been limited study of fundamental molecular aspects of Dirofilaria immitis itself, its relationship with the canine host, its vectors, as well as the potential of drug resistance to emerge, using advanced -omic technologies. This article takes a prospective view of the benefits that advanced -omics technologies will have toward understanding D. immitis and CHWD. Tackling key biological questions using these technologies will provide a "systems biology" context and could lead to radically new intervention and management strategies against heartworm.  相似文献   
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Two steers (approximately 195 kg) were each dosed with 62.5 or 130.6 mg/kg body weight sodium [36Cl]chlorate for three consecutive days. All excreta were collected during the dosing and 8 h withdrawal periods. The apparent radiochlorine absorption was 62-68% of the total dose with the major excretory route being urine. Parent chlorate was 65-100% of the urinary radiochlorine; chloride was the only other radiochlorine species present. Similarly, residues in edible tissues were composed of chloride and chlorate with chloride being the major radiolabeled species present. Chlorate represented 28-57% of the total radioactive residues in skeletal muscle; in liver, kidney, and adipose tissues, chlorate ion represented a smaller percentage of the total residues. Chlorate residues in the low dose steer were 26 ppm in kidney, 14 ppm in skeletal muscle, 2.0 ppm in adipose tissue, and 0.7 ppm in liver. These data indicate that sodium chlorate may be a viable preharvest food safety tool for use by the cattle industry.  相似文献   
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The effects of enriched CO2 atmosphere on partitioning of recently assimilated carbon were investigated in a plant-soil-microorganism system in which Lolium perenne seedlings were planted into cores inserted into the resident soil within a sward that had been treated with elevated CO2 for 9 consecutive years, under two N fertilisation levels (Swiss FACE experiment). The planted cores were excavated from the ambient (35 Pa pCO2) and enriched (60 Pa pCO2) rings at two dates, in spring and autumn, during the growing season. The cores were brought back to the laboratory for 14C labelling of shoots in order to trace the transfer of recently assimilated C both within the plant and to the soil and microbial biomass. At the spring sampling, high N supply stimulated shoot and total dry matter production. Consistently, high N enhanced the allocation of recently fixed C to shoots, and reduced it to belowground compartments. Elevated CO2 had no consequences for DM or the pattern of C allocation. At the autumn sampling, at high N plot, yield of L. perenne was stimulated by elevated CO2. Consistently, 14C was preferentially allocated aboveground and, consequently belowground recent C allocation was depressed and rhizodeposition reduced. At both experimental periods, total soil C content was similar in all treatments, providing no evidence for soil carbon sequestration in the Swiss Free Air CO2 Enrichment experiment (FACE) after 9 years of enrichment. Recently assimilated C and soil C were mineralised faster in soils from enriched rings, suggesting a CO2-induced shift in the microbial biomass characteristics (structure, diversity, activity) and/or in the quality of the root-released organic compounds.  相似文献   
56.
It is still unclear whether elevated CO2 increases plant root exudation and consequently affects the soil microbial biomass. The effects of elevated CO2 on the fate of the C and nitrogen (N) contained in old soil organic matter pools is also unclear. In this study the short and long-term effects of elevated CO2 on C and N pools and fluxes were assessed by growing isolated plants of ryegrass (Lolium perenne) in glasshouses at elevated and ambient atmospheric CO2 and using soil from the New Zealand FACE site that had >4 years exposure to CO2 enrichment. Using 14CO2 pulse labelling, the effects of elevated CO2 on C allocation within the plant-soil system were studied. Under elevated CO2 more root derived C was found in the soil and in the microbial biomass 48 h after labelling. The increased availability of substrate significantly stimulated soil microbial growth and acted as priming effect, enhancing native soil organic matter decomposition regardless of the mineral N supply. Despite indications of faster N cycling in soil under elevated CO2, N availability to plants stayed unchanged. Soil previously exposed to elevated CO2 exhibited a higher N cycling rate but again there was no effect on plant N uptake. With respect to the difficulties of extrapolating glasshouse experiment results to the field, we concluded that the accumulation of coarse organic matter observed in the field under elevated CO2 was probably not created by an imbalance between C and N but was likely to be due to more complex phenomena involving soil mesofauna and/or other nutrients limitations.  相似文献   
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The aim of this study was to examine the effects of amendments with leaf biomass on the development of tomato plants in a soil where root-knot nematodes (Meloidogyne mayaguensis) and/or a nematophagous fungus (Arthrobotrys oligospora, strain ORS 18697) had been inoculated. Six origins of leaf biomass were chosen: Acacia mangium, Acacia holosericea, Eucalyptus camaldulensis, Casuarina equisetifolia, Azadirachta indica and Sorghum vulgare. These leaf biomass types inhibited the development of the aerial parts of the tomato plants. This negative effect was not observed when the fungus was inoculated. On the contrary, plant growth was stimulated. Moreover, the antagonistic activity of Arthrobotrys oligospora was strengthened in the presence of ground leaf powder, especially that from Acacia holosericea. The effects of phenolic compounds on fungal growth and predatory activity and on plant growth are discussed.  相似文献   
59.
The endemic midwife toad of Mallorca (Alytes muletensis) is restricted to a small number of breeding populations in the mountainous northwest of the island. The decline of the species has been attributed to the impacts of introduced species such as the viperine snake (Natrix maura) and green frog (Rana perezi), and toads may be surviving only in areas that are suboptimal for these predators. The influence of landscape features (elevation, aspect and maximum slope) on the distribution of toads and associated predators was therefore investigated using GIS. The presence of toads was positively associated with steep slopes. At sites where they occurred with toads, the distribution of predators was negatively associated with elevation. Reproductive success within toad populations was strongly associated with the number of pools at each site, while reproductive success within individual pools was positively associated with elevation. These findings may be used to optimise the design and location of future reintroduction sites.  相似文献   
60.
Ten leguminous trees, four exotic species (Australian Acacia) and six indigenous species (three Sahelian Acacia spp. and three Sesbania spp.), were grown for 4 months in a natural Sahelian soil inoculated with or without the endomycorrhizal fungus, Glomus intraradices. In control trials, the determinant factor structuring the soil nematode fauna was the plant species, related plants having a similar influence on the nematode community in the soil. Soil nematode abundance increased from exotic acacias (3.3 g-1 dry soil) to native acacias (11.5 g-1 dry soil) and Sesbania species (17.6 g-1 dry soil). Plant feeding nematodes (mainly Scutellonema and Tylenchorhynchus) were significantly less abundant under exotic acacias (1.4 g-1 dry soil) than under native acacias (7.2 g-1 dry soil) or Sesbania species (7.3 g-1 dry soil). Bacterial feeding nematode density increased from exotic acacias (1.2 g-1 dry soil) to native acacias (3.0 g-1 dry soil) and Sesbania species (7.7 g-1 dry soil) as total densities. However, the differences in the structure of the nematode communities between plant groups were suppressed in the presence of the mycorrhizal fungus. In fact, no difference in nematode densities remained between plant groups when G. intraradices developed in several dominant taxa belonging to different trophic groups, particularly: Tylenchorhynchus, Apelenchina, Cephalobus and Dorylaimoidea. This study clearly indicated that inoculation with the arbuscular mycorrhizal fungus G. intraradices diminished the plant-specific effect on the structure of the soil nematode community.  相似文献   
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