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81.
Geoffroy Séré Christophe Schwartz Stéphanie Ouvrard Jean-Christophe Renat Françoise Watteau Geneviève Villemin Jean Louis Morel 《Journal of Soils and Sediments》2010,10(7):1246-1254
Purpose
Constructed soils are Technosols resulting from the deliberate combination of various artefacts. Similarly to natural soils, technogenic parent materials are transformed by pedogenic factors contributing to their evolution. This work was conducted to study the first stages of the pedogenesis of constructed soils. 相似文献82.
Demeure O Sanchez MP Riquet J Iannuccelli N Demars J Fève K Kernaleguen L Gogué J Billon Y Caritez JC Milan D Bidanel JP 《Journal of animal science》2005,83(9):1979-1987
Pig chromosome 7 (SSC 7) has been shown to be rich in QTL affecting performance and quality traits. Most studies mapped the QTL close to the swine leukocyte antigens (SLA), which has a large effect on adaptability and natural selection. Previous comparative mapping studies suggested that the 15-cM region limited by markers LRA1 (mapped at 55 cM) and S0102 (mapped at 70 cM) contains hundreds of genes. To decrease the number of candidate genes, we improved the mapping resolution with a genetic chromosome dissection through a backcross recombinant progeny test program between Meishan (MS) and European (EU; i.e., Large White or Landrace) breeds. Three first-generation backcross--(EU x MS) x EU--and two second-generation backcross--([EU x MS] x EU) x EU--sires carrying a recombination in the QTL mapping interval were progeny-tested (i.e., measured for a total of 44 growth, fatness, carcass and meat quality traits). Progeny family size varied from 29 to 119 pigs. Animals were genotyped for markers covering the region of interest. Progeny-test results allowed the QTL interval to be decreased from 15 to 20 cM down to 10 cM, and even less than 6 cM if we assumed that the EU pigs used in this study share only one QTL allele. Except for a putative QTL affecting some carcass composition traits, the SLA is excluded as a candidate region, suggesting that it might be possible to apply a marker-assisted selection strategy for this QTL, while controlling SLA allele diversity. The strong QTL effects remaining in animals with only 12.5% (issued from first-generation backcross boars) and 6.25% (issued from second-generation back-cross boars) Meishan genetic background shows that epistatic interactions are likely to be limited. Finally, the QTL does not have strong effects on meat quality traits. 相似文献
83.
Chetboul V Tessier D Borenstein N Delisle F Zilberstein L Payen G Leglaive E Franc B Derumeaux G Pouchelon JL 《Journal of the American Veterinary Medical Association》2003,223(8):1159-62, 1129
A thoracic aortic aneurysm was diagnosed in a 6-month-old male Leonberg dog by use of radiography, transthoracic and transesophageal echocardiography, and magnetic resonance imaging. The aneurysm was associated with a twisted ascending aorta and dilatation of several other thoracic arteries (pulmonary trunk, brachiocephalic trunk, and left subclavian artery). Histologic examination of the aorta revealed cystic medial necrosis, with disruption of the elastic network, collagen fibers, and the muscle glycoprotein fibrillin-1. The dam and sire of the dog and 8 littermates were examined by use of transthoracic echocardiography. The sire and 1 male littermate also had an aneurysm of the ascending aorta. To the authors' knowledge, this is the first report of familial aortic aneurysm in dogs. 相似文献
84.
An m:n matched case–control study was conducted to identify risk factors for ovine clinical mastitis (CM). Data were from a national sheep registry and only ewes that lambed in the spring of 2004 were included. Eligible cases (n = 2857) and controls (n = 76,716) from 1056 flocks of meat sheep were matched on flock and conditional logistic regression was used for analysis of the data. CM risk was associated with age of the ewe and whether or not assistance at lambing was needed owing to dystocia; however, the effects of both these factors were modified by the number of lambs born. In ewes with 1 lamb, increasing age was associated with increased odds of CM (OR = 1.2 for each 1-year increase), while only a slight numerical increase in the odds was observed in ewes with >1 lamb. Dystocia was associated with increased odds of CM in ewes with 1 lamb (OR = 1.7) or 2 lambs (OR = 1.4), while no association was observed in ewes with >2 lambs. The odds of CM increased markedly with increasing number of lambs born to the ewe. For example, odds for 2-year-old ewes without dystocia were 6.7 times greater for those with >3 lambs than for those with 1 lamb. Compared with ewes of old Norwegian breeds, ewes of other breeds were more likely to experience CM (OR = 1.7). Ewes treated for CM at least once during the preceding 3 years had 4.0 times greater odds of CM compared with ewes without a CM history. It is likely that the effect estimates from this study, which are adjusted for breed and unaffected by inter-flock variations, are valid also for other meat sheep populations. 相似文献
85.
Vatn S Framstad T Torsteinbø WO 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2000,29(2):62-68
Abstract: A study was performed to evaluate blood from young lambs using the Technicon H*1 hematology analyzer, with emphasis on RBC parameters, comparison of tripotassium EDTA and heparin, and the effects of storage on heparinized blood. Blood samples from lambs 2 days to 18 weeks of age were analyzed within 6 hours, revealing a high precision, except for WBC counts in heparinized blood. The HCT values estimated by the H*1 correlated well (r2 = .90) with those obtained by the microhematocrit method. Mean hematologic values obtained for heparinized blood differed by up to 4% from values obtained for blood collected into EDTA. WBC counts decreased 8.4% in heparinized blood stored at 4°C for 1 day, but differences observed in RBC counts were ≤ 2%. Problems occurred when analyzing blood from young lambs with low hemoglobin values because the H*1 incorrectly counted microcytes with volumes of < 10 fL as platelets. When the necessary corrections were performed, the H*1 was useful for analyzing RBC parameters in lamb blood collected both into EDTA and into heparin. 相似文献
86.
Gry M. Grøneng Laura E. Green Jasmeet Kaler Synnøve Vatn Petter Hopp 《Preventive veterinary medicine》2014
In 2008, ovine footrot was detected in Norway for the first time since 1948. By December 2012 it had spread to 99 flocks, all in the county of Rogaland in the south west of Norway, and 42% of which were located in the municipality of Rennesøy in Rogaland. The aim of this study was to investigate risk factors for contracting severe footrot in flocks of sheep. A flock was considered positive for severe footrot based on positive virulence test or by clinical signs in addition to a positive PCR test. 相似文献
87.
Sustainability and multifunctionality in French farms: Analysis
of the implementation of Territorial Farming Contracts 总被引:1,自引:0,他引:1
Mohamed Gafsi Geneviève Nguyen Bruno Legagneux Patrice Robin 《Agriculture and Human Values》2006,23(4):463-475
Sustainable agriculture and ways to achieve it are important issues for agricultural policy. However, the concept of sustainability has yet to be made operational in many agricultural situations, and only a few studies so far have addressed the implementation process of sustainable agriculture. This paper provides an assessment of the Territorial Farming Contracts (TFC) – the French model for implementing sustainable agriculture – and aims to give some insights into the ways to facilitate the development of sustainable farming. Using a systems approach, the founding concept of the TFC model, an analysis has been made of the TFCs signed in the Midi-Pyrenees Region in south-western France. The results show that the first aspect of sustainability apparent in farmers’ projects referred to economic objectives. The environmental and social aspects were not foremost in the farming changes undertaken. In addition, the territorial dimension of the TFC was under-addressed. The majority of TFCs reveal a moderate or even low convergence with territorial priorities. These results are explained partly by the dominance of professional farming organizations in the implementation of TFC, and they imply that the organizational social dimensions of sustainability must not be neglected.
Mohamed
Gafsi
is an assistant professor of farm management at the National School of Agronomic Training. He received his PhD in management science at the University of Bourgogne. His research interests include farm management and protection of natural resources, corporate environmental management, sustainable agriculture, and African family farms.
Geneviève Nguyen
is assistant professor in rural economics at the National Polytechnique Institute – National Superior School of Agronomy, in Toulouse. Her research interests include the dynamics of agrarian institutions in uncertain economies, the supply and organization of services in remote rural areas. Her research has been carried out in Europe, Africa, and Asia. She received her MA in Economics and her PhD in Agricultural Economics from the Ohio State University.
Bruno Legagneux
is assistant professor of farm management at the National Polytechnique Institute – National Superior School of Agronomy, in Toulouse. His research interests include farm management and the entry of young farmers into farming.
Patrice Robin
is an engineer agronomist. He received his diploma from the National Superior School of Agronomy, in Montpellier. He is currently a doctoral candidate at the University of Toulouse. His research interests include agriculture and rural development, environmental issues, and food quality. 相似文献
88.
Christen D Tharin M Perrin-Cherioux S Abou-Mansour E Tabacchi R Défago G 《Journal of agricultural and food chemistry》2005,53(18):7043-7051
Eutypine, 4-hydroxybenzaldehyde, and 3-phenyllactic acid are some of the phytotoxins produced by the pathogens causing Eutypa dieback and esca disease, two trunk diseases of grapevine (Vitis vinifera). Known biocontrol agents such as Fusarium lateritium and Trichoderma sp. were screened for their ability to consume these toxins. Transformation time courses were performed, and an high-performance liquid chromatography-based method was developed to analyze toxin metabolism and to identify and quantify the converted products. The results show that the aldehyde function of eutypine was reduced to eutypinol, as by V. vinifera cv. Merlot, the cultivar tolerant to Eutypa dieback. We revealed a supplementary detoxification pathway, not known in Merlot, where the aldehyde function was oxidized to eutypinic acid. Moreover, some strains tested could further metabolize the transformation products. Every strain tested could transform 4-hydroxybenzaldehyde to the corresponding alcohol and acid, and these intermediates disappeared totally at the end of the time courses. When biological assays on cells of V. vinifera cv. Chasselas were carried out, the transformation products exhibited a lower toxicity than the toxins. The possibility of selecting new biocontrol agents against trunk diseases of grapevine based on microbial detoxification is discussed. 相似文献
89.
Miguel-Angel Franco-Nava Jean-Paul Blancheton Genevi ve Deviller Jean-Yves Le-Gall 《Aquacultural Engineering》2004,31(3-4):135-155
The control of adverse effects and the possibility of removing suspended solids from recirculating aquaculture systems (RAS) are the principal challenges facing aquaculture engineers. However, their dynamics and transformations are not yet well known. In this study, carbon and nitrogen stable isotopes values (δ13C and δ15N) were used as tracers of particulate matter in a seabass RAS. An isotopic mixing model was employed to estimate the contributions of particulate sources. Feed (−22.1‰ for δ13C and 11.9‰ for δ15N), feces (−24.0‰ for δ13C and 6.4‰ for δ15N) and biofilm (−25.1‰ for δ13C and 12.9‰ for δ15N) were identified as main sources of particulate matter. The particle traps collected a mixing of 29% of uneaten feed and 71% of feces, when drum filter eliminated all remaining uneaten feed, shifting the isotopic signatures of suspended solids from −23.8 and 7.9‰ to −24.9 and 8.3‰ for δ13C and δ15N, respectively. The fish muscle (−18.6‰ for δ13C and 15.4‰ for δ15N) could reflect the isotopic variability of feed ingredients accumulated over time. The isotopic shifts indicate that the contribution of three sources depends on: (1) fish metabolism; (2) water treatment devices; and (3) bacterial bio-fouling into biofilter. 相似文献
90.
The surveys of natural gamma-emitting radionuclides and 137Cs in surface soils of coniferous forest sites in and around Izmir were conducted during 2003?C2004. The soil samples were collected from three different depths of 15 forest sites, particularly local wild edible mushrooms areas. The average activity concentrations and ranges of the natural radionuclides in the soils were as follows: 30 (14?C51) Bq kg?1 of 226Ra; 40 (17?C79) Bq kg?1 of 232Th; and 581 (308?C879) Bq kg?1 of 40K. Moreover, the values of 137Cs activity concentrations averaged over the depth sections varied from 20 to 82 Bq kg?1 with a mean value of 52 Bq kg?1. Accordingly, the levels of the studied natural radionuclides in the forest soils were within the range specified by UNSCEAR (2000) report for regular soils as well as the agricultural soils from the West Anatolia, while the measured activity levels of 137Cs in the forest soils were still high in contrast to agricultural soils after 16 years from the deposition of Chernobyl fallout. 相似文献