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31.
I. Thibault R. D. Hedger J. J. Dodson J.‐C. Shiao Y. Iizuka W.‐N. Tzeng 《Ecology of Freshwater Fish》2010,19(3):348-360
Thibault I, Hedger RD, Dodson JJ, Shiao J‐C, Iizuka Y, Tzeng W‐N. Anadromy and the dispersal of an invasive fish species (Oncorhynchus mykiss) in Eastern Quebec, as revealed by otolith microchemistry. Ecology of Freshwater Fish 2010: 19: 348–360. © 2010 John Wiley & Sons A/S Abstract – Rainbow trout (Oncorhynchus mykiss) is invading rivers bordering the St. Lawrence Estuary (Quebec, Canada). Some rivers in Eastern Quebec support self‐sustaining populations while adult vagrants are frequently captured in rivers where no reproduction has been confirmed. We hypothesised that the development of anadromy has promoted the species dispersal. Otolith Sr:Ca analyses revealed that although all fish captured in the upstream stocking region were freshwater residents, both anadromous and freshwater resident phenotypes were found downstream in Eastern Quebec. The proportion of fish exhibiting the anadromous life cycle increased with the distance from the stocking zone. Eastern Quebec steelhead migrated to sea at the same age but at a larger size than steelhead within their native range. Age at first reproduction was similar to that observed in native populations. The development of the anadromous life cycle enables this species to colonise new rivers following long‐distance migrations along the St. Lawrence Estuary corridor. 相似文献
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Identification and preliminary characterization of a 75-kDa hemin- and hemoglobin-binding outer membrane protein of Actinobacillus pleuropneumoniae serotype 1 
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下载免费PDF全文 Marie Archambault Jose Labrie Clment R. Rioux France Dumas Pierre Thibault Christopher Elkins Mario Jacques 《Canadian journal of veterinary research》2003,67(4):271-277
The reference strains representing serotypes 1 to 12 of Actinobacillus pleuropneumoniae biotype 1 were examined for their ability to utilize porcine hemoglobin (Hb) or porcine hemin (Hm) as iron sources for growth. In a growth promotion assay, all of the reference strains were able to use porcine Hb, and all strains except 2 were able to use porcine Hm. Using a preliminary characterization procedure with Hm- or Hb-agarose, Hm- and Hb-binding outer membrane proteins (OMPs) of approximately 75 kDa were isolated from A. pleuropneumoniae serotype 1 strain 4074 grown under iron-restricted conditions. Matrix-assisted laser desorption ionization/time-of-flight (MALDI-TOF) analysis revealed a number of common tryptic peptides between the Hb-agarose- and Hm-agarose-purified 75 kDa OMPs, strongly suggesting that these peptides originate from the same protein. A database search of these peptide sequences revealed identities with proteins from various Gram-negative bacteria, including iron-regulated OMPs, transporter proteins, as well as TonB-dependent receptors. Taken together, our data suggest that A. pleuropneumoniae synthesizes potential Hm- and Hb-binding proteins that could be implicated in the iron uptake from porcine Hb and Hm. 相似文献
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Marta Dordas-Perpinyà Laure Normandin Thibault Dhier Hubert Terris Anaïs Cochard Camille Frilley Fanny Huiban Jean-François Bruyas 《Reproduction in domestic animals》2020,55(3):374-383
The aim of this study was to assess the efficacy of different doses of buserelin acetate and another GnRH agonist, triptorelin acetate, in saline solution in a single subcutaneous injection, to induce ovulation of growing pre-ovulatory follicle in mare and compare it with the classical treatment of a single injection of hCG. The study is split into 3 experiments over different breeding seasons in the same stud with a random distribution of treatment. The first one was to compare the injection of 6 mg of buserelin with 1,500 IU of hCG; the second one consisted of comparing different doses of buserelin (6 mg and 3 mg); and the third one compared three different doses of buserelin (3, 2 and 1 mg), 0.1 mg of triptorelin with 1,500 IU of hCG as a control group. The results of all experiments showed the same efficacy between all treatments with mares ovulating between 24 and 48 hr after injection: experiment 1: hCG (78% n = 41) and buserelin 6 mg (90% n = 50); experiment 2: buserelin 6 mg (78,1% n = 192) and buserelin 3 mg (78% n = 341); and experiment 3: hCG (87% n = 106), buserelin 3 mg (84,7% n = 137), buserelin 2 mg (82,7% n = 104), buserelin 1 mg (87% n = 54) and triptorelin 0.1 mg (84,7% n = 72). In conclusion, this study contributes to erasing the dogma that has been established since 1975 that a single injection in solution without any long-acting excipient of a GnRH agonist cannot induce ovulation in the mare. This study also shows that a injection of 0.1 mg of triptorelin in solution is a good alternative for ovulation induction and is comparable to small doses of buserelin acetate in solution (1 mg) and 1,500 IU of the gold standard trigger hCG, mainly in countries where human formulation of buserelin is not available. 相似文献
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Haeler Elena Bergamini Ariel Blaser Stefan Ginzler Christian Hindenlang Karin Keller Christine Kiebacher Thomas Kormann Urs G. Scheidegger Christoph Schmidt Ronald Stillhard Jonas Szallies Alexander Pellissier Loïc Lachat Thibault 《Landscape Ecology》2021,36(1):89-104
Context
Dead wood is a key habitat for saproxylic species, which are often used as indicators of habitat quality in forests. Understanding how the amount and spatial distribution of dead wood in the landscape affects saproxylic communities is therefore important for maintaining high forest biodiversity.
ObjectivesWe investigated effects of the amount and isolation of dead wood on the alpha and beta diversity of four saproxylic species groups, with a focus on how the spatial scale influences results.
MethodsWe inventoried saproxylic beetles, wood-inhabiting fungi, and epixylic bryophytes and lichens on 62 plots in the Sihlwald forest reserve in Switzerland. We used GLMs to relate plot-level species richness to dead wood amount and isolation on spatial scales of 20–200 m radius. Further, we used GDMs to determine how dead wood amount and isolation affected beta diversity.
ResultsA larger amount of dead wood increased beetle richness on all spatial scales, while isolation had no effect. For fungi, bryophytes and lichens this was only true on small spatial scales. On larger scales of our study, dead wood amount had no effect, while greater isolation decreased species richness. Further, we found no strong consistent patterns explaining beta diversity.
ConclusionsOur multi-taxon study shows that habitat amount and isolation can strongly differ in the spatial scale on which they influence local species richness. To generally support the species richness of different saproxylic groups, dead wood must primarily be available in large amounts but should also be evenly distributed because negative effects of isolation already showed at scales under 100 m.
相似文献35.
The hippocampus is crucial for spatial memory formation, yet it does not store long-lasting memories. By combining functional brain imaging and region-specific neuronal inactivation in mice, we identified prefrontal and anterior cingulate cortices as critical for storage and retrieval of remote spatial memories [correction]. Imaging of activity-dependent genes also revealed an involvement of parietal and retrosplenial cortices during consolidation of remote memory. Long-term memory storage within some of these neocortical regions was accompanied by structural changes including synaptogenesis and laminar reorganization, concomitant with a functional disengagement of the hippocampus and posterior cingulate cortex [correction]. Thus, consolidation of spatial memory requires a time-dependent hippocampal-cortical dialogue, ultimately enabling widespread cortical networks to mediate effortful recall and use of cortically stored remote memories independently. 相似文献
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Van Droogenbroeck C Beeckman DS Verminnen K Marien M Nauwynck H Boesinghe Lde T Vanrompay D 《Veterinary microbiology》2009,135(1-2):78-81
Two groups of five 1-day-old conventional turkeys were housed in negative pressure stables to become experimentally infected with Avian Metapneumovirus (aMPV) and Ornithobacterium rhinotracheale (ORT) at the age of 3 weeks. However, during the first 2 weeks, turkeys started to show respiratory disease characterized by rhinitis and dyspnoea. Routine bacterial and viral diagnoses remained negative. Therefore, pharyngeal swabs from the turkeys and from the veterinary scientist handling the animals were examined for the presence of Chlamydophila (C.) psittaci by using a combination of cell culture, nested PCR and ompA genotype-specific quantitative real-time PCR, as well as by serology. Results revealed simultaneous transmission of C. psittaci outer membrane protein A (ompA) genotypes D, F and E/B from infected turkeys to the veterinary scientist. 相似文献
38.
Riss J Décordé K Sutra T Delage M Baccou JC Jouy N Brune JP Oréal H Cristol JP Rouanet JM 《Journal of agricultural and food chemistry》2007,55(19):7962-7967
The effects of spirulina and its chromophore phycocyanin, both without bound Se or selenium-enriched, were studied on plasma cholesterol, early atherosclerosis, cardiac production of superoxide anions, and NAD(P)H oxidase expression in hamsters. Forty hamsters were divided into 5 groups of 8 and fed an atherogenic diet for 12 weeks. They received by gavage either 7.14 mL/(kg day) phycocyanin (PC), Se-rich phycocyanin (SePC), spirulina (SP) or Se-rich spirulina (SeSP) in water, or water as control. SeSP and SePC supplied 0.4 microg of Se per 100 g body weight. Plasma cholesterol and non-HDL cholesterol concentrations were lower in group consuming SePC. HDL-cholesterol was never affected. SePC significantly increased plasma antioxidant capacity by 42% compared with controls. A sparing effect in liver glutathione peroxidase (87% on average) and superoxide dismutase (56% on average) activity was observed for all the groups compared to controls. Aortic fatty streak area was significantly reduced in the experimental groups, especially by PC (82%) and SePC (85%). Cardiac production of superoxide anion significantly decreased by approximately 46-76% in the four experimental groups and especially in SePC group (76%). The expression of p22phox subunit of NAD(P)H oxidase decreased by 34% after consumption of SePC. The results indicate that chronic consumption of Se-rich spirulina phycocyanin powerfully prevents the development of atherosclerosis. The underlying mechanism is related mainly to inhibiting pro-oxidant factors and at a lesser extent improving the serum lipid profile. 相似文献