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311.
The IUCN is the leading authority on assessing species’ extinction risks worldwide and introduced the use of quantitative criteria for the compilation of Red Lists of threatened species. Recently, we assessed the threat status of the 483 European butterfly species, using semi-quantitative data on changes in distribution and in population sizes provided by national butterfly experts. We corrected distribution trends for the observation that coarse-scale grid cells underestimate actual population trends by 35%. To account for uncertainty, we included a 5% error margin on the distribution and population trends provided. The new Red List of European butterflies determined one species as Regionally Extinct, 37 species as threatened (Critically Endangered, Endangered or Vulnerable) and a further 44 as Near Threatened. The use of semi-quantitative data on distribution and population trends permitted us to use IUCN criteria to compile a scientifically underpinned Red List of butterflies in Europe. However, a comparison of detailed monitoring data for some grassland species showed that coarse-scale grid cell data and population trends strongly underestimate extinction risks, and the list should be taken as a conservative estimate of threat. Finally, combining the new Red List status with the data provided by the national butterfly experts, allowed us to determine simple criteria to delineate conservation priorities for butterflies in Europe, so called SPecies of European conservation Concern (SPEC’s). Using European butterflies, our approach illustrated how Red Listing can be performed when data are incomplete for some IUCN criteria or vary strongly among countries.  相似文献   
312.
Post-weaning multi-systemic wasting syndrome (PMWS) causes major economic losses for the English pig industry and severity of clinical signs and economic impact vary considerably between affected farms. We present here a novel approach to quantify severity of PMWS based on morbidity and mortality data and presence of porcine circovirus type 2 (PCV2). In 2008-2009, 147 pig farms across England, non-vaccinating for PCV2, were enrolled in a cross-sectional study. Factor analysis was used to generate variables representing biologically meaningful aspects of variation among qualitative and quantitative morbidity variables. Together with other known variables linked to PMWS, the resulting factors were included in a principal component analysis (PCA) to derive an algorithm for PMWS severity. Factor analysis resulted in two factors: Morbidity Factor 1 (MF1) representing mainly weaner and grower morbidity, and Morbidity Factor 2 (MF2) which mainly reflects variation in finisher morbidity. This indicates that farms either had high morbidity mainly in weaners/growers or mainly in finishers. Subsequent PCA resulted in the extraction of one component representing variation in MF1, post-weaning mortality and percentage of PCV2 PCR positive animals. Component scores were normalised to a value range from 0 to 10 and farms classified into: non or slightly affected farms with a score <4, moderately affected farms with scores 4-6.5 and highly affected farms with a score >6.5. The identified farm level PMWS severities will be used to identify risk factors related to these, to assess the efficacy of PCV2 vaccination and investigating the economic impact of potential control measures.  相似文献   
313.
The objective of the present study was to compare two commercially available blood-based pregnancy tests, namely BioPRYN, an ELISA for pregnancy-specific protein B (PSPB), and an ELISA for pregnancy-associated glycoprotein (PAG), for early pregnancy diagnosis in dairy cattle using transrectal ultrasonography as a gold standard. Transrectal ultrasonography was conducted 26-58 days after artificial insemination (AI) in 197 cattle from 19 farms. Concurrently, a blood sample was collected for determination of serum PSPB and PAG. Transrectal palpation was performed approximately 120 days after AI to verify that pregnancy was maintained. For PSPB and PAG, there were no significant differences (P>0.05) in sensitivity (98.0 and 97.8%), specificity (97.1 and 91.2%), positive predictive values (99.3 and 97.8%), negative predictive values (91.9 and 91.2%) and accuracy (97.8 and 96.4%). In conclusion, the two blood pregnancy assays were equally efficacious and were highly accurate (based on transrectal ultrasonography as the gold standard).  相似文献   
314.
Follicle-like structures are three-dimensional matrices joint with living cells that allow the in vitro development of female gametes in more physiological conditions. They have been shown to be beneficial to fresh oocytes in different species, and in this study, domestic cat (Felis silvestris catus) granulosa cells were used to create a functional follicle-like structure aimed at supporting the in vitro maturation of conspecific vitrified oocytes, key players of fertility preservation programmes that usually struggle to acquire their full developmental competence after warming. Cat granulosa cells were cultured for up to 6 days in three-dimensional barium alginate microcapsules (i.e. follicle-like structures) or in two-dimensional monolayers, and their steroidogenic ability (estradiol and progesterone secretion) was assessed to confirm their functionality. The same systems were used (on day 2 or 6 of granulosa cells culture) for the in vitro maturation (IVM) of Cryotop® vitrified immature cat oocytes and compared with microdrops of IVM medium without cells (control). Granulosa cells were able to maintain their functionality in vitro in both the conditions, even if with a different extent of hormonal secretion along culture (p = .02). Vitrified oocytes resumed meiosis at higher rates when cultured with 2 days old granulosa cells (p = .03), but full maturation rates slightly raised when granulosa cells were cultured longer, albeit without differences with the control group. This study paved the road for the creation of enriched culture systems in the domestic cat, but innovations are strongly needed for vitrified oocytes that deserve better chances to develop in vitro.  相似文献   
315.
Buffalo breeding is common in Southern Italy. Dystocia compromises dam's and newborn health and welfare. Difficult parturition could be solved through prompt calving assistance, even if the identification of the beginning of delivery is challenging. Herein, we aimed to evaluate a remote calving alarm system in 15 Mediterranean buffalo heifers. An intravaginal probe was placed close to the external cervical os once premonitory signs of delivery were observed. No vaginal discharge nor signs of discomfort were notified in the days following the insertion of the probe. Heifers calved from 48 to 72 hr after the alarm was activated. The system correctly warned the farm personnel at the beginning of stage II of parturition, except for 2 cases. In the former, the intravaginal probe was expelled but the poor carrier network coverage negatively affected phone's signal quality; in the latter, recurrent vaginal prolapse was responsible for non-retention of the probe. Overall median expulsive phase was 68 ± 8 min, while the expulsion of a female calf took 54 ± 22.0 min and 90 ± 34.0 min in males, with significant difference (p =.02). Deliveries were homogeneously distributed across a 24-hr interval. No retention of foetal membranes nor metritis was identified at postpartum clinical examination. The calving alarm system used in this work was well tolerated in buffalo heifers. The introduction of smart technology in buffalo farming could contribute to the overall farm net return by reducing calf losses, especially for calves born from sexed-sorted semen, and by increasing animal welfare through quick resolution of dystocia. Further studies will be necessary to evaluate the net return in buffalo farms which will implement a remote calving alarm system on a wider population.  相似文献   
316.
Red yeasts of the genus Rhodotorula are of great interest to the biotechnological industry due to their ability to produce valuable natural products, such as lipids and carotenoids with potential applications as surfactants, food additives, and pharmaceuticals. Herein, we explored the biosynthetic potential of R. mucilaginosa 50-3-19/20B collected from the Mid-Atlantic Ridge using modern genomics and untargeted metabolomics tools. R. mucilaginosa 50-3-19/20B exhibited anticancer activity when grown on PDA medium, while antimicrobial activity was observed when cultured on WSP-30 medium. Applying the bioactive molecular networking approach, the anticancer activity was linked to glycolipids, namely polyol esters of fatty acid (PEFA) derivatives. We purified four PEFAs (1–4) and the known methyl-2-hydroxy-3-(1H-indol-2-yl)propanoate (5). Their structures were deduced from NMR and HR-MS/MS spectra, but 1–5 showed no anticancer activity in their pure form. Illumina-based genome sequencing, de novo assembly and standard biosynthetic gene cluster (BGC) analyses were used to illustrate key components of the PEFA biosynthetic pathway. The fatty acid producing BGC3 was identified to be capable of producing precursors of PEFAs. Some Rhodotorula strains are able to convert inulin into high-yielding PEFA and cell lipid using a native exo-inulinase enzyme. The genomic locus for an exo-inulinase enzyme (g1629.t1), which plays an instrumental role in the PEFA production via the mannitol biosynthesis pathway, was identified. This is the first untargeted metabolomics study on R. mucilaginosa providing new genomic insights into PEFA biosynthesis.  相似文献   
317.
Soil texture is one of the main factors controlling soil organic carbon (SOC) storage. Accurate soil‐texture analysis is costly and time‐consuming. Therefore, the clay content is frequently not determined within the scope of regional and plot‐scale studies with high sample numbers. Yet it is well known that the clay content strongly affects soil water content. The objective of our study was to evaluate if the clay content can be estimated by a simple and fast measure like the water content of air‐dried soil. The soil samples used for this study originated from four different European regions (Hainich‐Dün, Germany; Schwäbische Alb, Germany; Hesse, France; Bugac, Hungary) and were collected from topsoils and subsoils in forests, grasslands, and croplands. Clay content, water content of air‐dried soil, and SOC content were measured. Clay content was determined either by the Pipette method or by the Sedigraph method. The water content of air‐dried soil samples ranged from 2.8 g kg–1 to 63.3 g kg–1 and the corresponding clay contents from 60.0 g kg–1 to 815.7 g kg–1. A significant linear relationship was found between clay content and water content. The scaled mean absolute error (SMAE) of the clay estimation from the water content of air‐dried soil was 20% for the dataset using the Pipette method and 28% for the Sedigraph method. The estimation of the clay content was more accurate in fine‐textured than in coarse‐textured soils. In this study, organic‐C content played a subordinate role next to the clay content in explaining the variance of the water content. The water retention of coarse‐textured soils was more sensitive to the amount of organic C than that of fine‐textured soils. The results indicate that in our study the water content of air‐dried soil samples was a good quantitative proxy of clay contents, especially useful for fine‐textured soils.  相似文献   
318.
ObjectiveTo determine the needle‐to‐nerve distances during electrical nerve location in dogs at different currents and pulse duration using a peripheral nerve stimulator (PNS) under ultrasound control (US), and the minimal electrical thresholds (MET) necessary to obtain a motor response (MR) after achieving needle‐to‐nerve contact.Study designProspective in vivo experimental trial in a clinical settingAnimalsThirty dogs, scheduled for locoregional anaesthesia of the sciatic nerve.MethodsNeedle‐to‐nerve distance was measured ultrasonographically after obtaining the MR of sciatic nerve with 2, 1 and 0.5 mA and pulse duration 0.1 ms (NS0.1). Thereafter the needle was placed in contact with the nerve and MET was determined. The procedure was repeated with 0.3 ms (NS0.3). Finally the needle was reintroduced to contact the sciatic nerve guided only by US, thus MET‐US was determined. Data were analysed using Kruskal–Wallis or Mann–Whitney tests.ResultsNeedle‐to‐nerve distances were greater when MR was obtained with 2 mA than with 1 and 0.5 mA at 0.1 and 0.3 ms. No significant differences were observed between the needle‐to‐nerve distances using 0.1 or 0.3 ms.The MET [median (range)] was 0.4 (0.18–1.3) mA in NS0.1, 0.32 (0.12–0.8) mA in NS0.3; while MET‐US was 0.7 (0.32–1.5) mA. When the needle contacted the nerve, the MR achieved with currents below 0.3 mA was obtained in 17.2, 40 and 0% of cases using NS0.1, NS0.3 and US respectively.Conclusions and clinical relevanceThe electrical current necessary to obtain a MR decreased as the needle moved towards the nerve. However when the needle tip contacted the nerve, an MR with low current intensity could not be obtained. Thus the absence of motor response at currents below 0.3 mA cannot rule out needle‐epineurium contact. When ultrasound is combined with PNS, it is more important to assess the correct needle position than searching for an MR at low currents.  相似文献   
319.
HistoryTwo cats were presented for orthopaedic surgery.Physical ExaminationWith the exception of the orthopaedic injuries found, clinical examination showed no abnormality.ManagementAs part of anaesthetic management, one cat received intrathecal morphine, the other epidural morphine. Following recovery, intense grooming was observed. After ensuring adequate analgesia this behaviour was interpreted as pruritus.In the first cat, pruritus was initially managed with medetomidine constant rate infusion (CRI) at 1 and 1.5 μg kg?1 hour?1. The lower dose produced sedation and no relief from pruritus, the higher dose ablated pruritus but induced sedation. Two propofol (lipid emulsion formulation) boli of 0.1 mg kg?1 ablated pruritus without causing sedation. The second cat was successfully treated with four boli of 0.1 mg kg?1 propofol over 20 minutes.Follow–upFollowing treatment with propofol, pruritus did not recur in either cat and both were discharged from the hospital.ConclusionsThis is the first clinical report of morphine–induced pruritus in cats and management with low–dose propofol. These cases suggest an antipruritic mechanism for lipid–formulation propofol.  相似文献   
320.
The potato brown rot, caused by the bacterium Ralstonia solanacearum biovar 2/race 3 (potato race) was classified as quarantine pathogen by the European Union (EU) due to the risks it would pose for the cultivation of potatoes and tomatoes. Quarantine regulations stipulate control surveys and tests on potatoes used as seed, for food as well as industrial purposes and in surface water to check for contamination with R. solanacearum. Toward this end, the Institute for Plant Protection of the Bavarian State Research Center for Agriculture has been conducting an intensive survey for the presence of the potato brown rot pathogen in Bavarian rivers since 1997. An important component of this monitoring is the testing of potential weed hosts growing near river banks. Every year, from June to September, water- and plant samples have been collected from rivers in potato cultivation areas and near potato processing plants. Since the start of the survey, a total of 70 rivers has been tested. The presence of the pathogen was checked by immunofluorescence antibody staining (IFAS) and polymerase chain reaction (PCR). Positive IFAS or PCR tests were checked again by biotests and pathogenicity tests on eggplant (Solanum melongena). So far R. solanacearum could be found in nine Bavarian rivers. Concerning wild plants growing near the river banks the bacterium could be isolated only from roots of the bittersweet nightshade (Solanum dulcamara). However, from stinging nettle (Urtica dioica), nodding beggartick (Bidens cernua), black nightshade (Solanum nigrum), great yellowcress (Rorippa amphibia) and gipsywort (Lycopus europaeus) R. solanacearum could not be isolated. In contaminated rivers, with S. dulcamara growing on the river banks, R. solanacearum could be detected repetitively for several years. In 1997 it was found that rivers can be contaminated by the pathogen, if insufficiently treated sewage from potato processing plants is released into waterways. Potato cultivation is threatened by surface water only, if contaminated water is used to irrigate potato fields. Consequently, surface water should never be used for irrigation of potato fields or application of plant protection products.  相似文献   
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