Evaluation of mosquitoes, Aedes vexans, as biological vectors of porcine reproductive and respiratory syndrome virus   总被引：1，自引：0，他引：1       下载免费PDF全文

Satoshi Otake  Scott A. Dee  Roger D. Moon  Kurt D. Rossow  Carlos Trincado    Carlos Pijoan 《Canadian journal of veterinary research》2003,67(4):265-270

The objective of this study was to determine whether mosquitoes, Aedes vexans (Meigen), could serve as biological vectors of porcine reproductive and respiratory syndrome virus (PRRSV). Specifically, the study assessed the duration of viability and the site of PRRSV within mosquitoes, and evaluated whether PRRSV could be transmitted to a susceptible pig by mosquitoes following a 7- to 14-day incubation period after feeding on an infected pig. For the first experiment, a total of 100 mosquitoes were allowed to feed on a pig, experimentally infected with PRRSV (day 7 post-inoculation) and were then maintained alive under laboratory conditions. A set of 10 mosquitoes were collected at 0 hour (h), 6 h, 12 h, 24 h, 48 h, 72 h, 5 days (d), 7 d, 10 d, and 14 d post-feeding (pf). Samples of exterior surface washes, salivary glands, thorax carcasses, and gut homogenates were collected from each set of mosquitoes, and tested for PRRSV. Infectious PRRSV was detected by polymerase chain reaction and swine bioassay only from the gut homogenates of mosquitoes collected at 0 h and 6 h pf. For the second experiment, a total of 30 mosquitoes were allowed to feed on a pig, experimentally infected with PRRSV and the mosquitoes were then maintained under laboratory conditions. On each of day 7, 10, and 14 pf, a set of 10 mosquitoes were allowed to feed on a susceptible pig. Transmission of PRRSV to susceptible pigs did not occur, and PRRSV was not detected from the mosquitoes. These findings indicate that mosquitoes are not likely to serve as biological vectors of PRRSV.  相似文献   

Efficacy of ivermectin administered via sustained-release bolus against gastrointestinal nematodes in cattle   总被引：1，自引：0，他引：1  

G L Zimmerman  D M Mulrooney  D H Wallace 《American journal of veterinary research》1991,52(1):62-63

Twelve calves (mean weight, 175.5 kg) were used to confirm efficacy of ivermectin delivered from a prototype sustained-release bolus against naturally acquired gastrointestinal nematodes including early fourth-stage (inhibited) larvae of Ostertagia ostertagi. The calves were allocated by restricted randomization on weight to 1 of 2 groups: controls, to which a placebo bolus was given orally, and treated calves, to which a sustained-release bolus designed to deliver 8 mg of ivermectin/day at a steady rate was given orally. After treatment, the 2 groups were housed in separate pens with concrete flooring. Twenty-eight days after treatment, all calves were euthanatized and necropsied. The ivermectin-treated calves had no larval or adult Ostertagia spp and significantly (P less than 0.01) fewer adult Trichostrongylus axei and adult Cooperia (C oncophora, C punctata and C surnabada) than control calves. Efficacy of ivermectin was greater than 99% for Cooperia spp, and 100% for other parasites. Drug-related adverse reactions were not observed.  相似文献   

Das neue Reichsgesetz gegen waldverwüstung und sein Dollzug in den deutschen Ländern     

Dr. Kurt Mantel 《European Journal of Forest Research》1934,56(18):597-615

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Anthelmintic efficacies of fenbendazole, ivermectin, and levamisole against Nematodirus battus infections in lambs     

G L Zimmerman  E P Hoberg  L G Rickard  J K Bishop 《American journal of veterinary research》1988,49(12):2094-2095

Anthelmintic efficacies of fenbendazole, ivermectin, and levamisole were evaluated against naturally acquired infections of Nematodirus battus in lambs. Four groups of 10 lambs each were used. Oral administration of 8 mg of levamisole/kg of body weight or 5 mg of fenbendazole/kg significantly (P less than 0.01) reduced the degree of infection by N battus (adults) by greater than 99%. An oral formulation of 200 micrograms of ivermectin/kg was 98% effective (P less than 0.01). Numbers of other Nematodirus spp (including N filicollis and N spathiger) were significantly reduced.  相似文献   

Der Nitratgehalt von Gemüsen in Abhängigkeit von Pflanzenart und einigen Umweltfaktoren     

Kurt Boek  Werner Schuphan 《Plant foods for human nutrition (Dordrecht, Netherlands)》1959,5(3):199-208

Zusammenfassung Zur Prüfung der für die menschliche Ernährung wichtigen Frage des in gesundheitlicher Beziehung nicht ganz unbedenklichen Nitratgehaltes von Gemüse wurden an der Bundesanstalt für Qualitätsforschung in Geisenheim/Rheingau umfangreiche Untersuchungen durchgeführt. Die Nitratbestimmungen ergaben verschieden hohe Gehalte je nach botanisch-systematischer Zugehörigkeit der einzelnen Gemüsearten. Typische Nitratspeicherer unter den häufiger genossenen Gemüsepflanzen sind der Spinat, die Rote Rübe und die Kohlarten. Die einzelnen Pflanzenorgane führten Nitrat in unter-schiedlicher Höhe.Einen entscheidenden Einfluß auf die Menge des gespeicherten Nitrats hat die Art und Höhe der Stickstoffdüngung. Verabfolgung von Jauche führte, ebenso wie Salpeterdüngung zu höheren Nitratgehalten als eine Düngung mit ammoniumhaltigen Mineraldüngern. Je höher die Stickstoffgaben waren, desto höher stieg im allgemeinen auch der Nitratgehalt des untersuchten Pflanzenmaterials. Auch die Lichtintensität erwies sich als mitbestimmender Faktor auf die Höhe des Nitratgehaltes, wie Klimakammerversuche bei abgestufter künstlicher Beleuchtung mit Spinat zeigten (hohe Licht-Intensität = niedriger, geringe L.I. = hoher Nitratgehalt). Standortversuche, ebenfalls mit Spinat, an klimatisch differenten Orten ergaben, daß die Nitratgehalte bei sonnigen warmen Witterungsbedingungen (Geisenheim/Rhein) niedrig, bei kühlen niederschlagsreichen, also lichtärmeren (Kiel), hoch waren.Mit diesem im Nitratgehalt unterschiedlichen Spinat wurden (nach Dosenkonservierung) Ernährungsversuche mit Säuglingen in der Universitätskinderklinik Kiel (Direktor: Prof. Dr. med.W. Catel) durch Dr. med.W. Kübler durchgeführt, die in seiner nachfolgenden Arbeit beschrieben werden (16).

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Summary Experiments have been carried out at the Bundesanstalt für Qualitätsforschung pflanzlicher Erzeugnisse in Geisenheim/Rhine on vegetables to determine the amount of nitrates, to be looked upon as somewhat detrimental for human health. Determinations of nitrate showed contents, different according to systematic relationships of vegetables. Those vegetables, as spinach, beet roots, cabbages and kale are typical plants storing nitrates. Plant organs differ in the amount of nitrates stored.Nitrogen-fertilizers influence the amount of accumulated nitrates depending on N-fertilizers and amount of Nitrogen. Liquid manure and nitrate supply gave rise to higher contents of nitrate as ammoniac fertilizers.The higher the amount of nitrogen, the higher raised the contents of nitrate in plant material investigated. Different light intensities, mesured in climate chambers, have been proved to be a determining factor regarding amount of nitrates in plants. High light intensity show low contents of nitrate, low one a high amount of NO₃. Environmental experiments with spinach on places, different in climatic conditions, resulted in contents of nitrates which were low when sunny warm weather conditions (Geisenheim/Rh.) prevailed and vice versa (Kiel).After canning, this spinach differing in nitrate-contents has been administered babies in nutritional trials by Dr. med.W. Kübler in the Univ. Klinik Kiel (Director Prof. Dr. med.W. Catel). The results are given in the following paper by Dr.Kübler (16).

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Mit 5 Tabellen und 2 Fig.

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Gemeinschaftsversuche der BAQ mit der Universitätskinderklinik Kiel (Direktor: Prof. Dr. med.W. Catel) vgl. auch S. 297.  相似文献   

Induced group A beta-hemolytic streptococcic infection in chimpanzees   总被引：1，自引：0，他引：1  

D H Krushak  R A Zimmerman  B L Murphy 《Journal of the American Veterinary Medical Association》1970,157(5):742-744

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Evaluation of the Krupin-Denver valve implant in normotensive and glaucomatous beagles     

K N Gelatt  G G Gum  D A Samuelson  R M Mandelkorn  K W Olander  T J Zimmerman 《Journal of the American Veterinary Medical Association》1987,191(11):1404-1409

The Krupin-Denver valve was implanted unilaterally in 2 normotensive and in 6 glaucomatous Beagles. The fellow eye of each dog had an external trabeculectomy. Before and after surgery, all dogs were evaluated serially by gonioscopy, biomicroscopy, tonometry, and tonography. The valve implant remained patent in 2 normotensive and in 2 glaucomatous Beagles throughout the 12 months of observation. Valve function was lost in 4 glaucomatous Beagles 4 to 6 weeks (3 dogs) and 6 months (1 dog) after implantation. Light microscopic and scanning electron microscopic evaluations of early loss of implant function revealed occlusion of the lumen and/or valve mechanism by inflammatory debris and cells. The late loss of valve function was related to chronic inflammatory response and fibrosis about the valve mechanism and tubing within the sclera.  相似文献   

Insecticidal isosteres of DDT-pyrethroid structures     

George Holan  Wynona M. P. Johnson  Kurt Rihs  Christopher T. Virgona 《Pest management science》1984,15(4):361-368

Several new series of insecticidally active oxime O-ethers are reported, and compared structurally and biologically with known oxime O-ether insecticides. These compounds can exist in two geometric forms. Biological results demonstrate that the configuration of the active isomer and the effect of substituents around the C-N double bond vary between series. A detailed structure-activity examination is presented.  相似文献   

Bioeconomic firm-level model of beef,forage and grain farms in Western Canada: Structure and operation     

Kurt K. Klein  Bernard H. Sonntag 《Agricultural Systems》1982,8(1):41-53

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Chimärenbildungen bei der Tomatenmutantegilva vonLycopersicon esculentum Mill. nach Behandlung von heterozygotem Samenmaterial mit Colchicin und Röntgenstrahlen     

Kurt Gröber 《Genetic Resources and Crop Evolution》1962,10(1):293-311

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