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101.
This study presents the development of a core collection capturing the genetic diversity of a collection of 350 tetraploid cultivated potato varieties (Solanum tuberosum L.). The core collection was established by using simple sequence repeats (SSR) data and the M strategy, which aims at maximizing the allelic diversity. A 48-core collection was defined which captured 99.5% of the SSR alleles used to establish it, and 96.9% of the SSR alleles which belonged to an independent set of markers. The defined core collection was further validated by analysing 35 agro-morphological traits. The class coverage value and the estimates of the Shannon-Weaver diversity index indicated a good representation of the phenotypic diversity in the core collection. Furthermore, the core set included accessions having the most desirable status for several agronomic traits. A linkage disequilibrium (LD) analysis, using data obtained with the SolCAP SNP array on the defined core collection, was performed. The population structure analysis showed that the core collection did not present a clear genetic structure. The linkage disequilibrium analysis carried out between markers located on the same pseudomolecule within 10,000 bp concluded that 41.3% of these pairs of SNP markers have a significant LD. We conclude that this core collection, representative of the genetic diversity of cultivated potato varieties, is a relevant tool for a first screening for genetic variation regarding novel traits of interest.  相似文献   
102.
Active surveillance of bats in France started in 2004 with an analysis of 18 of the 45 bat species reported in Europe. Rabies antibodies were detected in six indigenous species, mainly in Eptesicus serotinus and Myotis myotis, suggesting previous contact with the EBLV-1 rabies virus. Nineteen of the 177 tested bats were shown serologically positive in seven sites, particularly in central and south-western France. Neither infectious viral particles nor viral genomes were detected in 173 and 308 tested oral swabs, respectively. The presence of neutralising antibodies in female bats (18.6%) was significantly higher than in males (5.6%).  相似文献   
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105.
Bixin, also known as annatto, is a seed-specific pigment widely used in foods and cosmetics since pre-Columbian times. We show that three genes from Bixa orellana, native to tropical America, govern bixin biosynthesis. These genes code for lycopene cleavage dioxygenase, bixin aldehyde dehydrogenase, and norbixin carboxyl methyltransferase, which catalyze the sequential conversion of lycopene into bixin. Introduction of these three genes in Escherichia coli engineered to produce lycopene induced bixin synthesis, thus expanding the supply of this economically important plant product.  相似文献   
106.
107.
The higher fatty acids (HFA) are important plant constituents that are implicated in the grass tetany hazard in livestock. A method is given whereby a technician can analyze 12 forage samples daily for HFA content.

The method consists of saponifying the plant material in ethanol and KOH and extracting the subsequently acidified HFA with petroleum ether. The petroleum ether phase is evaporated and the HFA residue is dissolved in ethanol and then titrated with standardized isobutanolic KOH in the absence of O2 by using a N2 atmosphere. A standard plant sample, analyzed over a 37‐day period, had a mean of 136 mmol H+ /kg ±4.5, where a 0.1 mmol H+ / l palmitic standard was determined with an accuracy of 99 ± 1.9%.  相似文献   
108.
Three plant products with known insecticidal properties, a dry extract of flowers ofChrysanthemum cinerariaefolium (Trevir.) Vis. produced in Rwanda, an ethanol extract of seeds of neem,Azadirachta indica A. Juss., and crushed leaves ofTetradenia riparia Hochst Codd., a traditional Rwandan medicine, were mixed with beans,Phaseolus vulgaris L., for storage protection. These plant-protected beans were compared with off the shelf beans that were being sold to consumers by the Rwandan National Agricultural Products Marketing Organization (OPROVIA). A trained sensory panel determined that beans treated with neem andC. cinerariaefolium were as acceptable after 8 months storage as those being sold throughout Rwanda by the marketing organization. Beans marketed by this organization were all treated with the standard insecticide application in Rwanda, 0.01% weight/weight pirimiphos methyl in a powder formulation. Instrumental hardness (% hard-to-cook/mean gram force) after 20 months of storage was acceptable for beans stored with neem or withC. cinerariaefolium or with the conventional government application of pirimiphos methyl. Use of either neem orC. cinerariaefolium for storage protection should not affect consumer acceptance of dry beans.  相似文献   
109.

Purpose

The authors studied the role of bacteria belonging to Anaplasmataceae family as the causes of acute illnesses of sheep in West Africa.

Methods

We examined and sampled 120 febrile sheep in two regions of Senegal for this study. The DNA extracted from these blood samples was tested by PCR using two pairs of primers (groEL-based and 16S rRNA gene-based).

Results

In 52/120 samples, the microscopic examination revealed intraerythrocytic and/or intraphagocytic spherical inclusions. In 48/52 cases, we succeeded in identifying the bacterial agent: in 38 cases, it was Anaplasma ovis; in six cases, it was Ehrlichia ruminantium; in two cases, Anaplasma phagocytophilum; in one case, Anaplasma platys; and in one case, a yet uncultured Anaplasma sp. closely related to A. phagocytophilum.

Conclusions

Our studies demonstrated the great variety of pathogenic bacteria from the Anaplasmataceae family in the blood of clinically ill sheep. A. ovis was identified unexpectedly often. For the first time, A. phagocytophilum was found in sub-Saharan Africa, and its further epidemiology may be now reconsidered. The roles of canine pathogen, A. platys, and yet undescribed Anaplasma sp. “Badiouré” in ovine pathology should be more closely studied.  相似文献   
110.
The purpose of this paper by the Regulatory Affairs Committee (RAC) of the American Society for Veterinary Clinical Pathology (ASVCP) is to review the current regulatory guidances (eg, guidelines) and published recommendations for best practices in veterinary toxicologic clinical pathology, particularly in the pharmaceutical and biotechnology industries, and to utilize the combined experience of ASVCP RAC to provide updated recommendations. Discussion points include (1) instrumentation, validation, and sample collection, (2) routine laboratory variables, (3) cytologic laboratory variables, (4) data interpretation and reporting (including peer review, reference intervals and statistics), and (5) roles and responsibilities of clinical pathologists and laboratory personnel. Revision and improvement of current practices should be in alignment with evolving regulatory guidance documents, new technology, and expanding understanding and utility of clinical pathology. These recommendations provide a contemporary guide for the refinement of veterinary toxicologic clinical pathology best practices.  相似文献   
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