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71.
Herbicides are typically used as the primary method of weed control. Since common reed (Phragmites australis subsp. australis) infestations in terms of density are relatively large in the State of Nebraska, USA, determining the most appropriate timing of herbicide application is critical for developing a weed management programme. Therefore, several field studies were conducted in 2007 and 2008 at three locations along the Platte River, Nebraska, with the aim of assessing the effect of herbicide selection and timing of application on common reed control. Three herbicides (glyphosate, imazapyr, and imazamox) were applied either alone at two doses or as two-way mixtures on three growth stages of common reed, including vegetative, flowering, and seed filling stages. Both doses of imazapyr (280 and 560 g active ingredient [a] ha?1) provided the highest level of control (≥ 92%) across all three timings, while imazamox provided the lowest level of control. For example, imazamox applied alone at 280 and 560 g a ha?1 provided poor control (≤ 60%) across all three timings at the highest rating date. Imazapyr and glyphosate provided the highest levels of control (90%) by the end of the first growing season and into the next growing season (390 to 450 days after treatment, DAT), regardless of the herbicide application time. Imazamox and glyphosate provided the lowest level of control (< 30%) at the first application time at 450 DAT, but slightly improved control with later timings (74% and 85% control at the flowering and seed filling stages, respectively). Stem density decreased in all herbicide applications and timings except for imazamox at both doses during the vegetative growth stage, which was not significantly different than the untreated control. 相似文献
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S. J. Kleinschuster H. J. Rapp J. Bier K. R. van Kampen R. S. Spendlove A. V. Johnston Y. Elsner 《Veterinary research communications》1979,3(1):65-71
A method is reported for the continuous in vitro culture of epithelial cells derived from bovine ocular squamous cell carcinoma. 相似文献
74.
This paper describes a primary extraskeletal osteogenic sarcoma arising in the spleen of an 11-year-old, male, cross-bred Terrier. Initial diagnosis was made after surgical removal of a splenic mass, at which time the liver and other abdominal viscera appeared grossly normal. However, elevations in the activities of alanine aminotransferase and alkaline phosphatase in blood taken 7 days after laparotomy suggested that hepatic metastases were developing. This was confirmed when the dog died 3.5 months after surgery, with massive hepatic metastatic involvement. There appears to be no previous report of the spleen being the primary site of such a neoplasm in the dog. 相似文献
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76.
Sacral osteochondrosis in two German Shepherd Dogs 总被引:1,自引:1,他引:0
KR Mathis M Havlicek JB Beck RD Eaton-Wells FM Park 《Australian veterinary journal》2009,87(6):249-252
Two young adult male castrated German Shepherd Dogs were referred for evaluation of intermittent episodes of hindlimb pain. Physical examination suggested lumbosacral stenosis, and plain radiographs and computed tomography revealed lesions consistent with sacral osteochondrosis. One dog had osteochondral fragments removed surgically; the other was managed conservatively. The surgically treated dog had complete resolution of clinical signs whereas the dog managed conservatively had repeated episodes of mild pain and received one short course of non-steroidal anti-inflammatory medication in 18 months. Sacral osteochondrosis has not been previously reported in Australia. 相似文献
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Pfeiffer E Hildebrand AA Becker C Schnattinger C Baumann S Rapp A Goesmann H Syldatk C Metzler M 《Journal of agricultural and food chemistry》2010,58(22):12055-12062
The mycotoxin zearalenone (ZEN) is produced by various Fusarium fungi and frequently found as a contaminant in food and feed. There are reports in the literature that several closely related analogues of ZEN are also formed in cultures of Fusarium species. We have therefore analyzed the organic extract from a 40 day culture of Fusarium graminearum by LC-DAD-MS and detected 15 compounds, which could be congeners of ZEN because of their ultraviolet, mass spectroscopy, and tandem mass spectroscopy spectra. In addition to confirming the previously reported α- and β-stereoisomers of 5-hydroxy-ZEN and 10-hydroxy-ZEN, we identified seven ZEN congeners for the first time. One of the major novel congeners was shown by nuclear magnetic resonance spectroscopy and chemical synthesis to have the structure of an aliphatic ZEN epoxide, whereas two minor products proved to be the corresponding dihydrodiols. In addition, three stereoisomers of a cyclization product of the dihydrodiols, carrying a spiro-acetal group, were identified as fungal products for the first time. The latter may be artifacts, because the ZEN epoxide and dihydrodiol are unstable under acidic conditions and rearrange easily to the spiro-acetal compounds. 相似文献
79.
Isolation and pathogenicity of Australian strains of Eimeria praecox and Eimeria mitis 总被引:2,自引:0,他引:2
WK JORGENSEN NP STEWART PJ JESTON JB MOLLOY GW BLIGHT RJ DALGLIESH 《Australian veterinary journal》1997,75(8):592-595
Objective To determine the presence of E praecox and E mitis in Australia, to isolate representative strains of these species from chickens and determine their pathogenicity.
Design Morphological, physiological and cross protection studies were undertaken to confirm the identity of Australian isolates of E praecox and E mitis.
Procedure Oocysts were isolated from a backyard flock at Jimboomba, southeastern Queensland and numbers of E praecox and E mitis enriched by passage in chickens immune to five other species of poultry Eimeria . Oocysts of mean conformation and size of the two species were purified by single oocyst passage. Two isolates that closely matched recorded parameters for E praecox and E mitis were selected and designated JP and JM respectively. The cross protection between the isolates and E acervulina was determined by infection and challenge experiments. The virulence of the two isolates was determined by comparing weight gains of groups of birds inoculated with JP isolate or JM isolate with untreated groups.
Results Isolates JP and JM most closely matched recorded parameters of E praecox and E mitis respectively. Groups of chickens, previously infected with JP and JM isolates, showed no significant protection against infection with E acervulina . In a separate trial, groups of susceptible chickens inoculated with 105 oocysts of JP and JM isolates showed significantly reduced weight gains compared with untreated controls.
Conclusion Isolates JP and JM are E praecox and E mitis respectively, confirming the presence of these species in Australia. These isolates were found capable of causing significant reductions in weight gains in susceptible chickens. 相似文献
Design Morphological, physiological and cross protection studies were undertaken to confirm the identity of Australian isolates of E praecox and E mitis.
Procedure Oocysts were isolated from a backyard flock at Jimboomba, southeastern Queensland and numbers of E praecox and E mitis enriched by passage in chickens immune to five other species of poultry Eimeria . Oocysts of mean conformation and size of the two species were purified by single oocyst passage. Two isolates that closely matched recorded parameters for E praecox and E mitis were selected and designated JP and JM respectively. The cross protection between the isolates and E acervulina was determined by infection and challenge experiments. The virulence of the two isolates was determined by comparing weight gains of groups of birds inoculated with JP isolate or JM isolate with untreated groups.
Results Isolates JP and JM most closely matched recorded parameters of E praecox and E mitis respectively. Groups of chickens, previously infected with JP and JM isolates, showed no significant protection against infection with E acervulina . In a separate trial, groups of susceptible chickens inoculated with 10
Conclusion Isolates JP and JM are E praecox and E mitis respectively, confirming the presence of these species in Australia. These isolates were found capable of causing significant reductions in weight gains in susceptible chickens. 相似文献
80.