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121.
Two species of Cryptosporidium are commonly identified in pigs: Cryptosporidium suis and Cryptosporidium pig genotype II. Detection of Cryptosporidium spp. is routinely based on molecular methods such as polymerase chain reaction (PCR) and subsequent restriction fragment length polymorphism (RFLP) or gene sequencing. However, most of these methods are hampered by low sensitivity to mixed infections. As a solution of this problem, novel species-specific primers were designed and tested in the present study. Sensitivity of our primers was identical to genus-specific primers, but more (1:48) mixed infections were detected using these species-specific primers on 477 DNA samples originating from naturally infected pigs of different age categories. Our results show differences in age-dependent susceptibility of pigs to the infection. Whereas C. suis was found in all tested categories of pigs (1-12 week of age and sows), Cryptosporidium pig genotype II was recorded only in animals older than 6 week of age. Usage of species-specific primers could help to better the understanding of epidemiology of pig specific Cryptosporidium spp. and its occurrence, which, on the basis of our results, is underestimated. 相似文献
122.
Bielaszewska M Zhang W Mellmann A Karch H 《Berliner und Münchener tier?rztliche Wochenschrift》2007,120(7-8):279-287
Enterohaemorrhagic Escherichia coli (EHEC) O26:H11 have emerged as the most important non-O157:H7 EHEC, with respect to their ability to cause diarrhoea and the haemolytic uraemic syndrome (HUS). HUS is a leading cause of acute renal failure in children, and is mainly caused by EHEC expressing Shiga toxins (Stx) 1 and/or 2. Since 1996, EHEC O26, which produce Stx2 only and appear to have enhanced virulence, have been increasingly isolated from HUS patients in Germany. In contrast, EHEC O26 found in cattle predominantly produce Stx1 as the sole Stx. Additional potential virulence factors of EHEC O26 include cytolysins (EHEC hemolysin), serine proteases (EspP), lymphotoxins (Efal) and adhesins (intimin). The genes encoding the virulence factors are located within pathogenicity islands (eae, efa1), bacteriophages (stx) or plasmids (EHEC-hlyA, espP). In addition, EHEC O26 possess, in contrast to other EHEC, the "high pathogenicity island" (HPI), which is also present in pathogenic Yersiniae.This island contains genes involved in the biosynthesis, regulation and transport of the siderophore yersiniabactin. Comparative genomic analyses between EHEC O26 and non-pathogenic E. coli, as well as investigations of mechanisms involved in the transfer of virulence genes, provide a deeper insight into the evolution of EHEC O26.These studies demonstrate how horizontal transfer of virulence genes, even from distantly related organisms, can lead in brief intervals to the rise of a highly virulent clone within a particular E. coli serotype.The classical bacteriological methods are no longer sufficient to determine the risk posed by EHEC O26. However, knowledge of the complete virulence profiles of these pathogens and understanding their stepwise evolution form a foundation for developing new strategies to prevent human infections and new methods for their laboratory diagnosis. 相似文献
123.
Velia-Isabel Hülsmeyer Katharina Flatz Katrin Putschbach Martina Ramona Bechter Sebastian Weiler Andrea Fischer Melanie Feist 《Irish veterinary journal》2015,68(1)
A 6-week-old female Simmental calf was evaluated for acute non-ambulatory tetraparesis. Physical and laboratory examinations revealed no clinically relevant abnormalities. Neurological findings were consistent with acute, progressive and painful cervical myelopathy. Radiographs displayed a fractured odontoid process (dens axis) and vertebral step misalignment at the fracture site. A traumatic origin was suspected. Advanced diagnostic imaging was considered to allow better planning of potential surgical stabilisation and to exclude any additional lesions of the cervical vertebral column. However, during trailer transportation to the advanced diagnostic imaging and surgery site, the calf deteriorated neurologically and was humanely euthanised. Magnetic resonance imaging (MRI) and computed tomography (CT) were performed immediately post-mortem for scientific reasons. The MRI examination reflected the radiographic findings and confirmed severe spinal cord compression at the fracture site. In addition, a T2W-hyperintense signal change within the paravertebral soft tissue dorsal to the fracture site was indicative of a traumatic event. CT identified the fracture site at the synchondrosis between the odontoid process and the body of the axis, and this finding was confirmed by post-mortem examination. Advanced diagnostic imaging and post-mortem examination did not identify any other cervical lesion. In summary, this calf was diagnosed with a traumatic odontoid process synchondrosis fracture, which has not been reported previously in calves but presents a challenging and well-known fracture type in young children. This case report indicates that the odontoid process synchondrosis is a potential predisposed injury site and that traumatic odontoid process synchondrosis fractures should be considered as a potential differential in calves with acute cervical pain and/or signs of a cervical myelopathy. 相似文献
124.
Marie M Meyerholz Kirsten Mense Michael Lietzau Ana Kassens Matthias Linden Hendrike Knaack Elisa Wirthgen Andreas Hoeflich Mariam Raliou Christophe Richard Olivier Sandra Hans-Joachim Schuberth Martina Hoedemaker Marion Schmicke 《Journal of veterinary science (Suw?n-si, Korea)》2015,16(4):413-421
This study was conducted to determine if the main components of the somatotropic axis change during the early phase of pregnancy in the maternal blood system and whether differences exist on day 18 after pregnancy recognition by the maternal organism. Blood samples of pregnant heifers (Holstein Friesian; n = 10 after embryo transfer) were obtained on the day of ovulation (day 0), as well as on days 7, 14, 16 and 18 and during pregnant, non-pregnant and negative control cycles. The oncentrations of progesterone (P4), oestrogen, growth hormone (GH), insulin-like growth factor-1 and -2 (IGF1, -2) and IGF-binding protein-2, -3 and -4 (IGFBP2, -3, -4) were measured. The mRNA expressions of growth hormone receptor 1A, IGF1, IGF2, IGFBP2, IGFBP3 and IGFBP4 were detected using RT-qPCR in liver biopsy specimens (day 18). In all groups, total serum IGF1 decreased from day 0 to 16. Notably, IGFBP4 maternal blood concentrations were lower during pregnancy than during non-pregnant cycles and synchronized control cycles. It can be speculated that the lower IGFBP4 in maternal blood may result in an increase of free IGF1 for local action. Further studies regarding IGFBP4 concentration and healthy early pregnancy are warranted. 相似文献
125.
Maike HEPPELMANN Karoline KRACH Lars KRUEGER Philipp BENZ Kathrin HERZOG Marion PIECHOTTA Martina HOEDEMAKER Heinrich BOLLWEIN 《The Journal of reproduction and development》2015,61(6):565-569
The objective of this study was to examine the effects of metritis and subclinical hypocalcemia on reduction
of uterine size in dairy cows using ultrasonography and sonomicrometry. Four piezoelectric crystals were
implanted via laparotomy into the myometrium of the pregnant uterine horn of 12 pluriparous Holstein Friesian
cows 3 weeks before the calculated calving date. Sonometric measurements were conducted daily from 2 days
before parturition (= Day 0) until Day 14 after calving and then every other day until Day 28. Distances
between adjacent crystals were expressed in relation to reference values obtained before calving. The diameter
of the formerly pregnant uterine horn was measured using transrectal B-Mode sonography starting on Day 10.
Cows were retrospectively divided into the following groups: cows without metritis (M–; n = 7), cows with
metritis (M+; n = 5), cows with normocalcemia (SH–; Ca > 2.0 mmol/l on Days 1 to 3; n = 5) and cows with
subclinical hypocalcemia (SH+; Ca < 2.0 mmol/l in at least one sample between Days 1 and 3; n = 7).
Metritis did not affect (P > 0.05) sonometric measurements, but the diameter of the formerly pregnant horn
was larger (P ≤ 0.05) between Days 15 and 21 in M+ cows than in M‒ cows. Reduction in uterine length in
hypocalcemic cows was delayed (P ≤ 0.05) between Days 8 and 21 compared with normocalcemic cows, but the
uterine horn diameter was not related to calcium status. In conclusion, both diseases affected reduction of
uterine size until Day 28. Cows with metritis had a larger uterine diameter, possibly attributable to
accumulation of lochia, and cows with subclinical hypocalcemia had delayed reduction of uterine length,
presumably related to reduction of myometrial contractility. 相似文献
126.
Martina I. Gocke Axel Don Arne Heidkamp Florian Schneider Wulf Amelung 《植物养料与土壤学杂志》2021,184(1):51-64
Background : In search for more sustainable crop production, the subsoil has recently come into focus as considerable reservoir of nutrients and water. Aims : Dimensions of subsoil phosphorus (P) reserves are yet largely unknown but crucial for identifying regions suitable to include subsoil into sustainable management strategies. Methods : We analyzed stocks of total and plant‐available (calcium acetate lactate‐extractable) P in 96 representative soil profiles of German arable land down to 1 m depth. Results : We found that the German arable soils stored, on average, 8 t ha?1 of total P, of which nearly 500 kg ha?1 were readily plant‐available. Notably, one third of plant‐available P was located below the plow layer and one fifth even at depths below 0.5 m. The depth gradients of plant‐available P stocks were affected more by major reference soil group than by texture. Generally, Chernozem but also Anthrosol, Gleysol and Fluvisol exhibited the largest P stocks in German cropland. The contribution of plant‐available P to total P stocks was larger in sandy and extremely acidic (pH < 4.5) soils compared with more fine‐grained and slightly acidic to alkaline soils, possibly because fertilization compensated for overall lower total P stocks at these sites. Generally, the more P was stored in topsoils, the more P was stored also in subsoils. Conclusions : A hypothetical crop utilization of 10% from plant‐available P stocks and 0.1% from total P stocks from shallow subsoil could compensate for P fertilization by ca. 8 kg ha?1, but the rate of plant‐available P replenishment in subsoil likely remains the crucial factor for the role of subsoil P stocks in crop nutrition. Generally, the large P reserves found in subsoil could act as an ‘insurance' system for crops. 相似文献
127.
Leinders-Zufall T Brennan P Widmayer P S PC Maul-Pavicic A Jäger M Li XH Breer H Zufall F Boehm T 《Science (New York, N.Y.)》2004,306(5698):1033-1037
The mammalian vomeronasal organ detects social information about gender, status, and individuality. The molecular cues carrying this information remain largely unknown. Here, we show that small peptides that serve as ligands for major histocompatibility complex (MHC) class I molecules function also as sensory stimuli for a subset of vomeronasal sensory neurons located in the basal Gao- and V2R receptor-expressing zone of the vomeronasal epithelium. In behaving mice, the same peptides function as individuality signals underlying mate recognition in the context of pregnancy block. MHC peptides constitute a previously unknown family of chemosensory stimuli by which MHC genotypic diversity can influence social behavior. 相似文献
128.
Martina Carrete Juan M. Grande José A. Sánchez-Zapata Ricardo Díaz-Delgado 《Biological conservation》2007,136(1):143-154
Extinctions are often the result of multiple factors that are difficult to disentangle and so methods for identifying simple and combined types of extinctions are valuable for both basic and applied ecology. We applied a modification of variance partitioning and a hierarchical partitioning analysis to test several hypotheses that attempt to explain the recent large-scale disappearance of Egyptian Vulture breeding territories in Spain. Our aim was to identify and then separate the simple (or pure) from the combined effects of habitat features, human pressure, and the social behavior of the species on the risk of extinction from a territory while controlling for spatial autocorrelation. Deviance partitioning showed that a complex mix of factors is significantly related to the disappearance of more than 400 territories throughout Spain. Abandoned territories were located in areas that are isolated from other conspecific territories and far from communal roost sites. In addition, these territories were found in places where there is a lack of natural habitats, high habitat fragmentation and reduced habitat diversity, and where food availability seems to be low and the illegal use of poison to control predators is a common practice. Deviance partitioning also showed an important spatial component in the probability of extinction. Abandoned territories were not randomly distributed; rather, they were aggregated in extinction ‘hotspots’, mainly related to food availability and human pressure. Deviance partitioning turned out to be an useful tool for identifying the relative contribution of a variety of factors - and their combined effects - associated with an extinction process. The deviance explained by each factor must be interpreted, however, in the context of a good knowledge of the life history of the species. Hierarchical partitioning can help rank conservation priorities and, by using as an objective criterion the relative weight of each independent variable that could be effectively managed for conservation, may provide wildlife managers with a means of saving funds and optimizing action plans. 相似文献
129.
OBJECTIVE: To analyse the alcohol consumption behaviour of the German adult population, with a focus on the characteristics of persons drinking more than the tolerable upper alcohol intake level (TUAL) of 10-12 g day(-1) for healthy adult women and 20-24 g day(-1) for healthy adult men. DESIGN AND SETTING: For the German National Health Interview and Examination Survey 1998, a representative sample of free-living adults was drawn. A total of 7124 participants were interviewed comprehensively about their sociodemographic background, lifestyle and eating habits including alcohol consumption. SUBJECTS: A sub-sample of 4030 women and men, 18-79 years old, who were involved in the integrated German Nutrition Survey. RESULTS: About 16% of women and 31% of men had mean alcohol consumption above the TUAL. Among other factors, the inclination to exceed the TUAL was related to middle-age, high socio-economic status, smoking and use of soft drugs. Among both women and men, a high proportion of persons drinking above the TUAL was observed among those consuming low amounts of soft drinks, fruit, poultry, milk products, bread and cake/biscuits. Women preferred to drink wine, whereas men preferred to drink beer. CONCLUSIONS: Many Germans have an alcohol consumption level above the TUAL and thus are supposed to be at increased risk for alcohol-associated diseases. 相似文献
130.
The assessment of sediment screening risk in Venice Lagoon and other coastal areas using international sediment quality guidelines 总被引:3,自引:0,他引:3
Sabine E. Apitz Andrea Barbanti Alberto Giulio Bernstein Martina Bocci Eugenia Delaney Laura Montobbio 《Journal of Soils and Sediments》2007,7(5):326-341
Background, Aims and Scope A number of studies carried out in recent years have shown the presence of a wide range of contaminants in the Venice Lagoon.
It is important to have a good understanding of the ecological quality of Venice Lagoon sediments, in order to: i) define
and locate areas where a threat to the environment is present and therefore an intervention is needed (i.e. in situ assessment and management); and ii) define sustainable and environmentally correct ways of managing sediments which are to
be dredged for navigational purposes or in relation to other interventions (i.e., ex situ management).
Methods To examine how various regional and international SQGs ‘classed’ screening risk in Venice Lagoon sediments, data on median
contaminant levels in surface sediments in Venice Lagoon resulting from a literature review were compared to a range of local
and international sediment quality guidelines (SQGs). Then data on sediment contaminant levels in various areas and sub-basins
of Venice Lagoon (main Lagoon, Porto Marghera and Venice City Canals) and in other regional and international transitional
and coastal ecosystems with various levels of human impact (urbanization and industrialization) were evaluated based upon
a selected consensus-based SQG. Finally, screening sediment quality for all of Venice Lagoon was mapped and contoured, relative
to this consensus-based SQG and briefly compared with direct toxicity measurement through a battery of bioassays.
Results SQGs allow the sediment areas to be put in terms of potential, or screening, risk. Although there were some differences depending
upon which specific SQGs were applied, the Venice SQGs and other international SQGs provided the same general picture of screening
risk in Venice Lagoon despite geographic differences. Venice Lagoon South has the lowest screening risk levels, Venice Lagoon
Central/North has the highest (and is nearest to the Porto Marghera and Venice City Canals sites).
Discussion The Venice Lagoon sediments have hazard quotients on the low end of the range of moderately urbanized and industrialized sites
and higher than background case studies reviewed. Hg levels in the Venice Lagoon were generally higher than equivalent sites,
while other contaminants were either equivalent or lower. In Porto Marghera (PM) and Venice City Canals (VC), for many contaminants
of interest, PM, and for some, VC sediments have the highest levels of any case study reviewed. Ranges are high, so in all
cases, remedial or disposal decisions should be based upon site-specific (and preferably tiered) data.
Conclusions The use of hazard quotients makes it possible to compare screening risks due to different mixes of contaminants within and
between sites, but results should be interpreted with caution. How these sites rank when compared to some of the other highly
industrialized sites depends upon how data are synthesized and communicated. Actual risk must be evaluated using a weight
of evidence (WOE) approach, as site-specific bioavailability and background levels will differ both regionally and internationally.
Recommendations and Perspectives Whilst there are subtle differences, the current Venice sediment classifications (A, B and C) ‘performed’ in a similar manner
to SQGs in similar classes, suggesting that regions of Venice Lagoon would not be classified much differently if other SQGs
such as TEL, ERL, PEL, ERM or AET were adopted. The Italian sediment quality objectives, on the other hand, are significantly
more conservative than any other SQGs examined, with the exception of the Flemish Reference values. A number of European nations
are considering criteria based upon contaminant levels in relatively pristine modern sites, or based upon derivations of historical
(pre-anthropogenic) contaminant levels. When used as a standard, such an approach lacks discriminating power, designating
almost all sediments within an urbanized or industrialized region as of concern, or even, in many cases, mandating action
or prohibiting various management approaches in a large percentage of sediments. While generally based upon the laudable desire
to return sites to unimpacted levels, there is a risk that overprotective criteria have the opposite effect: by designating
too large a percentage of sediments as requiring management or control, limited resources may be improperly allocated. Which
set of SQGs is most ‘appropriate’ for the Venice Lagoon sediments depends upon the questions being asked. However, the Venice
classifications are currently being used as pass-fail criteria, without consideration of site-specific conditions. The fact
that they performed similarly to SQGs in similar classes suggests that any work to develop more site-specific SQGs (with the
same general decision classes) would probably not make much difference in how sediments were ultimately classified and managed
unless the fundamental approach was changed from a pass-fail to a tiered and WOE approach integrated in a comprehensive decision
framework. For Venice Lagoon, and for other regions, although SQGs should be developed with care, in a scientifically defensible
and risk-based manner, an equally or more important issue to be addressed is their role in overall decision frameworks.
ESS-Submission Editor: Dr. Marc Babut (marc.babut@cemagref.fr) 相似文献