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81.
Javier Del Amo Francisco Llorente Jordi Figuerola Ramón C Soriguer Ana M Moreno Paolo Cordioli Herbert Weissenb?ck Miguel ángel Jiménez-Clavero 《Veterinary research》2014,45(1):33
West Nile virus (WNV) is a zoonotic arboviral pathogen transmitted by mosquitoes in a cycle involving wild birds as reservoir hosts. The virus has recently emerged in North America and re-emerged in Europe. North American WNV outbreaks are often accompanied by high mortality in wild birds, a feature that is uncommon in Europe. The reason for this difference is unknown, but the intrinsic virulence of the viruses circulating in each continent and/or the susceptibility to the disease of Palearctic as opposed to Nearctic wild bird species could play a role. To assess this question, experimental inoculations with four lineage 1 WNV strains, three from southern Europe (Italy/2008, Italy/2009 and Spain/2007) and one from North America (NY99) were performed on house sparrows (Passer domesticus), a wild passerine common in both continents. Non-significant differences which ranged from 0% to 25% were observed in mortality for the different WNV strains. Viremias lasted from 1 to 5–6 days post-inoculation (dpi) in all cases; individuals inoculated with NY99 had significantly higher titres than those inoculated with any of the Euro-Mediterranean strains. Remarkably, host competence was found to be higher for NY99 than for the other strains. Consequently, albeit being pathogenic for house sparrows, some Euro-Mediterranean strains had reduced capacity for replication in -and transmission from- this host, as compared to the NY99 strain. If applicable also to other wild bird host species, this relatively reduced transmission capacity of the Euro-Mediterranean strains could explain the lower incidence of this disease in wild birds in the Euro-Mediterranean area. 相似文献
82.
Laura González Raúl Bermejo María Asunción Parra David Elustondo Jordi Garrigó Jesús Miguel Santamaría 《Water, air, and soil pollution》2010,206(1-4):23-34
Ground-level dynamics of O3, NO x and benzene, toluene, ethylbenzene and xylenes were characterised at rural sites in the medium Ebro River Basin (Northern Spain) from April to September (2003–2007) and by means of automated and passive monitoring. The study registered high O3 levels within the area, which were influenced by traffic emissions, and a monthly evolution of these levels consistent with the occurrence of a broad summer maximum, typical of polluted areas. The mean ozone concentration registered in the studied area by means of passive sampling was 87?±?12 μg m?3. The 2008/50/EC objective value for the protection of vegetation was widely exceeded during this study (AOT40?=?57,147?±?14,114 μg m?3 h), suggesting that current ambient levels may pose a risk for crops and vegetation in this important agroindustrial region. 相似文献
83.
Rodríguez A Solano-Gallego L Ojeda A Quintana J Riera C Gállego M Portús M Alberola J 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2006,20(3):495-498
Concentrations of Leishmania-specific immunoglobulin G (IgG), immunoglobulin M (IgM), and immunoglobulin A (IgA) isotypes were analyzed by enzyme-linked immunosorbent assay (ELISA) in 23 dogs naturally infected with Leishmania infantum before and 1 year after initiating drug therapy. Results showed a high expression and prevalence of Leishmania-specific IgG (176.4 +/- 89 ELISA units [EU]), IgM (105.3 +/- 95.5 EU), and IgA (153.6 +/- 98 EU) in dogs before treatment (median +/- interquartile range EU). One year after treatment was started, dogs were classified as responsive dogs (RDs; n = 13) or unresponsive dogs (UDs; n = 10) based on clinicopathologic findings. Both groups of dogs experienced a statistically significant decrease (P < .05) in Leishmania-specific IgG (RDs = 27%, UDs = 41%), IgM (RDs = 42%, UDs = 29%), and IgA (RDs = 56%, UDs = 46%). Concentrations of specific IgG and IgM were not different at diagnosis or after treatment between the 2 groups. However, the median value for Leishmania-specific IgA 1 year after treatment was significantly lower (P < .05) in RDs (60.8 +/- 67 EU) than in UDs (117 +/- 54 EU). Examination of our data indicates that both the IgA isotype, which is mostly produced by mucosal plasma cells, and the IgM isotype are increased in infected symptomatic dogs, as previously reported for IgG. These 3 isotypes decreased significantly 1 year after initiation of medical treatment. 相似文献
84.
López-Olvera JR Marco I Montané J Lavín S 《Veterinary journal (London, England : 1997)》2006,172(2):347-355
Chamois have been translocated for more than 100 years but their stress response to transport remains to be elucidated. In this study, 21 free-ranging Southern chamois were captured, physically restrained and then transported. The animals were randomly injected intramuscularly with acepromazine (nine adult males, one adult female and one yearling male) or saline (five adult males, two adult females and three yearling males). Heart rate and body temperature were monitored with telemetric devices, and blood samples were obtained at capture, immediately before and immediately after transport to determine haematological and serum biochemical parameters. Heart rate and blood parameters (erythrocytes, haemoglobin, packed cell volume, leukocytes, monocytes, band neutrophils, lactate, muscular enzymes and creatinine) indicated that transport was more stressful than previous physical restraint. Acepromazine reduced the adverse consequences of transport stress, as demonstrated by heart rate, body temperature, cortisol, creatinine, muscular enzymes, urea, sodium and potassium. 相似文献
85.
Fernández-Bellon H Solano-Gallego L Bardagí M Alberola J Ramis A Ferrer L 《Veterinary parasitology》2006,135(2):181-185
Leishmania infantum infection has recently been described in horses in Europe. We report the results of a study on the immune response to L. infantum in horses living in an area endemic for leishmaniosis in NE Spain. Two ELISAs using protein A and anti-horse IgG conjugates were adapted to measure specific antibodies to L. infantum in horse sera. A lymphocyte proliferation assay (LPA) of peripheral blood mononuclear cells to L. infantum antigen was also performed to detect specific cellular immune response to Leishmania. Anti-L. infantum antibodies were detected in the serum of 16 of the horses studied (n=112) using the protein A assay but not in the assay using the anti-horse IgG conjugate. Specific lymphocyte proliferation was observed in 20 out of 55 horses. This study shows that horses in the area studied mount specific immune responses to L. infantum, and must therefore be considered among the species exposed to the parasite in this region. The infrequency of leishmaniosis in horses suggests that the immune response in this species is effective in controlling the infection. 相似文献
86.
Balanza R García-Lorda P Pérez-Rodrigo C Aranceta J Bonet MB Salas-Salvadó J 《Public health nutrition》2007,10(2):168-176
OBJECTIVE: The aims of this study were to assess the changes that have occurred in food patterns in Europe over the last 40 years based on food availability data and to compare the stability of the traditional Mediterranean diet in the south of Europe in this period. DESIGN: An ecological study carried out on the basis of Food and Agriculture Organization food balance sheets for three geographical areas of Europe (Mediterranean, north and east) over two time periods: 1961-1963 and 1998-2000. The average availability of total energy, energy provided from macronutrients and food groups was calculated for each area and each period studied. RESULTS: Over the last 40 years total energy availability and energy availability from lipids have increased considerably in the three European areas, while the percentage of energy from carbohydrates has fallen. The greatest changes have occurred in Mediterranean Europe, with an increase of 20.1% in total energy availability, an increase of 48.1% in energy availability from lipids and a fall of 20.5% from carbohydrates. Moreover, Mediterranean Europe showed a significant fall in the energy supplied by cereals (29.9%) and wine (55.2%), while the contribution of milk (77.8%) and dairy products (23.6%) increased. CONCLUSIONS: The results of this study suggest that European Mediterranean countries should take nutrition policy action to maintain their traditional healthy food pattern, with a cultural added value. This implies actions at all levels, including raising awareness of consumers, collaboration with the food sector and a call to set the agenda of the concerned politicians and stakeholders. 相似文献
87.
Spermatological characters of the liver fluke Mediogonimus jourdanei Mas-Coma et Rocamora, 1978 were studied by means of transmission and scanning electron microscopy. Spermiogenesis begins with the formation of the differentiation zone containing two centrioles associated with striated rootlets and an intercentriolar body. These two centrioles originate two free flagella that undergo a 90 degrees rotation before fusing with the median cytoplasmic process. Both nuclear and mitochondrial migrations toward the median cytoplasmic process occur before the proximodistal fusion of flagella. Finally, the constriction of the ring of arched membranes gives rise to the young spermatozoon. The mature sperm of M. jourdanei measures about 260 microm and presents two axonemes of different lengths with the typical pattern of the Trepaxonemata, two bundles of parallel cortical microtubules, one mitochondrion, a nucleus and granules of glycogen. An analysis of all the microphalloidean species studied to date emphasised some differences in certain characters found in Maritrema linguilla J?gerski?ld, 1908 and Ganeo tigrinum Mehra et Negi, 1928 in comparison to those in the remaining microphalloideans. The presence and variability of such ultrastructural characters according to family, superfamily or order have led several authors to propose their use in the analysis of trematode relationships and phylogeny. Therefore, apart from producing new data on the family Prosthogonimidae, the present study also compares the spermatological organization of M jourdanei with other available ultrastructural studies focusing on the Microphalloidea. 相似文献
88.
Studies of ecological networks (the web of interactions between species in a community) demonstrate an intricate link between a community's structure and its long-term viability. It remains unclear, however, how much a community's persistence depends on the identities of the species present, or how much the role played by each species varies as a function of the community in which it is found. We measured species' roles by studying how species are embedded within the overall network and the subsequent dynamic implications. Using data from 32 empirical food webs, we find that species' roles and dynamic importance are inherent species attributes and can be extrapolated across communities on the basis of taxonomic classification alone. Our results illustrate the variability of roles across species and communities and the relative importance of distinct species groups when attempting to conserve ecological communities. 相似文献
89.
Evaluation of plant-based water status indicators in mature apple trees under field conditions 总被引:1,自引:0,他引:1
The performance of different indicators of plant water status as a tool for irrigation management was evaluated in mature
field grown ‘Golden Delicious’ apple trees during the late summer of 1998. Control (C) and stress (S) treatments were studied.
In the C treatment trees were irrigated daily at 100% ETc whereas in the S treatment water was withheld during 31 days (DOY’s 236–266). Predawn water potential (Ψpd) and midday stem water potential (Ψstem) were measured several times a week during the experimental period. Three daily measurements of stomatal conductance (gs) and stem water potential were made during five consecutive days in mid-September. Trunk diameter changes (TDC) were recorded
by LVDT sensors, and from these measurements, maximum daily shrinkage (MDS), daily growth (DG), and cumulative growth (CG)
were calculated. Midday Ψstem showed the best ratio between the response to moderate water stress and tree variability (“signal/noise” ratio) among the
indicators studied here, followed closely by Ψpd. On the other hand, the poorest water status indicator was gs. Due to the low trunk growth rate of the trees, and its high variability, DG and CG were not adequate indicators. MDS showed
a lower sensitivity to water stress and a higher variability (CV = 0.19) than midday Ψstem (CV = 0.08) and Ψpd (CV = 0.10). However, MDS correlated well with ET0 and with midday Ψstem (R
2 = 0.79) thus, making this parameter an interesting and promising tool for irrigation management in apple orchards. More research
needs to be done in order to define reference values for MDS and plant water potential indicators, in relation to evaporative
conditions and in different phenological periods, and to quantify the relationship between water status indicators values
and apple tree yield and fruit quality. 相似文献
90.
Yuliaxis Ramayo-Caldas Laura Zingaretti Milka Popova Jordi Estellé Aurelien Bernard Nicolas Pons Pau Bellot Núria Mach Andrea Rau Hugo Roume Miguel Perez-Enciso Philippe Faverdin Nadège Edouard Dusko Ehrlich Diego P. Morgavi Gilles Renand 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2020,137(1):49-59
Mitigation of greenhouse gas emissions is relevant for reducing the environmental impact of ruminant production. In this study, the rumen microbiome from Holstein cows was characterized through a combination of 16S rRNA gene and shotgun metagenomic sequencing. Methane production (CH4) and dry matter intake (DMI) were individually measured over 4–6 weeks to calculate the CH4 yield (CH4y = CH4/DMI) per cow. We implemented a combination of clustering, multivariate and mixed model analyses to identify a set of operational taxonomic unit (OTU) jointly associated with CH4y and the structure of ruminal microbial communities. Three ruminotype clusters (R1, R2 and R3) were identified, and R2 was associated with higher CH4y. The taxonomic composition on R2 had lower abundance of Succinivibrionaceae and Methanosphaera, and higher abundance of Ruminococcaceae, Christensenellaceae and Lachnospiraceae. Metagenomic data confirmed the lower abundance of Succinivibrionaceae and Methanosphaera in R2 and identified genera (Fibrobacter and unclassified Bacteroidales) not highlighted by metataxonomic analysis. In addition, the functional metagenomic analysis revealed that samples classified in cluster R2 were overrepresented by genes coding for KEGG modules associated with methanogenesis, including a significant relative abundance of the methyl-coenzyme M reductase enzyme. Based on the cluster assignment, we applied a sparse partial least-squares discriminant analysis at the taxonomic and functional levels. In addition, we implemented a sPLS regression model using the phenotypic variation of CH4y. By combining these two approaches, we identified 86 discriminant bacterial OTUs, notably including families linked to CH4 emission such as Succinivibrionaceae, Ruminococcaceae, Christensenellaceae, Lachnospiraceae and Rikenellaceae. These selected OTUs explained 24% of the CH4y phenotypic variance, whereas the host genome contribution was ~14%. In summary, we identified rumen microbial biomarkers associated with the methane production of dairy cows; these biomarkers could be used for targeted methane-reduction selection programmes in the dairy cattle industry provided they are heritable. 相似文献