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101.
New perspectives on aquarium fish trade 总被引:1,自引:0,他引:1
David Lecchini Sandrine Polti Yohei Nakamura Pascal Mosconi Makoto Tsuchiya Georges Remoissenet Serge Planes 《Fisheries Science》2006,72(1):40-47
ABSTRACT: Since the 1990s, the international market for importing aquarium fish is suspicious of stock coming from South-East Asia. Fish catches are still executed with cyanide-based toxic products. In the present paper, the potential of the French Polynesian Islands to develop a marine aquarium fish business with a new approach is explored. Coral reef fish are captured at the larval stage with crest nets, then larvae are reared in aquaria before being put on the world ornamental fish market. This approach offers several advantages: (i) larvae are captured with a passive system placed on the reef crest (crest net) that does not destroy the environment and limits the stress on collected larvae; (ii) larvae are then put into farmed basins that allow them to be controlled sanitarily; and (iii) larvae are weaned at the farm and fed rapidly with artificial food. This method increases survival rates as it eliminates the food acclimatization problem of fish captured at adult stage (main cause of fish mortality in aquaria). Overall, reared larvae will constitute a new product in terms of species, sizes and quality of ornamental fish on the aquarium market. 相似文献
102.
von Bernuth H Picard C Jin Z Pankla R Xiao H Ku CL Chrabieh M Mustapha IB Ghandil P Camcioglu Y Vasconcelos J Sirvent N Guedes M Vitor AB Herrero-Mata MJ Aróstegui JI Rodrigo C Alsina L Ruiz-Ortiz E Juan M Fortuny C Yagüe J Antón J Pascal M Chang HH Janniere L Rose Y Garty BZ Chapel H Issekutz A Maródi L Rodriguez-Gallego C Banchereau J Abel L Li X Chaussabel D Puel A Casanova JL 《Science (New York, N.Y.)》2008,321(5889):691-696
MyD88 is a key downstream adapter for most Toll-like receptors (TLRs) and interleukin-1 receptors (IL-1Rs). MyD88 deficiency in mice leads to susceptibility to a broad range of pathogens in experimental settings of infection. We describe a distinct situation in a natural setting of human infection. Nine children with autosomal recessive MyD88 deficiency suffered from life-threatening, often recurrent pyogenic bacterial infections, including invasive pneumococcal disease. However, these patients were otherwise healthy, with normal resistance to other microbes. Their clinical status improved with age, but not due to any cellular leakiness in MyD88 deficiency. The MyD88-dependent TLRs and IL-1Rs are therefore essential for protective immunity to a small number of pyogenic bacteria, but redundant for host defense to most natural infections. 相似文献
103.
Barbara Chaves Stefaan De Neve Maria del Carmen Lillo Cabrera Pascal Boeckx Oswald Van Cleemput Georges Hofman 《Biology and Fertility of Soils》2005,41(6):411-418
Manipulating the N release from high-N crop residues by simultaneous mixing of these residues with organic biological waste (OBW) materials seems to be a possible method to reduce NO3– leaching. The aim of this study was to examine whether the incorporation of OBW materials together with a high-N crop residue (celery) had also an effect on N2O emission from horticultural soil under short-term and optimised laboratory conditions. A sandy loam soil and celery residues were mixed with different OBW materials and brought into PVC tubes at 80% water-filled pore space and 15°C. Every 2.5 h, a gas sample was taken and analysed by gas chromatography for its N2O concentration. The soil amended with only celery residues had a cumulative N2O emission of 9.6 mg N kg–1 soil in 50 h. When the celery residues were mixed with an OBW material, the N2O emission was each time lower than the emission from the celery-only treatment (between 3.8 and 5.9 mg N kg–1 soil during maximum 77 h), except with paper sludge (17.2 mg N kg–1 soil in 100 h). The higher N2O emission from the paper sludge treatment was probably due to its unusually low C:N ratio. Straw, green waste compost 1 (GWC1) and 2 (GWC2), saw dust, and tannic acid reduced the N2O emission of the celery treatment by 40 to 60%. Although the N2O reduction potential can be expected to be lower and with differing dynamics under field conditions, this study indicates that apart from reducing NO3– leaching, OBW application may at the same time reduce N2O emissions after incorporation of high-N crop residues. 相似文献
104.
Molecular assays for detection of falcon adenovirus. 总被引:1,自引:0,他引:1
Mark Schrenzel Eric Snook Pascal Gagneux 《Journal of veterinary diagnostic investigation》2007,19(5):479-485
Falcon adenovirus is a newly recognized member of the family Aviadenoviridae and includes 2 closely related strains that are pathogenic to several species of falcons. Peregrine falcons appear to be one of the primary reservoirs, but recent outbreaks suggest that other carrier species probably exist. To allow screening of captive birds for virus shedding and investigations of disease outbreaks, conventional and real-time, quantitative polymerase chain reaction (PCR) assays and an in situ hybridization technique were developed. The diagnostic protocols were used on tissue and fecal samples from 7 species or subspecies of falcons infected with adenovirus as well as adenoviruses from other birds and mammals. The assays were specific for falcon adenovirus and detected both strains of virus in fecal samples from living animals or frozen and formalin-fixed, paraffinized tissues. Together with established serologic tests for falcon adenovirus, these molecular assays are valuable tools for management and conservation of falcons in captivity and the wild. 相似文献
105.
Lamis?ChalakEmail author Ahmad?Elbitar Reine?Rizk Elia?Choueiri Pascal?Salar Joseph?M.?Bové 《European journal of plant pathology / European Foundation for Plant Pathology》2005,112(1):85-89
Elimination of Candidatus phytoplasma phoenicium from two infected Lebanese varieties of almond by using different tissue culture techniques is reported. Except for the oxytetracycline therapy which totally inhibited the development of explants, stem cutting cultures associated with thermotherapy, shoot tip cultures associated or not with thermotherapy, and shoot tip micrografting were all suitable, either for shoot regeneration or for elimination of phytoplasma from the two varieties. However, stem cutting culture coupled with thermotherapy seemed to be the most effective for regeneration of phytoplasma-free plantlets. 相似文献
106.
107.
Lesnoff M Laval G Bonnet P Chalvet-Monfray K Lancelot R Thiaucourt F 《Preventive veterinary medicine》2004,62(2):101-117
Contagious bovine pleuropneumonia (CBPP) is a respiratory disease of cattle; CBPP is caused by Mycoplasma mycoides subsp. mycoides small colony. CBPP is a major cause for concern for African countries (because of mortality, animal-production losses and cost of control). The clinical form of the disease is the more infectious (contagion occurs essentially through coughing). However, chronic lung lesions with viable mycoplasmas can persist in recovering cattle. Animals presenting these lesions might have a time-delimitated infectious phase. Such carriers are suspected to generate field outbreaks (although this hypothesis remains debated). We investigated the potential quantitative effects of these chronic carriers on the within-herd CBPP spread. Data were collected during a longitudinal field herd survey in a mixed crop-livestock system in the Ethiopian highlands. Two stochastic Markov-chain models' outputs (seroconversion dynamics, basic reproduction ratio R0, cumulative clinical incidence and risk of herd infection) were compared given different hypotheses on the carrier infectiousness. The late seroconversions observed in the field data were fitted correctly only for the highest carrier infectiousness we considered (mean chronic duration of 1 year and carriers 50-times less infectious than clinical cases). Although sensitivities (in terms of disease impact in the herd) were in general negligible when the carrier infectiousness was low (e.g. when carriers were assumed to be 1000-times less infectious than clinical cases), they rapidly became important when the infectiousness increased. 相似文献
108.
Halloy DJ Kirschvink NA Vincke GL Hamoir JN Delvaux FH Gustin PG 《Veterinary journal (London, England : 1997)》2004,168(3):276-284
The aim of this work was to investigate whether the Penh index, measured using whole body barometric plethysmography, can be used as a screening parameter to evaluate the airway reactivity and the intensity of the pulmonary response to endotoxins. Penh was firstly recorded in non-sedated freely moving piglets exposed (1) to a nebulized acetylcholine (Ach) pre-treated or not with clenbuterol, or (2) to endotoxin challenge. To measure Penh simultaneously with total pulmonary resistance (R(L)), dynamic compliance (C(dyn)) and intrapleural pressure changes (Max Delta Ppl), an oesophageal balloon catheter technique was used and the piglets were anaesthetised. The recordings were performed during (1) an intravenous metacholine (Mch) challenge and (2) in endotoxin-exposed animals. In freely moving animals, Ach induced a significant dose-dependent increase in Penh, which was significantly blocked by clenbuterol. Endotoxin instillation also resulted in a significant rise in Penh while the corresponding response measured under anaesthesia was significantly and positively correlated with R(L) and Max Delta Ppl. Similar results were obtained during Mch challenge but the Penh was negatively correlated with C(dyn). We conclude that Penh could be used in freely moving piglets as a screening index for airway reactivity and pulmonary functional changes in cholinergic and endotoxin challenges. 相似文献
109.
Pascal Gentit René-Pierre Delbos Thierry Candresse Jean Dunez 《European journal of plant pathology / European Foundation for Plant Pathology》2001,107(5):485-494
A pathogen was transmitted from apricot trees showing symptoms of viral infection to GF305 peach seedlings which reacted by stunting, shortened internodes and chlorotic mottling. The agent was transmitted to cherry, apricot, peach and plum by grafting and to several herbaceous hosts by mechanical inoculation. Isometric nepovirus-like particles of 30–31 nm diameter extracted from infected Chenopodium quinoa sedimented as two peaks in sucrose gradients. These particles contained two single stranded RNAs of approximately 5.9 and 7.9 kb, and a single coat protein subunit of 53.7 kDa. No cross-reactions were observed with a number of nepoviruses infecting fruit trees. Inoculation of purified particles to herbaceous or woody hosts reproduced the same symptoms caused by the original isolate. Sequencing of a 2.2 kbp cDNA clone covering the 3 end of the small genomic RNA identified an open reading frame encoding a 317 aa N-truncated protein exhibiting significant similarities with the coat protein of nepoviruses. The 1257 nt long 3 non-coding region showed up to about 65% homology to the equivalent region of members of the subgroup C of nepoviruses. The properties of this pathogen do not match those of any previously described nepovirus. It should therefore be considered as a new member of the subgroup C of nepoviruses, for which the name of Apricot latent ringspot virus (ALRSV) is proposed.The nucleotide sequence reported in this work has been deposited in the EMBL databank under the accession number AJ278875. 相似文献
110.
Renaud Ioos Lise Laugustin Nathalie Schenck Sylvie Rose Claude Husson Pascal Frey 《European journal of plant pathology / European Foundation for Plant Pathology》2006,116(2):171-176
Introns are generally highly polymorphic regions within genes and were proven to be of great interest for discriminating among phylogenetically-close Phytophthora species. Phytophthora ramorum and P. fragariae are considered as quarantine pathogens by the European Union and accurate detection tools are therefore necessary for their monitoring. From introns located in different single copy genes (GPA1, RAS-like, and TRP1), we developed a series of PCR primers specific to P. ramorum and P. fragariae. The specificity of these primers was successfully checked with a wide collection of Phytophthora isolates and a protocol was developed to detect both pathogens directly in infected plant tissues. These genes should be of particular interest for the development of additional species-specific detection tools within the Phytophthora genus. 相似文献