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71.
BACKGROUND: Laboratory results of the French ANPP/CEB guideline No. 167 and IOBC/WPRS Ring Testing Group methods for testing the side effects of pesticides on the predatory mite Typhlodromus pyri Scheuten were compared with respect to their suitability to evaluate the toxicity of three pesticides. RESULTS: Results obtained with the ANPP/CEB guideline allow the demonstration of significant differences between two slightly toxic products, a dichlofluanid 500 g kg(-1) kWP (Euparen) 50WP) and a quinoxyfen 250 g L(-1) SCC (Legend), and a highly toxic cymoxanil 60/mancozeb 200/folpet 275 g kg(-1) WP [Remiltine F Pepite) (RFP)], on the basis of bioassays conducted in the laboratory. In contrast, results obtained with the IOBC/WPRS method classified all three as harmful.CONCLUSION: The evaluation of the toxicity of RFP revealed that the concentration, the quantity of the wet deposit and the food source used in the IOBC/WPRS method maximise the toxicity, in comparison with those used in the ANPP/CEB protocol. Valid criteria in controls were all respected in the ANPP/CEB tests but not in the IOBC/WPRS samples. This result revealed difficulties related to the use of the IOBC/WPRS method in laboratories. 相似文献
72.
Lin Teng Shee F Arul J Brunet S Mateescu AM Bazinet L 《Journal of agricultural and food chemistry》2006,54(18):6760-6764
Chitosan, a partially deacetylated derivative of chitin, was solubilized by bipolar membrane electroacidification (BMEA). Bipolar/monopolar (anionic or cationic) configuration and chitosan addition mode (single step or stepwise) were examined. Chitosan solubility and electroacidification parameters were monitored during the process to determine the optimal conditions. Bipolar/anionic configuration and stepwise feeding mode led to chitosan solubilization yield of 91% in 60 min at 20 mA/cm(2). In this configuration, chitosan solution had a pH of 2.5, a conductivity of 8.5 mS/cm, and an ash content of 0.2%. Relative energy consumption was 0.05 kWh/L of 1% chitosan solution prepared. Although some chitosan particles were aggregated in the electrodialysis stack, limiting chitosan solubilization, BMEA allowed complete solubilization of chitosan circulating in the system. 相似文献
73.
Mathieu M Motte S Ray L Pensis A Jespers P Brimioulle S Laroute V Naeije R Mc Entee K 《American journal of veterinary research》2006,67(7):1236-1243
OBJECTIVE: To investigate the effects of preventive angiotensin converting enzyme inhibitor treatment with ramipril in dogs with progressively severe experimentally induced heart failure. ANIMALS: 20 dogs. PROCEDURES: Dogs were randomly allocated to receive no treatment (control) or ramipril (0.125 mg/kg, PO, daily) for 7 weeks. Physical examination, repetitive catheterization of the right side of the heart, and echocardiography were performed before the study (day 0) and weekly for 7 weeks. Renal plasma flow (RPF) as determined by para-aminohippuric acid clearance and glomerular filtration rate (GFR) as determined by creatinine and iohexol clearances were measured on day 0 and at weeks 4 and 7. RESULTS: Overpacing induced a progressive increase in right atrial pressure (RAP) and pulmonary artery pressure, occluded (PAPO), with a decrease in systemic arterial pressure. There were progressive alterations of echocardiographic indices of diastolic and systolic ventricular function. The RPF and GFR decreased before cardiac output decreased, and filtration fraction increased. The logarithm of the urinary sodium-to-potassium concentration ratio (log(10)[Na(+)/K(+)]) decreased. Significant effects of ramipril included a delay in clinical signs of heart failure, a late decrease in RAP and PAPO, and increases in the sodium excretion fraction and log(10)(Na(+)/K(+)). There was a satisfactory agreement between the creatinine and iohexol clearance measurements. Conclusions AND CLINICAL RELEVANCE: Results suggest that, in this rapid-evolving, dilated cardiomyopathy, activation of the renin-angiotensin system contributes to the pathophysiology of heart failure late in the disease and essentially by an activation of renal salt and water retention. 相似文献
74.
E J Milner‐Gulland Serge Garcia William Arlidge Joseph Bull Anthony Charles Laurent Dagorn Sonya Fordham Joshua Graff Zivin Martin Hall Jeffrey Shrader Niels Vestergaard Chris Wilcox Dale Squires 《Fish and Fisheries》2018,19(3):547-561
In terrestrial and coastal systems, the mitigation hierarchy is widely and increasingly used to guide actions to ensure that no net loss of biodiversity ensues from development. We develop a conceptual model which applies this approach to the mitigation of marine megafauna by‐catch in fisheries, going from defining an overarching goal with an associated quantitative target, through avoidance, minimization, remediation to offsetting. We demonstrate the framework's utility as a tool for structuring thinking and exposing uncertainties. We draw comparisons between debates ongoing in terrestrial situations and in by‐catch mitigation, to show how insights from each could inform the other; these are the hierarchical nature of mitigation, out‐of‐kind offsets, research as an offset, incentivizing implementation of mitigation measures, societal limits and uncertainty. We explore how economic incentives could be used throughout the hierarchy to improve the achievement of by‐catch goals. We conclude by highlighting the importance of clear agreed goals, of thinking beyond single species and individual jurisdictions to account for complex interactions and policy leakage, of taking uncertainty explicitly into account and of thinking creatively about approaches to by‐catch mitigation in order to improve outcomes for conservation and fishers. We suggest that the framework set out here could be helpful in supporting efforts to improve by‐catch mitigation efforts and highlight the need for a full empirical application to substantiate this. 相似文献
75.
Kamga-Waladjo Alain Richi Gbati Oubri Bassa Kone Philippe Lapo Rock Allister Chatagnon Gérard Bakou Serge N. Pangui Louis Joseph Diop Papa El Hassane Akakpo Justin Ayayi Tainturier Daniel 《Tropical animal health and production》2010,42(5):953-959
The aim of this study was to determine the seroprevalence of Neospora caninum antibodies and its effects on reproductive parameters in cows in intensive dairy herds in Dakar. Randomised blood samples
were taken for serology from 196 cows in four herds with a history of sporadic abortion. All of the sera were assayed for
antibodies against N. caninum, Candida guillermondii, Coxiella burnetii, and Chlamydophila sp. The associations between serostatus and reproductive parameters (abortion, number of inseminations to conception, and
calving to conception interval) were assessed over a period of 5 years (2004–2008). The seroprevalence of N. caninum antibodies in dairy cattle was 17.9%. The local Gobra breed and crossbreeds had higher levels of N. caninum antibodies than exotic breeds (p < 0.05). For the most recent pregnancies, seropositive cows required more inseminations to establish conception than seronegative
cows (p < 0.05). The results indicate that dairy cattle from Dakar are exposed to N. caninum. Neosporosis should, therefore, be systematically considered as a cause when the calving to conception interval is prolonged. 相似文献
76.
Syarifah Aisyafaznim Sayed Abdul Rahman Zulqarnain Mohamed Rofina Yasmin Othman Rony Swennen Bart Panis Dirk De Waele Serge Remy Sebastien Christian Carpentier 《European journal of plant pathology / European Foundation for Plant Pathology》2010,128(3):343-351
The polyphagous obligate parasites Meloidogyne spp. devastate a wide range of crop plants including bananas and plantains. Their infestations impact agriculture worldwide. Therefore,
an effective combating regime against this nematode species and an in-depth understanding of plant-nematode interaction are
essential. Early detection of infection by visual inspection is not possible. This hampers early control strategy efforts
and makes in-depth research of the early infection and plant defence unfeasible. A simple and robust in planta PCR-based nematode detection method is described here as the first crucial step. This PCR-based detection assay exploits
the existence of the Internal Transcribed Spacer 1 (ITS 1) region of the ribosomal DNA (rDNA) gene family in the nematodes
for early detection of nematode penetration into the roots. The results demonstrate that this detection assay is suitable
to serve as a molecular screening tool for plant root diagnostic purposes. 相似文献
77.
Delphine?Allorent Serge?SavaryEmail author 《European journal of plant pathology / European Foundation for Plant Pathology》2005,113(4):329-341
In this review, available knowledge on angular leaf spot (ALS) of bean, caused by Phaeoisariopsis griseola, is analysed and synthesised. This is done through a systems-analytical approach, and successive flowcharts of the system,
in order to identify knowledge gaps and guide further research. Six connected sub-models of the ALS monocycle are used as
a framework: lesion establishment, lesion extension, defoliation, sporulation, spore liberation, and spore deposition. Each
of the sub-models enables the linking of processes to various effects of environmental (physical and host) factors. Disease-induced
defoliation is one feature of the pathosystem, leading to a depletion of infectious tissues from the canopy, which are transferred
to the ground. Consequences of defoliation may include: strong reductions of the amount of inoculum and of vacant sites in
the canopy, limited maximum disease severity, and progressive accumulation of inoculum below the canopy, which may become
important a later stage of disease epidemics. These elements are hypothesised to explain the typical behaviour of ALS epidemics
in the field, especially late onset, high apparent rate of disease increase, and low level of terminal disease severity in
the standing canopy. Epidemiological consequences of lesion expansion, sporulation, and survival of spores deposited onto
the canopy are other knowledge gaps in this pathosystem. 相似文献
78.
Pathological and microbiological observations made on spontaneous cases of acute neonatal calf diarrhea. 总被引:15,自引:4,他引:15 下载免费PDF全文
The purpose of this report is to describe clinical signs, gross and microscopic lesions, bacteriological and immunofluorescence observations made on spontaneous cases of acute neonatal calf diarrhea (NCD) in dairy and beef herds. The following diagnostic tools were used: 1) direct smears of intestinal content, 2) Escherichia coli counts, 3) aerobic bacterial cultures of the small intestine and other organs (The O serogroup and the enterotoxigenicity of the E. coli isolated was determined), 4) detection of the two Nebraska NCD viruses (reo-like and corona-like) by the fluorescent antibody technique and 5) histological examination on different segments of the digestive tract. The following etiological diagnoses were suggested after post mortem examination of 55 cases of NDC (34 were submitted alive): reo-like virus only (1), reo-like virus + E. coli (4), reo-like virus + cryptosporidium (2), reo- + corona-like viruses (5), reo- + corona-like viruses + cryptosporidium (3), reo- + corona-like viruses + infectious bovine rhinotracheitis virus (1), coronavirus-like agent only (2), coronavirus-like agent + mycotic abomasitis (1), coronavirus-like agent + crytosporidium (1), E. coli only (6), cryptosporidium only (5), mycotic abomasitis (3), mycotic rumenitis + reticulitis (1) and undetermined (20). Most of the calves in the last group were submitted dead. 相似文献
79.
Sophie Radacovici R al Lallier Serge Larivi re J. Daniel Dubreuil 《Veterinary microbiology》1992,30(4):369-385
A saline extract of boiled-formalinized whole cells from a local strain (81–750; Quebec, Canada) of Actinobacillus pleuropneumoniae, serotype 5b was used as an antigen in an enzyme-linked immunosorbent assay (ELISA) for serodiagnosis of swine pleuropneumonia. Characterization of this crude extract was done and proteins, neutral sugars, hexosamines, and 2-keto-3-deoxyoctonate (KDO) were evaluated. On phenol extraction of the crude extract a serotype-specific antigen of polysaccharidic nature was recovered from the aqueous phase. This antigen was characterized using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) with Coomassie blue, silver and Schiff stainings. Immunoblots were done using sera of experimentally infected pigs that showed serotype specificity and cross-reactivity. Overall, the results indicate that the O-chain of lipopolysaccharides is a specific antigen that could be used in ELISA for the serodiagnosis of serotype 5 of A. pleuropneumoniae. 相似文献
80.