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101.
Adonna Fleming Leslie M. Delserone Elaine Nowick 《Journal Of Agricultural & Food Information》2013,14(3):213-239
The Ogallala Aquifer is a key water resource for several U. S. states. TransCanada, a Canadian company, proposes to construct the Keystone XL pipeline to transport tar sands crude oil from Alberta to refineries in Texas; one proposed route would bury the pipeline in the Aquifer, raising water quality and environmental concerns. A rich inventory of information about the Aquifer predates the current controversy. This article presents a key subset of an extensive, ongoing bibliography: 128 citations to gray literature about the Ogallala Aquifer in Nebraska, which are inaccessible online and/or held in only a few libraries. The authors present several examples to illustrate the relevance of this gray literature to current events, comment on difficulties encountered during the bibliographic harvest and the identification of this subset, and reiterate the need for planned preservation through digitization of historical (print) gray literature. 相似文献
102.
CASE HISTORY: Eight mohua, or yellowheads (Mohoua ochrocephala), were held in a large open aviary over the summer months of 2003–2004, following their capture for captivebreeding purposes. Two birds died of transportation trauma shortly after arrival, one became ill and died a month later, and another four died within a 2-week period in February 2004. The eighth bird also became ill at this time but survived for a year following treatment with chloroquine and doxycycline. CLINICAL AND PATHOLOGICAL FINDINGS: The affected birds were depressed, lethargic and dyspnoeic. Necropsy of three birds showed a slightly pale and swollen liver and spleen. Impression smears of the liver of one bird revealed schizonts resembling Plasmodium spp. within the cytoplasm of many hepatocytes, which was confirmed histopathologically. Similar protozoal organisms were seen within splenic histiocytes and pulmonary endothelial cells of 5/6 birds. Electron microscopy identified these as protozoal schizonts containing merozoites of similar size and structure to those of Plasmodium spp. DIAGNOSIS: The birds were infected with a protozoal haemoparasite resembling Plasmodium spp.; asexual stages within hepatocytes and endothelial cells of the lung and spleen were typical of this organism. CONCLUSIONS AND CLINICAL RELEVANCE: The mohua captured from west Otago were highly susceptible to avian malaria as they came from an isolated population that was likely to be naïve and have had no previous contact with this organism. The birds were probably infected by bites from mosquitoes feeding off local populations of blackbirds subsequently found to be infected with Plasmodium spp. 相似文献
103.
Long-term organic farming fosters below and aboveground biota: Implications for soil quality, biological control and productivity 总被引:3,自引:1,他引:3
Klaus Birkhofer T. Martijn Bezemer Jaap Bloem Michael Bonkowski Sren Christensen David Dubois Fleming Ekelund Andreas Fließbach Lucie Gunst Katarina Hedlund Paul Mder Juha Mikola Christophe Robin Heikki Setl Fabienne Tatin-Froux Wim H. Van der Putten Stefan Scheu 《Soil biology & biochemistry》2008,40(9):2297-2308
Organic farming may contribute substantially to future agricultural production worldwide by improving soil quality and pest control, thereby reducing environmental impacts of conventional farming. We investigated in a comprehensive way soil chemical, as well as below and aboveground biological parameters of two organic and two conventional wheat farming systems that primarily differed in fertilization and weed management strategies. Contrast analyses identified management related differences between “herbicide-free” bioorganic (BIOORG) and biodynamic (BIODYN) systems and conventional systems with (CONFYM) or without manure (CONMIN) and herbicide application within a long-term agricultural experiment (DOK trial, Switzerland). Soil carbon content was significantly higher in systems receiving farmyard manure and concomitantly microbial biomass (fungi and bacteria) was increased. Microbial activity parameters, such as microbial basal respiration and nitrogen mineralization, showed an opposite pattern, suggesting that soil carbon in the conventional system (CONFYM) was more easily accessible to microorganisms than in organic systems. Bacterivorous nematodes and earthworms were most abundant in systems that received farmyard manure, which is in line with the responses of their potential food sources (microbes and organic matter). Mineral fertilizer application detrimentally affected enchytraeids and Diptera larvae, whereas aphids benefited. Spider abundance was favoured by organic management, most likely a response to increased prey availability from the belowground subsystem or increased weed coverage. In contrast to most soil-based, bottom-up controlled interactions, the twofold higher abundance of this generalist predator group in organic systems likely contributed to the significantly lower abundance of aboveground herbivore pests (aphids) in these systems. Long-term organic farming and the application of farmyard manure promoted soil quality, microbial biomass and fostered natural enemies and ecosystem engineers, suggesting enhanced nutrient cycling and pest control. Mineral fertilizers and herbicide application, in contrast, affected the potential for top-down control of aboveground pests negatively and reduced the organic carbon levels. Our study indicates that the use of synthetic fertilizers and herbicide application changes interactions within and between below and aboveground components, ultimately promoting negative environmental impacts of agriculture by reducing internal biological cycles and pest control. On the contrary, organic farming fosters microbial and faunal decomposers and this propagates into the aboveground system via generalist predators thereby increasing conservation biological control. However, grain and straw yields were 23% higher in systems receiving mineral fertilizers and herbicides reflecting the trade-off between productivity and environmental responsibility. 相似文献
104.
Julie H DeMarco Darryl J Heard Gregory J Fleming Brad A Lock Timothy J Scase 《Journal of zoo and wildlife medicine》2002,33(2):147-150
Forty dog-faced fruit bats (Cynopterus brachyotis) were administered 1 drop of 1% ivermectin topically as part of a routine physical exam and deworming program, and 11 developed sudden generalized paresis. Six of the bats recovered within 24-48 hr, and the remaining 5 were presented recumbent and weak to the University of Florida Veterinary Medical Teaching Hospital. Ivermectin toxicosis was suspected, and the admitted bats died or were euthanatized within 3-5 days of the development of clinical signs despite supportive care. Three of the dead bats had renal tubular necrosis. 相似文献
105.
Sheep were immunised with Corynebacterium pseudotuberculosis toxoid formulated as a monocomponent vaccine with aluminium adjuvant or in combination with 5 clostridial antigens, and also in the combined form with sodium selenate. Immunised and control sheep were experimentally infected 16 days after vaccination and slaughtered and inspected after a further 3 months to determine their resistance to infection. All 3 vaccines afforded an equal and high level of protection; 91% of vaccinated sheep exhibiting no lesions of caseous lymphadenitis compared with 51.5% affected sheep in the control group. Average lesion counts were 1.2 per affected vaccinated sheep and 4.5 per affected control sheep. Antitoxin responses to the clostridial toxoids incorporated in the combined vaccines were not affected by inclusion of the C pseudotuberculosis toxoid or the sodium selenate. 相似文献
106.
Immunisation against ovine caseous lymphadenitis: comparison of Corynebacterium pseudotuberculosis vaccines with and without bacterial cells 总被引:2,自引:0,他引:2
Sheep were immunised with Corynebacterium pseudotuberculosis vaccines prepared from cell-free toxoid or from toxoid with formalin-killed cells of C pseudotuberculosis added. Resistance of sheep to infection was tested 6 months after immunisation by inoculation with caseous lymphadenitis pus. The outcome was assessed 3 months later by slaughter and inspection of the sheep for lesions of caseous lymphadenitis. immunised sheep were adequately protected against infection as shown by a significant reduction in the number of sheep exhibiting lesions compared with control sheep, and by fewer abscesses in affected vaccinated sheep than in affected control sheep. The protective potency of the vaccines was not improved by the inclusion of cells of C pseudotuberculosis. 相似文献
107.
108.
Abnormal behavior, suggestive of rabies, is not an unusual finding in woodchucks (Marmota monax). Necropsy records, rabies antibody tests, and necropsy examinations performed by the authors indicate that migration of ascarid larvae usually is responsible for the abnormal behavior, and that rabies is an infrequent finding. Baermannization of brain tissue is suggested for a differential diagnosis. 相似文献
109.
110.
1. Two experiments were carried out to investigate responses in performance and bone compositional and structural characteristics in broilers fed diets containing 4 concentrations of vitamin D3 (5, 20, 125 and 250 microg cholecalciferol/kg) at different concentrations of calcium, available phosphorus and vitamin A. 2. In experiment 1, body weight and tibia breaking strength were maximised at 14d with 250 microg vitamin D3/kg, tibia ash was maximised with 125 microg vitamin D3/kg. A high incidence of tibial dyschondroplasia (TD) was decreased to very low levels with 125 microg vitamin D/kg. 3. At 42d, performance and bone characteristics showed no response to vitamin D3 concentrations above 20 microg/kg. 4. Dietary vitamin A within the range 2-4 to 4.5 mg retinol/kg did not show any interaction with vitamin D3 status at either age. 5. In experiment 2, responses to vitamin D3 were strongly influenced by dietary calcium/available phosphorus. With 13 g calcium and 5 g available phosphorus/kg, performance and bone characteristics responded to vitamin D3 concentrations up to 125 microg/kg but more was needed at less optimal concentrations of calcium and available phosphorus. TD incidence was minimised with 250 microg/kg. 6. This study shows that high dietary concentrations of vitamin D3 can prevent TD. It is concluded that the vitamin D3 requirement of broilers up to 14 d of age at optimal dietary calcium and available phosphorus concentrations may be in the range 35 to 50 microg/kg for cortical bone quality and up to 250 microg/kg for prevention of TD. The vitamin D3 requirement for cortical bone quality after 14 d is not higher than 20 microg/kg. These requirements are much higher than earlier estimates and may be related to higher calcium requirements of modern broiler genotypes. Current regulations limiting maximum vitamin D3 concentrations in broiler starter diets may need to be reviewed. 相似文献