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101.
Meyer H 《DTW. Deutsche tier?rztliche Wochenschrift》2001,108(1):26-30
During the 19th century in Germany mainly veterinarians working at agricultural schools or appointed to veterinary schools from there (for example HAUBNER, ROLOFF, DAMMANN, ALBRECHT, KRONACHER) made considerable contributions to the development of animal nutrition. They disseminated knowledge of feedstuffs and feeding techniques to the interested public at large by books concerning animal husbandry and especially "Gesundheitspflege" (health regimen; Tab. 1). Their experimental work (Tab. 2) extended from digestibility of feedstuffs, Ca-, P- and rumen metabolism (NPN), respectively, to feed intoxications. The interest in preventive measures being stronger at school of agriculture than at veterinary schools probably stimulated this development. 相似文献
102.
103.
Belloy L Giacometti M Abdo EM Nicolet J Krawinkler M Janovsky M Bruderer U Frey J 《Veterinary research》2001,32(2):155-164
The serological cross reactions between Mycoplasma conjunctivae, the etiological agent of infectious keratoconjunctivitis (IKC), and the antigenetically and phylogenetically closely related Mycoplasma ovipneumoniae, which is often found in sheep, were analysed. Cross reacting antigens were identified using sera from sheep with IKC and from sheep of herds known to be free of IKC, as well as rabbit hyperimmune serum specific to the two Mycoplasma species. Cross reactions were predominantly due to the strongly antigenic proteins of 42 kDa and 83 kDa. Serospecific antigens of M. conjunctivae could be separated from cross-reacting antigens by the extraction of Tween 20-soluble membrane proteins. The Tween 20-extracted proteins of the M. conjunctivae strain HRC/581T were used for the development of an indirect ELISA test. This ELISA test was shown to be a useful serological method for the diagnosis of M. conjunctivae infections and to identify infected sheep herds. 相似文献
104.
C. Kubo E. Nakazono-Nagaoka K. Hagiwara H. Kajihara S. Takeuchi K. Matsuo T. U. Ichiki T. Omura † 《Plant pathology》2005,54(5):615-620
New strains of Melon necrotic spot virus (MNSV), designated MNSV-YS and MNSV-KS, caused much more severe growth retardation on melon plants than MNSV-NH, which was previously reported as the most severe strain of MNSV in Japan. MNSV-YS spread much more quickly than MNSV-NH in infected plants, and induced more severe growth retardation, even though the appearance of necrotic lesions on inoculated cotyledons was much slower. MNSV-KS had properties intermediate between those of the other two strains. The results suggest that faster-spreading strains can multiply more rapidly as a result of lower levels of activity in inducing necrotic lesions in melon plants. The complete sequences of MNSV-YS and MNSV-KS were determined, and an RT–PCR–RFLP method based on these sequences was successfully developed to detect and discriminate between the three strains. 相似文献
105.
106.
The effect of Agrostemma githago L. and other naturally occurring weeds on biomass production and grain yield was studied in winter wheat and winter barley. Naturally occurring weeds had only a negligible effect on barley, but reduced wheat grain yield by 10% at a quarter of normal crop density. The interaction between the cereals and A. githago was studied in additive series employing different crop densities. Growth of this weed species was strongly dependent on crop density, which was more important for controlling weed growth than it was for obtaining a normal grain yield. Wheat and especially barley had a better competitive ability than A. githago. Wheat and A. githago utilized resources for growth better when grown in mixture than when grown in pure stands as the relative yield totals were significantly larger than unity. 相似文献
107.
Detection of the German grapevine yellows (Vergilbungskrankheit) MLO in grapevine,alternative hosts and a vector by a specific PCR procedure 总被引:5,自引:0,他引:5
M. Maixner U. Ahrens E. Seemüller 《European journal of plant pathology / European Foundation for Plant Pathology》1995,101(3):241-250
A polymerase chain reaction procedure was developed which enables specific amplification of a ribosomal sequence from the mycoplasmalike organism (MLO) associated with German grapevine yellows (Vergilbungskrankheit, VK) and stolbur-related diseases of solanaceous plants. Successful amplification from all samples prepared from various cultivars collected in different viticultural areas indicates that the causal agent is a relatively homogeneous organism. Amplification was also achieved with template DNA prepared from naturally infected weeds in vineyards such asConvolvolus arvensis andSolanum nigrum, and from the planthopperHyalesthes obsoletus that was collected in the vineyards. Feeding of insects of this species on grapevine seedlings resulted in the development of typical yellows symptoms by the grapes.H. obsoletus could therefore be identified as a vector of Vergilbungskrankheit.Abbreviations FD
Flavescence dorée
- GY
Grapevine yellows
- MLO
Mycoplasmalike organism
- PCR
Polymerase chain reaction
- RFLP
restriction fragment length polymorphism
- VK
Vergilbungskrankheit (German grapevine yellows) 相似文献
108.
Fellström C Karlsson M Pettersson B Zimmerman U Gunnarsson A Aspan A 《Veterinary microbiology》1999,70(3-4):225-238
Two type/reference strains of Brachyspira (B.) hyodysenteriae, 14 Belgian and German indole negative, and 14 Belgian, German and Swedish indole positive field isolates of strongly β-haemolytic intestinal spirochaetes were compared by pulsed-field gel electrophoresis (PFGE) patterns, biochemical reaction patterns, 16S rDNA sequences and MIC determinations of six antibacterial substances. Three tests for indole production, including a spot indole test, were compared with congruent results. All field isolates were classified as B. hyodysenteriae due to a high genetic and phenotypic similarity with the type strains. The Belgian and German indole negative isolates had identical and unique PFGE patterns for the tested restriction enzymes MluI and SalI, as well as identical 16S rDNA sequences, and they could not be differentiated by any of the methods used. Seven unique PFGE patterns were achieved from the 14 indole positive field isolates. The patterns were identical and unique for epidemiologically related isolates. Type/reference strains and isolates without known relation to other tested isolates showed unique banding patterns. The MICs of tylosin, tiamulin, erythromycin, clindamycin, carbadox and virginiamycin were determined in broth for all isolates. In contrast to Belgian and German isolates, the majority of the Swedish field isolates were susceptible to tylosin, erythromycin and clindamycin. Probable pathways of infection for some of the Swedish isolates were determined. The PFGE patterns of epidemic clones of B. hyodysenteriae remained stable for a period of up to 8 years. In vivo development of resistance to macrolide and lincosamide antibiotics due to use of tylosin was clearly indicated for two epidemic clones. 相似文献
109.
Wernery U Zachariah R 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1999,46(2):131-135
Four dromedaries were infected with a virulent camelpox virus strain which was isolated from the lung of a Saudi Arabian camel. The camels which were infected intradermally and subcutaneously developed severe generalized camelpox. One of these camels had to be euthanized on humane grounds and the second one died 13 days after being infected. This dromedary also developed internal pox. Neither dromedary showed camelpox antibodies before infection. The other two camels which had been vaccinated with Ducapox 6 years prior to the viral challenge did not develop any clinical symptoms when given 5 ml of the field virus intravenously and intramuscularly. They seroconverted after the challenge. Although only two camels were used for this trial, the results indicate that a single dose of Ducapox can protect 1-year-old camels from camelpox infection for several years. 相似文献
110.