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排序方式: 共有182条查询结果,搜索用时 15 毫秒
31.
Norio KANSAKU Aya SOMA Satoko FURUKAWA Gen HIYAMA Hisato OKABAYASHII Daniel GUÉMENÉ Urs KÜHNLEIN David ZADWORNY 《Animal Science Journal》2008,79(2):163-170
The duck growth hormone encoding gene and its promoter region were amplified by polymerase chain reaction (PCR). A total of 5.25 kb were cloned and sequenced. Duck growth hormone (GH) consists of five exons and four introns and is structurally similar to mammalian and chicken GH gene. Although the distal region of duck GH promoter showed no similarity to chicken and turkey promoters, the proximal region of the promoter contained two putative Pit‐1 binding sequences, and showed similarity to chicken and turkey GH promoters. Genetic variation was detected at five positions of the promoter region. The results of this study indicate that the expression of duck GH is likely regulated in a similar manner to that of chicken GH via enhancer‐type cis‐acting elements and the presence of genetic variation in the duck GH gene may be applicable to marker‐assisted selection. 相似文献
32.
Cyprodinil is a representative of the new class of broad-spectrum anilinopyrimidine fungicides. The effect of cyprodinil on mycelial growth of Botryotinia fuckeliana on solid agar medium depends on the composition of the medium and on the age of the mycelium to be used for the bioassay. An in-vitro method was developed to study the sensitivity distribution to cyprodinil in two wild-type populations of B. fuckeliana from fruits of strawberry with grey mould. To validate the applicability of the method, sensitivities to cyprodinil, mepanipyrim and pyrimethanil were monitored in populations of B. fuckeliana from grapes with grey mould from different vineyards, including one trial vineyard where reduced performance of cyprodinil had been encountered. The monitoring procedure was based on the inhibition of the mycelial growth on a synthetic medium containing L -asparagine (asp-agar) amended with the active ingredients. The mycelium was grown on asp-agar discs, starting from a spore suspension, for 17 h prior to the beginning of the test. This procedure proved to be efficient. The two wild-type populations from different sampling sites showed similar distributions of the sensitivity to cyprodinil. Some isolates from the trial site with reduced performance of anilinopyrimidines showed reduced sensitivities to cyprodinil, mepanipyrim and pyrimethanil, demonstrating cross-resistance between these anilinopyrimidines. 相似文献
33.
Hans-Peter Rusterholz Sylvain Ursenbacher Armin Coray Urs Weibel Bruno Baur 《Journal of insect science (Online)》2015,15(1)
The sampling of living insects should be avoided in highly endangered species when the sampling would further increase the risk of population extinction. Nonlethal sampling (wing clips or leg removals) can be an alternative to obtain DNA of individuals for population genetic studies. However, nonlethal sampling may not be possible for all insect species. We examined whether remnants of traffic-killed specimens of the endangered and protected flighless longhorn beetle Iberodorcadion fuliginator (L., 1758) can be used as a resource for population genetic analyses. Using insect fragments of traffic-killed specimens collected over 15 yr, we determined the most efficient DNA extraction method in relation to the state of the specimens (crushed, fragment, or intact), preservation (dried, airtight, or in ethanol), storage duration, and weight of the sample by assessing the quantity and quality of genomic DNA. A modified cetyltrimethyl ammonium bromide method provided the highest recovery rate of genomic DNA and the largest yield and highest quality of DNA. We further used traffic-killed specimens to evaluate two DNA amplification techniques (quantitative polymerase chain reaction [qPCR] and microsatellites). Both qPCR and microsatellites revealed successful DNA amplification in all degraded specimens or beetle fragments examined. However, relative qPCR concentration and peak height of microsatellites were affected by the state of specimen and storage duration but not by specimen weight. Our investigation demonstrates that degraded remnants of traffic-killed beetle specimens can serve as a source of high-quality genomic DNA, which allows to address conservation genetic issues. 相似文献
34.
Daub Matthias Hakl Ulrike Molendijk Leendert PG Schomaker Corrie Been Thomas H van Beers Thea G Jivishova Sevda Jivishov Emil Keusgen Michael Bluemel Roman Fischer Daniel Grundler Florian MW Reuther Marie Cappel Sabrina Bauer Harald Lang Christian Watrin Cliff den Nijs Loes JMF Van Bruggen Anne-Sophie Karssen Gerrit Kiewnick Sebastian Büchler Urs Roth Irma Frey Jürg 《植物病害和植物保护杂志》2015,122(4):189-193
Journal of Plant Diseases and Protection - 相似文献
35.
Alternative poultry production with special reference to free range broilers has increased significantly since the nineties
in many regions of the world. Numerous factors influence the productive performance of this type of broilers: genotype (namely
the use of naked neck animals), feeding and access to an outdoor area. The aim of this paper is to study the influence of
each of these factors on the productive performance of free range broilers under commercial rearing conditions. A total of
3200, day old chicks of both sexes from naked neck and normally feathered genotypes were used in this trial. After a joint
initiation phase, animals were divided into four different treatments with the combination of two concentrates (high vs low
energy content) and management (access to outside park or not). Experiment lasted a total of 12 weeks. Live weight date was
recorded weekly and a samples of animals from the trial were sacrificed at the age of 8, 10 and 12 weeks, when carcass characteristics
were determined. Besides sex, the only factor that seems to affect growth characteristics was genotype as naked neck animals
had poorer growth rates than normally feathered. No effect was detected on carcass yields and percentages of carcass components
for any of the variables. From the data presented in this trial the practises associated with free range production are of
relative inconsequence to the technical animal production parameters and can only be justified by a pressing need to differentiate
these products from standard poultry products in what concerns both welfare issues and meat characteristics. The results also
indicate that genetic material from alternative poultry production in Europe can be a useful option in poultry production
development projects in the tropics. 相似文献
36.
Rebecca J. Kessler Jessica Reese Denise Chang Mayank Seth Anne S. Hale Urs Giger 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2010,39(3):306-316
Background: Testing for canine blood types other than dog erythrocyte antigen 1.1 (DEA 1.1) is controversial and complicated by reagent availability and methodology. Objectives: The objectives of this study were to use available gel column technology to develop an extended blood‐typing method using polyclonal reagents for DEA 1.1, 1.2, 3, 4, 7, and Dal and to assess the use of gel columns for cross‐matching. Methods: Dogs (43–75) were typed for DEA 1.1, 1.2, 3, 4, 7, and Dal. Methods included tube agglutination (Tube) using polyclonal reagents, a commercially available DEA 1.1 gel column test kit (Standard‐Gel) using monoclonal reagent, and multiple gel columns (Extended‐Gel) using polyclonal reagents. Blood from 10 recipient and 15 donor dogs was typed as described above and cross‐matched using the gel column technique. Results: Of 43 dogs typed for DEA 1.1, 23, 25, and 20 dogs were positive using Standard‐Gel, Extended‐Gel, and Tube, respectively. Typing for DEA 1.2 was not achievable with Extended‐Gel. For 75 dogs typed for DEA 3, 4, and 7, concordance of Extended‐Gel with Tube was 94.7%, 100%, and 84%, respectively. Dal, determined only by Extended‐Gel, was positive for all dogs. Post‐transfusion major cross‐matches were incompatible in 10 of 14 pairings, but none were associated with demonstrable blood type incompatibilities. Conclusions: Gel column methodology can be adapted for use with polyclonal reagents for detecting DEA 1.1, 3, 4, 7, and Dal. Agglutination reactions are similar between Extended‐Gel and Tube, but are more easily interpreted with Extended‐Gel. When using gel columns for cross‐matching, incompatible blood cross‐matches can be detected following sensitization by transfusion, although in this study incompatibilities associated with any tested DEA or Dal antigens were not found. 相似文献
37.
Rebecca J. Kessler Shelley Rankin Sheri Young Kathleen O'Shea Maria Calabrese Amy Guldin Nicole Lipson Donna A. Oakley Urs Giger 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2010,39(1):29-38
Background: While screening programs have reduced the risk of infectious disease transmission by donors in human and veterinary blood banking, bacterial contamination of blood products has emerged as a major complication in human medicine. Objectives: To describe a Pseudomonas fluorescens (Pf)‐contaminated feline packed RBC (pRBC) unit and experimentally investigate Pf‐contaminated canine pRBCs. Methods: Canine pRBCs were inoculated with Pf‐rich pRBCs from the sentinel feline unit and stored at 4°C or 20°C for 72 hours. Aliquots from the pRBCs were serially evaluated by microscopy, culture, and a eubacterial 16S rRNA real‐time PCR assay. Results: One Pf‐contaminated feline unit turned black after 22 days of storage and was removed from the blood bank; a source was not found, and no other contaminated units were identified. Canine pRBCs spiked with 5 or 25 μL of the sentinel unit became culture‐ and/or 16S PCR‐positive at ≥8 hours at 20°C and 48 hours at 4°C and developed a color change at ≥24 hours. Sensitivity studies indicated that without incubation, inoculation of ≥100 μL Pf‐rich pRBCs was necessary for a positive 16S PCR test result. Conclusions: P. fluorescens grows in stored pRBCs slowly at 4°C and rapidly at 20°C. Screening of blood products for color change, estimating bacterial concentration with microscopy, and 16S PCR testing are simple and fast ways to detect bacteria in stored blood. Aseptic collection, temperature‐controlled storage, and regular visual monitoring of stored units is recommended. Discolored units should not be transfused, but examined for bacterial contamination or other blood product quality problems. 相似文献
38.
Since 1993, Rhizoctonia crown and root rot (Rhizoctonia solani AG 2–2 IIIB) has represented an increasing problem for sugar beet production in Germany. Up to now, the outbreak of the infection and the spread of the disease within a field cannot be predicted and effective countermeasures are not available. Although little is known about the living conditions of R. solani in soils, abiotic soil properties are likely to influence the disease occurrence. Investigations were carried out based on 60 pairwise comparisons, each consisting of a disease‐affected and an adjacent nonaffected patch on farmers' fields in 2002 and 2003. Soil samples from the top soil layer (0–30 cm) were collected before harvest, and eight of the most frequently mentioned soil properties potentially influencing Rhizoctonia crown and root rot infection were examined: bulk density, texture, carbonate carbon, potassium, phosphorus, organic carbon, total nitrogen, and pH. The occurrence of the disease was significantly related to the soil C : N ratio, indicating the influence of soil organic matter on the disease occurrence. Examinations of soil thin sections showed that organic‐matter particles in the soil serve as a substrate for R. solani. All other soil physical and chemical properties examined did not differ between the disease‐affected and nonaffected patches and seem to be of minor importance. 相似文献
39.
The plant‐available soil water, amount and distribution of rainfall or irrigation are primary factors that may affect yield and quality of winter wheat in heterogeneous fields. The objective of this 2‐y study was to vary N application and water supply in order to achieve a more mechanistic insight into the effects of underlying differences in the site‐specific productivity on heterogeneous fields. Two N fertilizer rates (120 and 180 kg N ha–1) and three different water supply treatments (rain sheltering, irrigation, rain‐fed) were compared on field sites with lower or higher plant available soil water capacities. On the whole, the site, rather than rainfall or N fertilisation, was the primary factor that accounted for variability in grain yield. Rainfall distribution during the growing season affected the overall yield level in a given year. The sites characterised by lower plant available water capacity did not show higher grain yield and improved quality with the increased N rate. This suggests that the reduced N rate should be recommended on these sites to take into account the environmental sustainability of N fertilisation. With respect to the higher N application at sites of high plant available soil water capacity, although the already high yield levels were not increased further, the protein quality was significantly improved in the first season within all treatments and in the second season in the irrigated treatments. Therefore, a higher N‐rate proved to be advantageous, especially considering that the residual nitrate levels after harvest were low. The study demonstrated that the response of winter wheat to water shortage or abundance and N fertilisation is site‐specific and dependent on the availability of soil water. 相似文献
40.
First morphological characterization of 'Candidatus Mycoplasma turicensis' using electron microscopy
Willi B Museux K Novacco M Schraner EM Wild P Groebel K Ziegler U Wolf-Jäckel GA Kessler Y Geret C Tasker S Lutz H Hofmann-Lehmann R 《Veterinary microbiology》2011,149(3-4):367-373
At least three haemotropic mycoplasmas have been recognized in cats: Mycoplasma haemofelis (Mhf), 'Candidatus Mycoplasma haemominutum' (CMhm) and 'Candidatus M. turicensis' (CMt). The latter was originally identified in a Swiss pet cat with haemolytic anaemia and shown to be prevalent in domestic cats and wild felids worldwide using molecular methods. So far, there has been no confirmatory morphological evidence of the existence of CMt presumably due to low blood loads during infection while CMhm has only been characterized by light microscopy with discrepant results. This study aimed to provide for the first time electron microscopic characteristics of CMt and CMhm and to compare them to Mhf. Blood samples from cats experimentally infected with CMt, CMhm and Mhf were used to determine copy numbers in blood by real-time PCR and for transmission and scanning electron microscopy. High resolution scanning electron microscopy revealed CMt and CMhm to be discoid-shaped organisms of 0.3 μm in diameter attached to red blood cells (RBCs). In transmission electron microscopy of CMt, an oval organism of about 0.25 μm with several intracellular electron dense structures was identified close to the surface of a RBC. CMhm and CMt exhibited similar morphology to Mhf but had a smaller diameter. This is the first study to provide morphological evidence of CMt thereby confirming its status as a distinct haemoplasma species, and to present electron microscopic features of CMhm. 相似文献