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11.
Bottom trawl fishing is a controversial activity. It yields about a quarter of the world's wild seafood, but also has impacts on the marine environment. Recent advances have quantified and improved understanding of large‐scale impacts of trawling on the seabed. However, such information needs to be coupled with distributions of benthic invertebrates (benthos) to assess whether these populations are being sustained under current trawling regimes. This study collated data from 13 diverse regions of the globe spanning four continents. Within each region, we combined trawl intensity distributions and predicted abundance distributions of benthos groups with impact and recovery parameters for taxonomic classes in a risk assessment model to estimate benthos status. The exposure of 220 predicted benthos‐group distributions to trawling intensity (as swept area ratio) ranged between 0% and 210% (mean = 37%) of abundance. However, benthos status, an indicator of the depleted abundance under chronic trawling pressure as a proportion of untrawled state, ranged between 0.86 and 1 (mean = 0.99), with 78% of benthos groups > 0.95. Mean benthos status was lowest in regions of Europe and Africa, and for taxonomic classes Bivalvia and Gastropoda. Our results demonstrate that while spatial overlap studies can help infer general patterns of potential risk, actual risks cannot be evaluated without using an assessment model that incorporates trawl impact and recovery metrics. These quantitative outputs are essential for sustainability assessments, and together with reference points and thresholds, can help managers ensure use of the marine environment is sustainable under the ecosystem approach to management.  相似文献   
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Emergence of policies dealing with concern over soil degradation and anthropogenic impacts to soil is likely to increase the requirement for assessment of soil quality and identification of soils at risk from degradation. An example is the proposed EU Soil Framework Directive, which features the identification of areas requiring protection from soil degradation. There have been some serious objections to such requirements on the grounds of resource and capital demands. To help to address these concerns, this work proposes a strategic set of indicators based on measured soil quality indicators. These can be used in screening locations to assess the likelihood of degradation and indicate areas for further detailed assessment. This will allow further emphasis to be placed on a smaller number of locations, which could lead to cost and resource efficiencies. Indicators have been used in the past in assessment of soil quality; they are parameters which can be measured and correspond to assessment criteria to measure and help monitor the status and changes. The study reviews the current state of soil quality assessment including methods and indicators that are used to collect data and approaches used to assess data to determine areas subject to soil degradation. Methods and practicalities for data collection and screening are discussed, including the need for further pilot testing and protocol development. Use of public data collection could allow more resource efficient protection of soils, in addition to benefits of public engagement, and raising awareness of the importance of soils and soil biodiversity. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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This study was undertaken to detect pregnancy in Iraqi riverine buffalo (Bubalus bubalis) using three different methods (rectal palpation, plasma progesterone concentration and detection of the presence of pregnancy‐specific protein B (PSPB) with the BioPRYN® enzyme‐linked immunosorbent assay (ELISA) test. The aim of the study was to identify the most sensitive, early and accurate method for detecting pregnancy. Twenty‐two female riverine buffalo that were 6.0 ± 0.93 years old were used. Four blood samples per buffalo were taken via jugular venipuncture at days 22–24, 32–34, 42–44 and 58–61 post‐mating (PM) to measure the progesterone concentration (ng/ml) and to detect the presence of plasma PSPB. The rectal palpation method was employed to evaluate all buffalo on days 42–44 and 58–61 PM. The BioPRYN® test differed (p < 0.01) from the other tests with earlier accuracy for detecting pregnant and non‐pregnant buffalo. Eighty‐eight percent of pregnant and 76.9% of non‐pregnant buffalo were distinguished early (days 22–24 PM) using BioPRYN® and plasma PSPB‐ELISA level (2.09 ± 0.12 ng/ml) in relation to 66.7% and 53.9% detected using the progesterone assay at similar days (4.30 ± 0.40 ng/ml). In conclusion, these results described, for the first time, the early and accurate pregnancy detection of water riverine buffalo using BioPRYN® technology and provided the plasma levels of PSPB using an ELISA test. These findings will improve the reproductive and productive efficiency of Iraqi riverine buffalo by adapting the recent management and reproductive strategies in Iraq and in the world.  相似文献   
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A new, fatal mycotoxicosis of cattle has been recognised in north-western Australia. A feeding trial confirmed the toxicity of a previously unknown species of Corallocytostroma that grows on Mitchell grass (Astrebla spp). The disease has been colloquially named ‘black soil blindness’ because its most prominent features are its confinement to pastures on black soil, and blindness and death of affected animals. Over 500 cattle have died and considerable subclinical disease is present. Above average wet season rainfall and extended growing seasons may explain the emergence of the fungus. The disease is important because cattle production in large areas of Australia utilise Mitchell grass pastures.  相似文献   
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The objective of this study was to evaluate different concentrations of growth hormone (GH) on the development of bovine preantral follicles cultured included in the ovarian tissue (in situ) on the rates of morphologically normal, viable, primordial and developing follicles, as well as the oocyte and follicle diameter and ultrastructural analysis. Ovarian fragments collected from cows with no cross‐breeds defined were cultured in situ for 1 and 7 days in minimal essential medium (α‐MEM+) supplemented with different concentrations of recombinant human GH (0, 10, 25, 50 ng/ml). The ovarian fragments non‐cultured (control) and cultured were processed for classic histology, mechanical isolation and electron transmission microscopy (MET). The parameters underwent anova (Tukey′s and Dunnett′s tests) and chi‐square test (χ2). After 7 days of culture, the treatment with 50 ng/ml GH showed no differences with fresh control (p > 0.05) and had greater effectiveness than in the 0, 10 and 25 ng/ml GH concentrations of the morphologically normal follicles. Regarding the primordial follicles, a reduction was observed in the 50 ng/ml GH concentration concomitant with the significant increase in developing follicles, differing from both the fresh control and the other GH concentrations tested. In addition, 50 ng/ml GH showed a larger follicle and oocyte diameter when compared to the other treatments cultured. Similar structures were ultrastructurally observed in the control group, 50 ng/ml GH. Follicles cultured in 10 ng/ml GH showed nuclear invagination, vacuoles and lesioned basal membrane. Hence, it is concluded that 50 ng/ml GH is the most effective concentration for the development of preantral follicles cultured in situ.  相似文献   
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A 19-year-old, speyed, domestic short-hair cat was presented with an eyelid tumour of 3 months duration. Ophthalmic examination revealed a large, raised, ulcerated and bleeding mass affecting the left lower eyelid. The mass was 12 mm x 10 mm in size, extended to the medial canthus and had eroded 10 mm of eyelid margin. Mandibular lymph nodes were not palpably enlarged. A diagnosis of squamous cell carcinoma was confirmed by histologic examination. Due to involvement of more than half the lower eyelid, it was decided that treatment with radioactive gold-198 seeds was appropriate. Nine radioactive gold-198 seeds were implanted, delivering a minimum tumour dose of 65 Gy. Three weeks postoperatively the mass had resolved, with only a small scab remaining. After a further 3 weeks, there was no evidence of the eyelid tumour. Although approximately 7 mm of eyelid margin was absent, this did not cause any clinical signs other than mild conjunctivitis. There was no evidence of the tumour 10 months postoperatively, when the cat was euthanased for unrelated disease.  相似文献   
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This trial was conducted on a Hungarian dairy farm between July 2001 and December 2004. The objective of this work was to improve the reproductive efficiency with relatively high milk production. At the beginning of this trial blood and fodder samples were taken for checking the metabolic status of the animals in order to determine their health condition. The nutritive value of the daily ration for all groups met with the requirements of the Hungarian National Standard and almost all serum metabolic parameters differed between the milking and pregnant animals. Early pregnancy detection (by ultrasound) and ovulation synchronizing methods were introduced to optimize reproductive performance. The oestrus cycle was also checked by ultrasound and open cows were treated by the appropriate method in order to inseminate them as soon as possible. Efficiency of artificial insemination (AI) followed by a single prostaglandin F2alpha (PGF2alpha) and Ovsynch treatment was similar (30.8% and 29%) and less effective than AI after natural heat detection (37.1%). Provsynch (Pre-synch followed by Ovsynch) was the most effective ovulation synchronization method (conception rate=42.6%; p<0.01). Although milk production increased between 2002 and 2004 by approximately 600 kg per cow, the calving period decreased by 20 days and the number of AIs per pregnancy was also improved (0.8 AI per conception). These findings are really beneficial economically because the decrease in the calving interval returns profit for the dairy farms; one open day costs euro2.5/cow. Economical analysis showed a high profit ratio from the reproductive 'investment' on this farm. Every invested euro yielded approximately euro10.  相似文献   
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