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1.
The comparative effects of iron-supplemented levels on growth, tissue distribution, haematology and immunology of gilthead sea bream, Sparus aurata (2 g) were investigated, using four organic (50, 100, 200, 300 mg ORG/kg diet) and one inorganic iron source (200 INOR mg/kg diet). Fish were treated for 12 weeks with the experimental diets and maintained at a water temperature of 19–22°C. Growth (final weight and specific growth rate), tissue distribution (spleen, liver and muscle), haematological parameters (red blood cells, haematocrit, haemoglobin and mean corpuscular haemoglobin concentration) and non-specific immune indexes (respiratory burst activity and antibacterial activity of serum) were analysed. No significant differences were found in growth and iron tissue distribution among the tested groups. Red blood cell counting was statistically higher in fish given 50 ORG, 100 ORG, 200 ORG and 200 INOR feeds. However, haematocrit, haemoglobin and mean corpuscular haemoglobin concentration were not significantly affected by increasing dietary iron. Fish receiving the 100 ORG diet had the best performance with respect to the respiratory burst activity and significantly higher values for antibacterial activity of serum were obtained in fish fed with the 300 ORG diet. The present findings provided no clear evidence of the optimum iron concentration. However, there was adequate indication that iron supplementation enhanced the performance of gilthead sea bream, mainly from a haematological and immunological point of view.  相似文献   
2.
In developed countries, most of hepatitis E human cases are of zoonotic origin. Swine is a major hepatitis E virus (HEV) reservoir and foodborne transmissions after pork product consumption have been described. The risk for HEV-containing pig livers at slaughter time is related to the age at infection and to the virus shedding duration. Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) is a virus that impairs the immune response; it is highly prevalent in pig production areas and suspected to influence HEV infection dynamics. The impact of PRRSV on the features of HEV infections was studied through an experimental HEV/PRRSV co-infection of specific-pathogen-free (SPF) pigs. The follow-up of the co-infected animals showed that HEV shedding was delayed by a factor of 1.9 in co-infected pigs compared to HEV-only infected pigs and specific immune response was delayed by a factor of 1.6. HEV shedding was significantly increased with co-infection and dramatically extended (48.6 versus 9.7 days for HEV only). The long-term HEV shedding was significantly correlated with the delayed humoral response in co-infected pigs. Direct transmission rate was estimated to be 4.7 times higher in case of co-infection than in HEV only infected pigs (0.70 and 0.15 per day respectively). HEV infection susceptibility was increased by a factor of 3.3, showing the major impact of PRRSV infection on HEV dynamics. Finally, HEV/PRRSV co-infection – frequently observed in pig herds – may lead to chronic HEV infection which may dramatically increase the risk of pig livers containing HEV at slaughter time.

Electronic supplementary material

The online version of this article (doi:10.1186/s13567-015-0207-y) contains supplementary material, which is available to authorized users.  相似文献   
3.
In the bottlenose dolphin Tursiops truncatus, a massive retial complex is interposed between the systemic and cerebral circulations at the cervicothoracic level. Pressure measurements in the retial efferent arteries supplying the brain revealed relatively nonpulsatile pressure profiles. These measurements in the anesthetized dolphin demonstrate the pressure-damping effect of the retia mirabile.  相似文献   
4.
A yearling filly was presented for protrusion of a mass at the vulvar margins. A diagnosis of prolapse of the right uterine horn was made after vaginoscopy, transrectal palpation, and ultrasonography. It was confirmed later by biopsy of the tissue. Recovery was uneventful after easy replacement of the uterine horn.  相似文献   
5.
New Forests - Climate change is projected to increase fire severity and frequency in the boreal forest, but it could also directly affect post-fire recruitment processes by impacting seed...  相似文献   
6.
We tested the prediction that climate-driven changes might alter bird species composition in reserves of the Cerrado region of Brazil. First, we modelled the current distributions and the potential future projections of 38 endemic or rare bird species. We used eight modelling techniques within the BIOMOD computational framework in an ensemble-forecasting approach to reach a consensus scenario. Then we compared current and future (2046-2060) distributions under different scenarios (reserve size and bird dispersal) with the current Brazilian reserve system to assess the adequacy of protection (representation) of each species and detect gaps in their protection. Finally, to identify areas with high probability of occurrence of several species, we calculated cumulative climatic suitability of all 38 species for both current and future scenarios. None of the 38 species is covered under any current or future scenarios, revealing that the current reserve system is highly inefficient in conserving the analyzed bird species. The implementation of new reserves to cover species in current and future climate scenarios is recommended in areas in the south-eastern part of the Cerrado region and in the mountains of east Brazil. Due to the already high land use of the southeast region of the Cerrado, the application of non-traditional conservation measures should be evaluated.  相似文献   
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8.
Genetic maps published for elite durum wheat (Triticum turgidum durum Desf.), were mainly related to Italian and North American pools. To provide additional information dedicated to durum elite pool, a recombinant inbred population (217 RILs) derived form 2 French commercial varieties (Ixos and Primadur), has been mapped with 529 loci (98 AFLPs, 67 SSRs, 1 ISBP and 363 DArTs). Genetic map spanned a total of 2,082 cM (5.7 cM/marker on average). Recombination rate variation over the genome was documented through the analysis of six segregating populations representing a total of 48 RILs × 6, issued from an half diallel design based on four elite lines—Neodur, Ixos, Lloyd and Primadur—including the 2 previous genitors. Each set of three genetically connected populations (48 RILs × 3) was used to build the consensus parental maps for each genitor. To construct the four consensus parental maps, marker ordering was determined on 217 RILs map which was an extended population of the most polymorphic cross (Ixos × Primadur). Sizeable, recombination rate variation has been observed between the four parental maps both at the marker pair scale and at the linkage group scale. Two of the parents, Lloyd and Primadur, had strong, opposite effects increasing and decreasing, respectively the recombination rate. Additional studies are proposed to increase our understanding of this variation, with the identification of environmental or genetic factors affecting recombination rate.  相似文献   
9.
The efficacy of fluorescent pseudomonads as suppressors of soil-borne diseases is linked to their ability to colonise plant roots. Monitoring the dynamics of biocontrol agents in the rhizosphere should improve the irreliability. We designed a pair of Sequenced Characterised Amplified Region (SCAR) primers specific to Pseudomonas fluorescens Pf29A, based on a specific 700 bp RAPD product selected in a previous work. Primer specificity was tested with DNA samples extracted from rhizospheric soil and rhizoplane of wheat plants grown in two different non-sterile soils. We assessed the total population of Pf29A by PCR and the culturable population by counting a tetracycline-resistant Pf29A transformant producing Green Fluorescent Protein (GFP), on selective medium 5 days after inoculation of non-sterile soil. SCAR primers were specific for Pf29A in both soils. We evaluated the limit of detection to 14.2 fg of target DNA, equivalent to 242 Pf29A cells per cm of wheat root. Culturable populations of Pf29A transformant accounted for 13% and 4% of the total populations 5 days after treatment with 103 and 107 CFU of transformed Pf29A per gram of soil. The SCAR derived sequence is a good candidate to develop a strain specific and sensitive PCR-quantification of Pf29A available for population dynamic studies in fields. We confirm that only a small proportion of the total Pf29A rhizosphere population is culturable.  相似文献   
10.
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