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81.
82.
F. Kidd C. West D. G. Griffiths N. A. Potter 《The Journal of Horticultural Science and Biotechnology》2013,88(3):179-191
The volatile oil contents of dried leaves of Majorana hortensis, Melissa officinalis, Ocimum basilicum, Origanum vulgare, Salvia officinalis and Thymus vulgaris reached maximum values in summer. Different harvest dates are required in order to obtain the highest yields of dried leaves ha-1, the highest levels of volatile oil in the dried leaves, and the highest yields of volatile oil ha-1. The upper parts of balm, oregano and sage plants yielded the most dried leaves, but the lower parts showed the highest levels of volatile oil in the dried leaves. 相似文献
83.
A total of 763 faecal samples were collected from western grey kangaroos (Macropus fuliginosus) in Western Australia and screened for the presence of Cryptosporidium by PCR at the 18S ribosomal RNA (rRNA) locus. Samples that were positive at the 18S locus were also amplified at the actin locus. The overall prevalence was 9.3% (71/763). At the 18S rRNA locus, sequences were obtained for 28 of the 71 positives. Sequence analysis identified four species; Cryptosporidium fayeri in seven isolates, Cryptosporidium marcopodum in four isolates, Cryptosporidium xiaoi in six isolates and a novel genotype (kangaroo genotype I) in eleven isolates. Analysis at the actin locus confirmed the genetic distinctness of the novel genotype. The results of the present study indicate that in addition to C. fayeri and C. marcopodum, kangaroos may be capable of being infected with a wider range of Cryptosporidium species and genotypes including livestock species such as C. xiaoi. The novel genotype identified in the kangaroos most likely represents a cryptic species that requires further analyses to confirm its species status. 相似文献
84.
Wisner AL Desin TS Lam PK Berberov E Mickael CS Townsend HG Potter AA Köster W 《Veterinary microbiology》2011,153(3-4):274-284
Several structural components of the type III secretion systems (T3SS) encoded by Salmonella pathogenicity island (SPI)-1 and SPI-2 are exposed to the host's immune system prior to/during the infection/invasion process, making them potential vaccine candidates. In this study we evaluated whether chickens vaccinated with SPI-2 T3SS components could mount a significant humoral immune response (as measured by serum IgG titres) and whether these antibodies could be transferred to progeny (as measured by egg yolk IgG titres), and whether vaccinates and progeny of vaccinates could be protected against challenge with SE. The results of our studies show that vaccinated chickens do produce high levels of SPI-2 T3SS specific serum IgG that they are able to transfer to their progeny. It was demonstrated that vaccinates and progeny of vaccinates had lower overall countable recovered Salmonella enterica subspecies enterica serovar Enteritidis (SE) per bird in most situations. 相似文献
85.
86.
Water, Air, &; Soil Pollution - The flux of metals at the tidal limits of major rivers are an important metric of freshwater contaminant transfer to marine habitats, reported in Northeast... 相似文献
87.
A disorder of Michigan potatoes tentatively called speckle leaf is associated, in part, with air pollution injury. The disease is characterized by reduced yields following early vine maturity, premature vine death, and yellowing of the lower leaves. Necrotic spots developed on the upper surface of leaves, followed by bronzing, and upward leaf rolling. Severely affected leaves became chlorotic and remained attached to the stem. Potato plants were grown in two plastic houses through which was blown either ambient field air or ambient air filtered through activated charcoal. Plants grown in the plastic house receiving ambient air developed symptoms similar to nearby field plants. Plants grew normally in filtered ambient air and remained free of speckle leaf and air pollution injury symptoms. The potato varieties Haig, Norchip, and Superior were most sensitive, Sebago was intermediate, and Kennebec and Katahdin were most tolerant. Tobacco plants in ambient non-filtered air developed symptoms typical of ozone injury. Bean leaves became bronzed with brown necrotic flecks on both surfaces, and severely affected leaves dropped. Neither tobacco nor bean was affected in the filtered air. 相似文献
88.
Summer cover crop impacts on soil percolation and nitrogen leaching from a winter corn field 总被引:1,自引:0,他引:1
The impacts of a leguminous summer cover crop (sunn hemp; Crotalaria juncea) on nitrogen leaching from a corn (Zea mays L.) field was evaluated by direct measurements of soil water content and nitrogen balance components, complemented by direct and inverse modeling as an exploratory tool to better understand water flow and nitrogen balances in the soil. Water and nitrogen inputs and outputs were measured during winter corn production in an experimental field located in the south Miami-Dade basin in southern Florida (USA). Data from the last two seasons (2001-2002 and 2002-2003) of a 4-year study are presented. The field was divided into six 0.13 ha plots. One-half of the plots were rotated with sunn hemp (CC plots) during the summer while the remaining plots were kept fallow (NC plots). Sweet corn management was uniform on all plots and followed grower recommended practices. A numerical model (WAVE) for describing water and agrochemical movement in the soil was used to simulate water and nitrogen balances in both types of plots during the corn seasons. The hydrodynamic component of WAVE was calibrated with soil water data collected continuously at three depths, which resulted in accurate soil water content predictions (coefficients of efficiency of 0.85 and 0.91 for CC and NC plots, respectively). Measured components of the nitrogen balance (corn yields, estimated nitrogen uptake, and soil organic nitrogen) were used to positively assess the quality of the nitrogen simulation results. Results of the modeled water balance indicate that using sunn hemp as a cover crop improved the soil physical conditions (increase in soil water retention) and subsequently enhanced actual crop evapotranspiration and reduced soil drainage. However, nitrogen simulation results suggest that, although corn nitrogen uptake and yields were slightly higher in the CC plots than in the NC plots, there were net increases of soil N content that resulted in increased N leaching to the shallow aquifer. Therefore, the use of sunn hemp as cover crop should be coupled with reductions in N fertilizer applied to the winter crop to account for the net increase in soil N content. 相似文献
89.
C.D. Corn BS G.D. Potter PhD T.W. Odom PhD O.C. Jenkins PhD 《Journal of Equine Veterinary Science》1993,13(10)
Blood acid-base and electrolyte status was studied in four sedentary Miniature Horses treated with 200, 300, 400 and 500 mg of sodium bicarbonate (NaHCO3) per kg of body weight (BW). Arterial blood was collected before treatment with NaHC03 and each hour for 5 h after treatment. All treatments resulted in an increase in blood pH, bicarbonate (HCO3−) concentration and base excess (BE) by 1 h post-dosage, which continued through the 5th hour (P < .05). Treatment with 200 mg NaHC03/kg BW resulted in less elevated blood HCO3− concentrations (P < .03) and BE values (P < .01) when compared to the other treatments. Following dosing with NaHCO3, plasma Na+ concentrations increased among all treatments but declined to initial values by 3 h post-treatment. The 200 mg NaHCO3/kg BW dosage resulted in the smallest increases in plasma Na+ concentrations (P < .03). Both plasma K+ and Ca++ concentrations were lower (P < .05) among all treatment groups 1 h post-dosage but returned to initial values by 5 h and 3 h posttreatment, respectively, with no differences (P >.05) among treatments. All NaHCO3 dosages increased blood buffering capacity as indicated by increased blood pH, HCO3− concentration and BE. Maximum blood pH, HCO−3 concentration and BE was reached using a dosage of 300 mg NaHCO3/kg BW. Also, all treatments altered the plasma electrolyte concentrations. 相似文献
90.
This article covers the major pathways involved in acute inflammation in mammals with a particular emphasis on their relevance to the bovine species. It focuses on the potential and proven contributions of these systems to pulmonary defense mechanisms and lung pathology. The article also points out what is known and where gaps in our information exist as well as promising areas for research in the coming years. 相似文献