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71.
Alexandra J. Tomlinson Annie Rayner Ashleigh Bright David P. Cowan Kate E. Littin Ruth Layton 《国际虫害防治杂志》2018,64(3):271-278
Anticoagulant rodenticides (ARs) are considered inhumane, show increasingly limited efficacy due to acquired resistance, and carry environmental consequences associated with non-target species uptake. In a questionnaire study of 499 UK farms that all deployed chemical rodenticide we found a high mean reliance (79%), on second generation ARs with just over half of the respondents using no other rodent control methods. Additional methods where deployed, alone or in combination, included predation (41%), kill-trap deployment (16%) and shooting (1%). Nearly 40% of all respondents deployed rodenticides year-round. There was no evidence to suggest that “tidy-farm” measures, such as clearing food spills and minimising on-farm rodent harbourage sites aimed at minimising rodent-associated problems, were associated with a lower likelihood of year-round deployment; in fact trends in our analyses suggested the opposite. We therefore encourage operators to fully evaluate the true necessity of rodenticide deployment before AR use. 相似文献
72.
Potatoes require high nitrogen (N) fertilizer rates because of their poor N efficiency. Better understanding of N dynamic in potato crops could improve N efficiency and thus enhance crop profitability and reduce N losses. A similar field experiment was conducted in Switzerland in 3 years, from 2009 to 2011, to investigate the yield and quality response to N fertilization of two commercial potato cultivars with different tuber qualities, Bintje and Laura. Five doses of ammonium nitrate were tested: 0, 80, 120, 160 and 200 kg N ha?1. Aboveground and belowground biomass evolution, total yield, starch concentration and tuber sizes were measured annually. In 2011, the total N uptake and the soil mineral N content were also measured during the growing season and at harvest.The study showed that N fertilization had a positive effect on yield and the percentage of large tubers (>?70 mm) and a negative effect on starch concentration. Both cultivars presented the same potential yield, although cv. Laura’s yield was more affected by N fertilization deficiency and more responsive to the late N fertilizer application. At harvest, both cultivars had a similar N uptake efficiency and N utilization efficiency. However, they differed with respect to N uptake dynamics. Nitrogen uptake was slower for cv. Laura than for cv. Bintje due to a longer period required for the development of the belowground biomass. The results provide useful recommendations for improvement of N fertilization practices (e.g. rate and time of application) of these two cultivars in Swiss conditions. 相似文献
73.
Pesticide exposure assessment for surface waters in the EU. Part 1: Some comments on the current procedure 下载免费PDF全文
Martin Bach Mirjam Diesner Dietlinde Großmann Djamal Guerniche Udo Hommen Michael Klein Roland Kubiak Alexandra Müller Jan Priegnitz Kai Thomas Matthias Trapp 《Pest management science》2016,72(7):1279-1284
In 2001, the European Commission introduced a risk assessment project known as FOCUS (FOrum for the Coordination of pesticide fate models and their USe) for the surface water risk assessment of active substances in the European Union. Even for the national authorisation of plant protection products (PPPs), the vast majority of EU member states still refer to the four runoff and six drainage scenarios selected by the FOCUS Surface Water Workgroup. However, our study, as well as the European Food Safety Authority (EFSA), has stated the need for various improvements. Current developments in pesticide exposure assessment mainly relate to two processes. Firstly, predicted environmental concentrations (PECs) of pesticides are calculated by introducing model input variables such as weather conditions, soil properties and substance fate parameters that have a probabilistic nature. Secondly, spatially distributed PECs for soil–climate scenarios are derived on the basis of an analysis of geodata. Such approaches facilitate the calculation of a spatiotemporal cumulative distribution function (CDF) of PECs for a given area of interest and are subsequently used to determine an exposure concentration endpoint as a given percentile of the CDF. For national PPP authorisation, we propose that, in the future, exposure endpoints should be determined from the overall known statistical PEC population for an area of interest, and derived for soil and climate conditions specific to the particular member state. © 2016 Society of Chemical Industry 相似文献
74.
75.
Geoffroy de la Rebière de Pouyade DVM MSc ; Sigrid Grulke DVM PhD DECVS ; Johann Detilleux DVM MSc PhD DECVPH ; Alexandra Salciccia DVM MSc ; Denis R. Verwilghen DVM MSc ; Isabelle Caudron DVM PhD DECVS ; Monika Gangl MV MSc DECVS Didier D.A. Serteyn DVM PhD DECVA 《Journal of Veterinary Emergency and Critical Care》2009,19(1):113-119
Objectives – The aim of this study is to describe the prevalence of postoperative laminitis in colic cases and to determine if low-molecular-weight heparin (LMWH) is effective in preventing this complication.
Design – Retrospective clinical study.
Animals – Client-owned horses.
Interventions – SC administration of enoxaparin during the postoperative period.
Measurements and Main Results – Medical records of 360 horses undergoing surgery for colic and surviving at least 3 days were evaluated. Fifty-six horses admitted before 1995 did not receive LMWH (control group) and 304 admitted after 1995 received LMWH as a prophylaxis for laminitis (treatment group). Three grades of severity were defined for laminitis. Prevalence and severity of laminitis were compared between the 2 groups. Several parameters recorded on admission (sex, age, breed, site and nature of the disease, heart rate, PCV, gravity score, and shock score) and the administration of LMWH were tested as risk factors in the development of laminitis in a logistic regression procedure. Prevalence and grade of laminitis were significantly lower in the treatment group. Only the absence of LMWH was recognized as a significant risk factor in the logistic regression model.
Conclusions – The administration of LMWH appears to be effective in the prophylaxis of laminitis following colic surgery and may be useful in the postoperative management of these horses. 相似文献
Design – Retrospective clinical study.
Animals – Client-owned horses.
Interventions – SC administration of enoxaparin during the postoperative period.
Measurements and Main Results – Medical records of 360 horses undergoing surgery for colic and surviving at least 3 days were evaluated. Fifty-six horses admitted before 1995 did not receive LMWH (control group) and 304 admitted after 1995 received LMWH as a prophylaxis for laminitis (treatment group). Three grades of severity were defined for laminitis. Prevalence and severity of laminitis were compared between the 2 groups. Several parameters recorded on admission (sex, age, breed, site and nature of the disease, heart rate, PCV, gravity score, and shock score) and the administration of LMWH were tested as risk factors in the development of laminitis in a logistic regression procedure. Prevalence and grade of laminitis were significantly lower in the treatment group. Only the absence of LMWH was recognized as a significant risk factor in the logistic regression model.
Conclusions – The administration of LMWH appears to be effective in the prophylaxis of laminitis following colic surgery and may be useful in the postoperative management of these horses. 相似文献
76.
Nicola Grint BVSc DVA Diplomate ECVAA MRCVS & Alexandra Dugdale MA Vet MB DVA Diplomate ECVAA MRCVS 《Veterinary anaesthesia and analgesia》2009,36(1):63-66
Objective To compare the brightness of South American camelid venous blood to that of Equidae.
Study design Prospective clinical evaluation.
Animals Twelve South American camelids (eight llamas, four alpacas), eight horses and ponies (control group).
Methods Appropriately sized catheters were placed in the jugular vein of each animal under local anaesthesia. The blood spilt before the catheter was capped was caught on a white tile. A sample of blood was drawn for blood-gas analysis. The brightness of the blood (both on the tile and in the syringe) was matched to a colour chart (1 = darkest red, 8 = brightest red) by a single observer under bright light conditions. Packed cell volume (PCV) and partial pressure of oxygen (PvO2 ) in the blood were also measured on the syringe blood. Normally distributed data were compared using a two tailed t -test, and non-normally distributed data were compared using a Mann–Whitney U -test. Significance was set at p < 0.05.
Results Camelid venous blood was significantly brighter red than that of horses and ponies both on the white tile ( p = 0.0003) and in the syringe ( p = 0.0001). PCV was significantly lower in camelids (32 ± 4%) compared with horses (37 ± 5%). Partial pressure of oxygen values were similar between groups.
Conclusions and clinical relevance Jugular venous blood in alpacas and llamas is significantly brighter red than that of horses. Colour should not be used as a sole determinant of venous or arterial catheterization in this species. 相似文献
Study design Prospective clinical evaluation.
Animals Twelve South American camelids (eight llamas, four alpacas), eight horses and ponies (control group).
Methods Appropriately sized catheters were placed in the jugular vein of each animal under local anaesthesia. The blood spilt before the catheter was capped was caught on a white tile. A sample of blood was drawn for blood-gas analysis. The brightness of the blood (both on the tile and in the syringe) was matched to a colour chart (1 = darkest red, 8 = brightest red) by a single observer under bright light conditions. Packed cell volume (PCV) and partial pressure of oxygen (PvO
Results Camelid venous blood was significantly brighter red than that of horses and ponies both on the white tile ( p = 0.0003) and in the syringe ( p = 0.0001). PCV was significantly lower in camelids (32 ± 4%) compared with horses (37 ± 5%). Partial pressure of oxygen values were similar between groups.
Conclusions and clinical relevance Jugular venous blood in alpacas and llamas is significantly brighter red than that of horses. Colour should not be used as a sole determinant of venous or arterial catheterization in this species. 相似文献
77.
Julie Gombert Frédérik Le Dily Jérémy Lothier Philippe Etienne Laurence Rossato Jean‐Michel Allirand Alexandra Jullien Alexandre Savin Alain Ourry 《植物养料与土壤学杂志》2010,173(6):875-884
In order to optimize nitrogen (N) fertilization and to reduce the environmental impact of oilseed rape without decreasing yield, a clearer understanding of N dynamics inside the plant is crucial. The present investigation therefore aimed to study the effects of different N‐application rates on the dynamics of N uptake, partitioning, and remobilization. The experiment was conducted on winter oilseed rape (Brassica napus L. cv. Capitol) under three levels of N input (0, 100, and 200 kg N ha–1) from stem elongation to maturity using 15N‐labeling technique to distinguish between N uptake and N retranslocation in the plant. Nitrogen fertilization affected the time‐course of N uptake and also the allocation of N taken up from flowering to maturity. Most pod N came from N remobilization, and leaves accounted for the largest source of remobilized N regardless the N‐application rate. However, the contribution of leaves to the remobilized N pool increased with the N dose whereas the one of taproot decreased. Stems were the main sink for remobilized N from stem elongation to flowering. Leaves remained longer on N200 than on N0 and N100 plants, and N concentration in fallen leaves increased with the N treatment and in N100 plants along an axial gradient from the basal to the upper leaves. Overall, these results show that the timing of N supply is more crucial than the N amount to attain a high N efficiency. 相似文献
78.
Encephalitozoon intestinalis infection of sows is reported from a pig farm in Slovakia. Spores were detected by direct microscopic visualisation in the faeces of 25 out of 27 sows (92.6%). This finding was also supported serologically by the presence of specific anti-E. intestinalis antibodies and by a species-specific polymerase chain reaction (PCR). This is the first report on E. intestinalis infection of swine in Europe. 相似文献
79.
Lluvia de Abril Alexandra Soriano-MelgarLilia Alcaraz-Meléndez Lía C. Méndez-RodríguezMaría Esther Puente Fernando Rivera-CabreraTania Zenteno-Savín 《Industrial Crops and Products》2012,37(1):321-327
Damiana (Turnera diffusa Willd) is traditionally used in the elaboration of tea, liquors, in the production of cosmetic products, and as a medicinal plant. The aim of this study was to evaluate the antioxidant content and trace element concentrations in leaves and stems from damiana grown wild and under cultivated conditions in semi-arid zones. Plants were collected at three different sites, two where damiana grows wild and one where it is cultivated for experimental purposes. Significant differences in the concentration of trace elements, vitamin C and total phenolic compound content, as well as antioxidant enzyme activities, total antioxidant capacity, and lipid peroxidation levels were found between leaves and stems, as well as among sampling sites. Environmental conditions, in combination with genetic factors, apparently affect the trace element concentrations, antioxidant content, and total antioxidant capacity in damiana grown wild. Results suggest that nutrient enrichment, via the addition of fertilizers, contributed to increased antioxidant defenses in the cultivated damiana plants. Furthermore, we suggest that genetic selection, controlled environmental conditions, and specific agrotechnical practices can increase the antioxidant yield in leaves and stems of cultivated damiana. 相似文献
80.
Nathalie Chenais Alexandra Depince Pierre-Yves Le Bail Catherine Labbe 《Aquaculture International》2014,22(1):63-76
Domestication is a long-term process during which wild fish are acclimated to farming conditions and hopefully are reproduced over several generations, possibly using selective breeding. Preservation of the genetic diversity of the original population, together with that of the ongoing selection steps, is important for ecological and economical purposes. Cryobanking of reproductive cells is one answer to meet this need. In fish, however, only sperm can be cryopreserved as neither oocytes nor embryos are capable of handling the freeze-thawing stress. In this review, we explore to what extent diploid cells obtained from fin pieces can be used for the preservation of both parental genomes. The main parameters, which should be under control to ensure proper production of fin cells in culture and to enable cryopreservation of the material are described. After cryobanking of such non-reproductive cells, fish can be reconstructed using the nuclear transfer technology whose potentials and difficulties are discussed. The gametes produced by the fish reconstructed after somatic cells nuclear transfer are different to some extent from the gametes obtained after the direct transplantation of primordial germ cell or spermatogonial germ cells into host embryos or larvae. However, in some cases, only somatic cells can be obtained in quantities which would be compatible with strain restoration purposes. From the knowledge available today, it is reasonable to expect that nuclear transfer becomes available for fish reconstruction, even if restricted to high-tech biotechnology facilities. Therefore, cryobanking of fin somatic cells can be farsightedly considered for high-throughput diploid genome conservation. 相似文献