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Four methods of predicting breeding values for carcass gain are compared: “regressed” least squares (RLSQ), mixed model (MM), mixed model with relationships among sires considered (MMR) and contemporary-comparison (CC). Very small changes in the ranking of the sires were observed from one method to another (rank correlations > 0.96). Consideration of the relationships among the sires or deleting the breed-group factor from the model did not lead to substantially different breeding values. The good correspondence of the predictors is mainly due to the well balanced distribution of the progeny over herds. 相似文献
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N. Künzi C. Gaillard H. Leuenberger M. Schneeberger F. Weber 《Livestock Production Science》1978,5(3):245-252
The mating of small beef type bulls (Angus, Eringer) to reduce difficulties at first calvings is increasingly applied in Switzerland. In contrast to this, calf producers refuse to use large type beef bulls on their cows because of direct and indirect damages due to increased calving problems. It proved to be an attractive alternative to use specially selected dual purpose bulls tested for ease of calving and high growth rate but low dairy performance, so called M-bulls (Meat bulls), out of the regular AI testing programme for Braunvieh and Simmentals.From 1974 to 1976, Charolais, Limousin and Piemontese bulls were included in the AI testing programme and compared with Braunvieh- and Simmental-M-bulls. Data included progeny from 47 bulls, 7936 calvings, 1137 animals with carcass gains, and 130 dissected carcasses. If calving performance and net gains are considered, the M-bulls compete well with the foreign breeds. If, in addition, the amount of meat in the carcass is taken into account, then Charolais and Piemontese crosses are superior. The problem is one of distributing gains and losses among calf producers, feeders and butchers. It needs specially tested bulls with emphasis on ease of calving out of the specialized beef breeds or sire lines to persuade the dairy farmer to cross his cows. 相似文献
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Comparative genomics‐informed design of two LAMP assays for detection of the kiwifruit pathogen Pseudomonas syringae pv. actinidiae and discrimination of isolates belonging to the pandemic biovar 3 下载免费PDF全文
M. Ruinelli P. H. H. Schneeberger P. Ferrante A. Bühlmann M. Scortichini J. L. Vanneste B. Duffy J. F. Pothier 《Plant pathology》2017,66(1):140-149
The aim of this study was to develop a rapid, sensitive and reliable field‐based assay for detection of the quarantine pathogen Pseudomonas syringae pv. actinidiae (Psa), the causal agent of the most destructive and economically important bacterial disease of kiwifruit. A comparative genomic approach was used on the publicly available Psa genomic data to select unique target regions for the development of two loop‐mediated isothermal amplification (LAMP) assays able to detect Psa and to discriminate strains belonging to the highly virulent and globally spreading Psa biovar 3. Both LAMP assays showed specificity in accordance with their target and were able to detect reliably 125 CFU per reaction in less than 30 min. The developed assays were able to detect the presence of Psa in naturally infected kiwifruit material with and without symptoms, thus increasing the potential of the LAMP assays for phytosanitary use. 相似文献
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A diagnostic tool for improved detection of Xanthomonas fragariae using a rapid and highly specific LAMP assay designed with comparative genomics 下载免费PDF全文
M. Gétaz A. Bühlmann P. H. H. Schneeberger C. Van Malderghem B. Duffy M. Maes J. F. Pothier B. Cottyn 《Plant pathology》2017,66(7):1094-1102
Molecular diagnostics of plant pathogens are crucial to prevent disease spread and to enhance food quality and security. A comparative genomics approach using genomes of different Xanthomonas species and pathovars was applied to identify highly specific targets in the genome of Xanthomonas fragariae, the causal agent of angular leaf spot of strawberry, listed under quarantine regulations in Europe. A reliable and sensitive loop‐mediated isothermal amplification (LAMP) assay was designed using a unique marker, providing a highly specific and rapid detection technique, convenient for on‐site detection. Specificity of the designed assay was tested on 37 strains from a culture collection of X. fragariae, 82 strains of other Xanthomonas species and pathovars and 11 strains of other bacterial genera isolated from strawberry leaves. A detection limit of 102 fg was achieved, approximating to 20 genome copies per reaction. When performing analyses with crude plant material, a consistent lower detection efficiency of 102 CFU mL?1 was achieved. The LAMP assay designed in this study was adapted to work on crude plant material without any prior extensive extraction steps or incubation period; moreover, it does not require advanced analytical knowledge or a fully equipped laboratory. Results were produced within 7–20 min, depending on the pathogen concentration, thus providing a high‐throughput and user‐friendly method for detection and screening of plant material in support of quarantine regulations. 相似文献
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Ika?DarnhoferEmail author Walter? Schneeberger Bernhard?Freyer 《Agriculture and Human Values》2005,22(1):39-52
Reasons for converting to organic farming have been studied in a number of instances. However, the underlying rationale that motivates the behavior is not always made clear. This study aims to provide a detailed picture of farmers decision-making and illustrate the choice between organic and conventional farm management. Based on 21 interviews with farmers, a decision-tree highlighting the reasons and constraints involved in the decision of farmers to use, or not to use, organic production techniques was formulated. The accuracy of the decision-tree was tested through a written survey of 65 randomly sampled farmers. The decision-tree permits the identification of decision criteria and examines the decision-making process of farmers in choosing their farming method. It also allows for the characterization of farmer strategies and values, identifying five types of farmers: the committed conventional; the pragmatic conventional; the environment-conscious but not organic; the pragmatic organic; and the committed organic. The importance of taking into account heterogeneity in farmers attitudes, preferences, and goals and their impact on the choice of a farming method is emphasized.Ika Darnhofer is an Assistant Professor at the Institute of Agricultural and Forestry Economics at the University of Natural Resources and Applied Life Sciences Vienna. She received both her MSc and PhD in Agricultural Economics from the University of Natural Resources and Applied Life Sciences Vienna, working on issues of agricultural development in Africa. Her current research interests include economic and sociological analyses of factors that shape farmers land use decision-making behavior, with a particular focus on organic farming.Walter Schneeberger is a Full Professor of Farm Business Management and Head of the Institute of Agricultural and Forestry Economics at the University of Natural Resources and Applied Life Sciences Vienna. His current research interests include the economics of producing and processing agricultural products and farm business management for both conventional and organic farms.Bernhard Freyer is a Full Professor of Organic Farming and Head of the Institute of Organic Farming of the University of Natural Resources and Applied Life Sciences Vienna. His work on organic farming focuses on its agronomic aspects (plant cultivation, crop rotations, and soil fertility) as well as on the analysis of conversion to organic farming (planning process, farm development) and its potential for regional development. 相似文献
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W. H. Schroeder G. Keeler H. Kock P. Roussel D. Schneeberger F. Schaedlich 《Water, air, and soil pollution》1995,80(1-4):611-620
To determine the extent of comparability of sampling and analytical procedures for atmospheric mercury (Hg) being used by different scientific groups around the world and hence the compatibility of measurement results, the Atmospheric Environment Service (AES) co-ordinated a field intercomparison study in Windsor, Ontario, over a period of 5 days- during Sept./Oct.,1993. This study brought together 2 groups (University of Michigan Air Quality Laboratory; Chemistry Institute of GKSS) which performed conventional (manual) sample collection procedures for total gaseous mercury (TGM) and for particulate-phase mercury (PPM), followed by cold-vapor atomic fluorescence spectrophotometric (CVAFS) analysis in the respective laboratories. Two other groups (Ontario Hydro, and the Ontario Ministry of Environment & Energy) each operated a novel mercury vapor analyzer produced by Tekran Inc. of Toronto. As is the case for the manual methods, this analyzer also uses gold amalgamation and CVAFS. During the intercomparison, meteorological parameters (air temperature, barometric pressure, wind speed/direction and relative humidity) were obtained at the study site. 相似文献
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Cows were tested for milkability with standardized milking equipment. Percentage of milk from the forequarters (FQ%), average milk flow rate (AMF) in kg min?1, quantity of hand-stripped milk (HSM) and milk yield at test day (MTD) were recorded. Records of 10 823 daughters in the first lactation of 352 sires were used to investigate environmental influences and to estimate genetic parameters. Significant effects were test season and herd production level for AMF and HSM, test person, milking equipment on the farm, month in lactation, age at calving and region for FQ%, AMF and HSM. The heritabilities were 0.34 for FQ%, 0.41 for AMF and 0.10 for HSM. The genetic correlations of MTD were 0.13 with FQ%, 0.23 with AMF and ?0.20 with HSM. The genetic correlations between FQ% and AMF and all genetic correlations with HSM were negative. Selection indices with information on average deviations of daughters' MTD, FQ%, AMF and HSM from corresponding region — herd level — season means and different economic weights were used to predict selection indices for 239 sires. The predicted breeding values were compared with simple daughter averages. The correlations were high, but large differences in ranks occurred for individual sires. Correcting AMF for milk yield removes some genetic variation in milk flow and can mask genetic differences between sires. 相似文献