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71.
Archimède H Gourdine JL Fanchone A Tournebize R Bassien-Capsa M González-García E 《Tropical animal health and production》2012,44(6):1289-1296
Using a mechanistic model, we compared five alternative farming systems with the purpose of transforming monoculture (MON) banana farms into mixed farming systems (MFS) with ruminants feeding banana by-products (leaves, pseudostems and nonmarketable fruits) and forage from the fallow land. The paper presents the main structure of the model (land surface changes, available biomass for animals, stocking rates, productive or reproductive indicators), and impact assessment (change in farm productivity) is discussed. Five MFS with typical local ruminant production systems were used to compare MON to the strategies using forage from fallow and/or integrating Creole cattle (CC), Creole goats (CG) or Martinik sheep (MS) into banana farming. One hectare MON shifted into an MFS allows a stocking rate of 1,184, 285, and 418 kg of live weight per hectare for CC, CG and MS, respectively. Banana by-products seem to be better valorized by the CC scenario. However, parameters such as length of the cycle, local prices for cattle, goat and sheep meat, work time and farmer's skills in ruminant management may have been taken into account by the farmer when choosing the ruminant species to rear. 相似文献
72.
Audrey C. Muguet‐Chanoit DVM MS Ji‐Hey Lim DVM PhD Ryan Gallagher DVM Zachary Niman DVM Diplomate ACVIM Neurology Stacy Dillard DVM Diplomate ACVIM Neurology James Campbell DVM PhD Peter Early DVM Diplomate ACVIM Neurology Karen R. Muñana DVM MS Diplomate ACVIM Neurology Courtenay Freeman DVM Marc Kent DVM Diplomate ACVIM Neurology Carley Giovanella DVM Diplomate ACVIM Neurology 《Veterinary surgery : VS》2012,41(2):200-206
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Color defines one aspect of quality for tomato and tomato products. Carotenoid pigments are responsible for the red and orange colors of tomato fruit, and thus color is also of dietary interest. The aims of this study were (1) to determine the relative importance of field sampling and analytical replication when measuring lycopene and beta-carotene in tomato fruit and (2) to determine the effect of yellow shoulder disorder (YSD) on the content of lycopene and beta-carotene in tomato juice and tissue. Our results show that increasing biological replications is an efficient strategy for reducing the experimental error associated with measurements of lycopene and beta-carotene. Analytical replications did not contribute significantly to observed variation, and therefore experimental efficiency will be gained by reducing analytical replications while increasing field replication. We found that YSD significantly reduces lycopene in affected tissue and in juice made from affected fruit. In contrast, beta-carotene concentrations were only reduced in affected tissue but were not significantly reduced in juice. With increasing interest in biofortified crops, modulating the carotenoid profile in tomato by minimizing YSD symptoms represents a strategy for improving tomato fruit quality that is currently supported by grower contract structure and processor grades. 相似文献
76.
Karen L. Webb David Pelletier Audrey N. Maretzki Jennifer Wilkins 《Agriculture and Human Values》1998,15(1):65-75
Several different evaluation issuesare perceived as important by people involved withinnovative projects intended to improve local food andnutrition systems; particularly the establishment oflocal food policy coalitions. Several such coalitionshave been formed in North America, Europe, andAustralia with the goal of improving community foodsecurity and promoting sustainable local food systems.Pioneer coalitions have served as models, yet therehas been little systematic evaluation of thesemodels. A qualitative study was conducted to identifyfactors that may hinder evaluation efforts. In grouptelephone interviews, we sought the views ofacademics, project organizers, and funders, a total of24 key informants. Pressures to evaluate were assessed differently bythe three groups of key informants. Academics felt thefocus of evaluation should be on the effectiveness ofthe process used to discuss issues and formulatepolicies and plans. Project organizers and fundersperceived a need to assess project impact andoutcomes. A lack of suitable evaluation models andmethods was viewed as a formidable barrier. The use ofinappropriate methods and premature impact evaluationwere noted as potential threats to projectsustainability. External constraints and resourcelimitations were also said to inhibit evaluationefforts. It appears that several other factors may also beimpeding progress in conducting more (and more useful)evaluations including: (1) the apparent negativeconnotation of evaluation and the limited benefitsexpected from evaluation by stakeholders, (2) a lackof consensus about important evaluation questions,(3) insufficient evaluation expertise among projectorganizers, and (4) inadequate appreciation ofincreasing accountability pressures. 相似文献
77.
Mathilde Bettembourg Audrey Dardou Alain Audebert Emilie Thomas Julien Frouin Emmanuel Guiderdoni Nourollah Ahmadi Christophe Perin Anne Dievart Brigitte Courtois 《Rice》2017,10(1):45
Background
Plant root systems play a major role in anchoring and in water and nutrient uptake from the soil. The root cone angle is an important parameter of the root system architecture because, combined with root depth, it helps to determine the volume of soil explored by the plant. Two genes, DRO1 and SOR1, and several QTLs for root cone angle have been discovered in the last 5 years.Results
To find other QTLs linked to root cone angle, a genome-wide association mapping study was conducted on two panels of 162 indica and 169 japonica rice accessions genotyped with two sets of SNP markers (genotyping-by-sequencing set with approximately 16,000 markers and high-density-rice-array set with approximately 300,000 markers). The root cone angle of all accessions was measured using a screen protractor on images taken after 1 month of plant growth in the Rhizoscope phenotyping system. The distribution of the root cone angle in the indica panel was Gaussian, but several accessions of the japonica panel (all the bulus from Indonesia and three temperate japonicas from Nepal or India) appeared as outliers with a very wide root cone angle. The data were submitted to association mapping using a mixed model with control of structure and kinship. A total of 15 QTLs for the indica panel and 40 QTLs for the japonica panel were detected. Genes underlying these QTLs (+/?50 kb from the significant markers) were analyzed. We focused our analysis on auxin-related genes, kinases, and genes involved in root developmental processes and identified 8 particularly interesting genes.Conclusions
The present study identifies new sources of wide root cone angle in rice, proposes ways to bypass some drawbacks of association mapping to further understand the genetics of the trait and identifies candidate genes deserving further investigation.78.
Audrey Geffen 《Aquaculture (Amsterdam, Netherlands)》1979,16(1):83-85
A rotating cage has been designed and tested which prevents the significant buildup of fouling communities and does not add to labor or construction costs. 相似文献
79.
Audrey A.Sanchez Andrew W.Bartlow Allison M.Chan Jeanne M.Fair Aaron A.Skinner Kelly Hutchins Maria A.Musgrave Emily M.Phillips Brent E.Thompson Charles D.Hathcock 《中国鸟类》2021,(2):141-149
Background: Accurate nestling age is valuable for studies on nesting strategies, productivity, and impacts on repro-ductive success. Most aging guides consist o... 相似文献
80.
Chetboul V Sampedrano CC Gouni V Concordet D Lamour T Ginesta J Nicolle AP Pouchelon JL Lefebvre HP 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2005,19(6):837-844
Right ventricular myocardial (RVM) motion is poorly documented. The objective of this study was to determine the variability of RVM velocities by tissue Doppler imaging (TDI) in healthy dogs (study 1), to analyze RVM motion in a large healthy canine population (study 2), and to compare the results with those obtained for the left ventricular free wall. Six healthy Beagle Dogs were monitored in study 1, and 64 healthy dogs of 14 different breeds were monitored in study 2. Velocities were recorded in 2 segments (basal and apical) of the right and left myocardial walls. In study 1, 36 TDI examinations were performed for 4 days, whereas a single TDI examination was performed on each dog in study 2. All velocity profiles included 1 positive systolic wave and 2 negative diastolic waves. The lowest intraday and interday coefficient of variation values of the right TDI variables were observed at the base (3.5-16.1%). The variability of the right apical velocities was much higher, with most coefficient of variation values > 15%. RVM velocities were higher in the basal than in the apical segments (P < .001) and were higher than the left velocities of the corresponding segment (P < .01). Body weight and breed had an effect on only a few right and left TDI variables. TDI provides a repeatable and reproducible method for evaluating basal RV function in the dog. These data also demonstrate the heterogeneity of the myocardial velocities between the left and the right ventricles and between the base and the apex. 相似文献