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61.
Semen freezing is an effective and safe solution for the cryopreservation of animal genetic resources and for the diffusion of the genetic progress. Actually, these techniques are not yet under control for the rabbit species partly because methods are not clearly defined. Thus, the aim of this work is to study the effect of antibiotics (Penicillin G, Streptomycin) routinely used in freezing semen on the thermodynamic properties of freezing media mainly used in rabbit species. Measurements realized by differential scanning calorimetry show that these antibiotics may change the temperature of crystallization and the quantity of ice formed in the freezing media considered. Our calorimetric approach underlined that the composition and the properties of the cryoprotective solutions should be studied more precisely. 相似文献
62.
Luquet E Garner TW Léna JP Bruel C Joly P Lengagne T Grolet O Plénet S 《Evolution; international journal of organic evolution》2012,66(6):1942-1952
Populations that have suffered from genetic erosion are expected to exhibit reduced average trait values or decreased variation in adaptive traits when experiencing periodic or emergent stressors such as infectious disease. Genetic erosion may consequentially modify the ability of a potential host population to cope with infectious disease emergence. We experimentally investigate this relationship between genetic variability and host response to exposure to an infectious agent both in terms of susceptibility to infection and indirect parasite-mediated responses that also impact fitness. We hypothesized that the deleterious consequences of exposure to the pathogen (Batrachochytrium dendrobatidis) would be more severe for tadpoles descended from European treefrog (Hyla arborea) populations lacking genetic variability. Although all exposed tadpoles lacked detectable infection, we detected this relationship for some indirect host responses, predominantly in genetically depleted animals, as well as an interaction between genetic variability and pathogen dose on life span during the postmetamorphic period. Lack of infection and a decreased mass and postmetamorphic life span in low genetic diversity tadpoles lead us to conclude that genetic erosion, while not affecting the ability to mount effective resistance strategies, also erodes the capacity to invest in resistance, increased tadpole growth rate, and metamorphosis relatively simultaneously. 相似文献
63.
Ishtiaq F Gilbert M Brown J Joyner P Sodnomdarjaa R Luttrell MP Stallknecht D Joly DO 《Journal of wildlife diseases》2012,48(3):768-775
Wild waterbirds sampled July 2006-September 2009 in Mongolia were tested for antibodies to avian influenza (AI) virus with the use of a commercially available blocking enzyme-linked immunosorbent assay. Antibodies were detected in 25% (572/2,282) of tested birds representing 26 species, and all antibody-positive samples were from 12 species in the orders Anseriformes and Charadriiformes. The highest antibody prevalence was in Ruddy Shelducks (Tadorna ferruginea; 61.7%; n=261; 95% confidence interval [CI] 55.8-67.6%), Whooper Swans (Cygnus cygnus; 38.4%; n=242; 95% CI 32.3-44.5%), Swan Geese (Anser cygnoides; 15%; n=127; 95% CI 8.6-21.4%), Bar-headed Geese (Anser indicus; 13%; n=738; 95% CI 10.3-15.1%), and Mongolian Gulls (Larus mongolicus; 3.9%; n=255; 95% CI 1.3-6.5%). There was no significant temporal or spatial variation in the presence of antibodies in the sampled species. However, Bar-headed Geese and Mongolian Gulls showed spatial variation in antibody prevalence in 2007 and 2008, respectively. Our study provides insights into the hatch year waterbirds' exposure to AI virus at their natal and molting sites in Mongolia. 相似文献
64.
Luciana F. Alves Marco A. Assis Juliano van Melis Ana L. S. Barros Simone A. Vieira Fernando R. Martins Luiz A. Martinelli Carlos A. Joly 《Ecological Research》2012,27(2):323-332
Lianas play a key role in forest structure, species diversity, as well as functional aspects of tropical forests. Although
the study of lianas in the tropics has increased dramatically in recent years, basic information on liana communities for
the Brazilian Atlantic Forest is still scarce. To understand general patterns of liana abundance and biomass along an elevational
gradient (0–1,100 m asl) of coastal Atlantic Forest, we carried out a standard census for lianas ≥1 cm in five 1-ha plots
distributed across different forest sites. On average, we found a twofold variation in liana abundance and biomass between
lowland and other forest types. Large lianas (≥10 cm) accounted for 26–35% of total liana biomass at lower elevations, but
they were not recorded in montane forests. Although the abundance of lianas displayed strong spatial structure at short distances,
the present local forest structure played a minor role structuring liana communities at the scale of 0.01 ha. Compared to
similar moist and wet Neotropical forests, lianas are slightly less abundant in the Atlantic Forest, but the total biomass
is similar. Our study highlights two important points: (1) despite some studies have shown the importance of small-scale canopy
disturbance and support availability, the spatial scale of the relationships between lianas and forest structure can vary
greatly among tropical forests; (2) our results add to the evidence that past canopy disturbance levels and minimum temperature
variation exert influence on the structure of liana communities in tropical moist forests, particularly along short and steep
elevational gradients. 相似文献
65.
66.
Pernet V Joly S Dalkara D Schwarz O Christ F Schaffer D Flannery JG Schwab ME 《Cell death and differentiation》2012,19(7):1096-1108
Nogo-A, an axonal growth inhibitory protein known to be mostly present in CNS myelin, was upregulated in retinal ganglion cells (RGCs) after optic nerve injury in adult mice. Nogo-A increased concomitantly with the endoplasmic reticulum stress (ER stress) marker C/EBP homologous protein (CHOP), but CHOP immunostaining and the apoptosis marker annexin V did not co-localize with Nogo-A in individual RGC cell bodies, suggesting that injury-induced Nogo-A upregulation is not involved in axotomy-induced cell death. Silencing Nogo-A with an adeno-associated virus serotype 2 containing a short hairpin RNA (AAV2.shRNA-Nogo-A) or Nogo-A gene ablation in knock-out (KO) animals had little effect on the lesion-induced cell stress or death. On the other hand, Nogo-A overexpression mediated by AAV2.Nogo-A exacerbated RGC cell death after injury. Strikingly, however, injury-induced sprouting of the cut axons and the expression of growth-associated molecules were markedly reduced by AAV2.shRNA-Nogo-A. The axonal growth in the optic nerve activated by the intraocular injection of the inflammatory molecule Pam3Cys tended to be lower in Nogo-A KO mice than in WT mice. Nogo-A overexpression in RGCs in vivo or in the neuronal cell line F11 in vitro promoted regeneration, demonstrating a positive, cell-autonomous role for neuronal Nogo-A in the modulation of axonal regeneration. 相似文献
67.
Martin Gilbert Losolmaa Jambal William B. Karesh Amanda Fine Enkhtuvshin Shiilegdamba Purevtseren Dulam Ruuragchaa Sodnomdarjaa Khuukhenbaatar Ganzorig Damdinjav Batchuluun Natsagdorj Tseveenmyadag Purevsuren Bolortuya Carol J. Cardona Connie Y. H. Leung J. S. Malik Peiris Erica Spackman David E. Swayne Damien O. Joly 《PloS one》2012,7(9)
Mongolia combines a near absence of domestic poultry, with an abundance of migratory waterbirds, to create an ideal location to study the epidemiology of highly pathogenic avian influenza virus (HPAIV) in a purely wild bird system. Here we present the findings of active and passive surveillance for HPAIV subtype H5N1 in Mongolia from 2005–2011, together with the results of five outbreak investigations. In total eight HPAIV outbreaks were confirmed in Mongolia during this period. Of these, one was detected during active surveillance employed by this project, three by active surveillance performed by Mongolian government agencies, and four through passive surveillance. A further three outbreaks were recorded in the neighbouring Tyva Republic of Russia on a lake that bisects the international border. No HPAIV was isolated (cultured) from 7,855 environmental fecal samples (primarily from ducks), or from 2,765 live, clinically healthy birds captured during active surveillance (primarily shelducks, geese and swans), while four HPAIVs were isolated from 141 clinically ill or dead birds located through active surveillance. Two low pathogenic avian influenza viruses (LPAIV) were cultured from ill or dead birds during active surveillance, while environmental feces and live healthy birds yielded 56 and 1 LPAIV respectively. All Mongolian outbreaks occurred in 2005 and 2006 (clade 2.2), or 2009 and 2010 (clade 2.3.2.1); all years in which spring HPAIV outbreaks were reported in Tibet and/or Qinghai provinces in China. The occurrence of outbreaks in areas deficient in domestic poultry is strong evidence that wild birds can carry HPAIV over at least moderate distances. However, failure to detect further outbreaks of clade 2.2 after June 2006, and clade 2.3.2.1 after June 2010 suggests that wild birds migrating to and from Mongolia may not be competent as indefinite reservoirs of HPAIV, or that HPAIV did not reach susceptible populations during our study. 相似文献
68.
Biobanks are adopting various modes of public engagement to close the agency gap between participants and biobank builders. We propose a wiki-governance model for biobanks that harnesses Web 2.0, and which gives citizens the ability to collaborate in biobank governance and policymaking. 相似文献
69.
70.