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121.
Ohne ZusammenfassungAnm. d. Schriftl.: Im Interesse der Geschlossenheit der vom Verfasser im Saarland gemachten Beobachtungen und im Hinblick auf den in der Einleitung des Aufsatzes zum Ausdruck gebrachten zielstrebigen Grundgedanken, glauben wir es ausnahmsweise verantworten zu dürfen, den unserer Zeitschrift bewußt gesteckten Rahmen, nur von tierischen Schädlingen zu berichten, in diesem zusammenfassenden Beitrag zu überschreiten.  相似文献   
122.
Fisheries and aquaculture production, imports, exports and equitability of distribution determine the supply of aquatic food to people. Aquatic food security is achieved when a food supply is sufficient, safe, sustainable, shockproof and sound: sufficient, to meet needs and preferences of people; safe, to provide nutritional benefit while posing minimal health risks; sustainable, to provide food now and for future generations; shock‐proof, to provide resilience to shocks in production systems and supply chains; and sound, to meet legal and ethical standards for welfare of animals, people and environment. Here, we present an integrated assessment of these elements of the aquatic food system in the United Kingdom, a system linked to dynamic global networks of producers, processors and markets. Our assessment addresses sufficiency of supply from aquaculture, fisheries and trade; safety of supply given biological, chemical and radiation hazards; social, economic and environmental sustainability of production systems and supply chains; system resilience to social, economic and environmental shocks; welfare of fish, people and environment; and the authenticity of food. Conventionally, these aspects of the food system are not assessed collectively, so information supporting our assessment is widely dispersed. Our assessment reveals trade‐offs and challenges in the food system that are easily overlooked in sectoral analyses of fisheries, aquaculture, health, medicine, human and fish welfare, safety and environment. We highlight potential benefits of an integrated, systematic and ongoing process to assess security of the aquatic food system and to predict impacts of social, economic and environmental change on food supply and demand.  相似文献   
123.
Aloe ferox (Mill), Leonotis leonurus (L) R. BR; and Elephantorrhiza elephantina (Burch.) Skeels are plants frequently used by resource-limited farmers in the Eastern Cape Province to control gastrointestinal parasites in goats. A study was conducted to validate their anthelminthic activities in-vitro on the egg and larvae of the nematode parasite Haemonchus contortus. The crude aqueous extracts of leaves of A. ferox and L. leonurus; and roots of E. elephantina were used. Eggs and larvae of the parasite were incubated at 25°C in aqueous extracts at concentrations of 0.625–20 mg/ml for 48 h and 7 days for the egg hatch and larval development assays respectively. Albendazole and water were the positive and negative controls respectively. Inhibition of egg hatching and larval development increased significantly (P?<?0.05) with increasing concentrations of the extracts. E. elephantina and L. leonurus extracts had 100% egg hatch inhibition at concentration as low as 2.5 mg/ml and 1.25 mg/ml respectively, whereas A. ferox extracts had 100% inhibition at concentrations of 20 mg/ml. At the lowest concentration tested (0.625 mg/ml), E. elephantina inhibited egg hatching >96% and this was comparable to albendazole at the same concentration. E. elephantina and L. leonurus also totally inhibited larval development at concentrations of 1.25 mg/ml. The study provided evidence that A. ferox, E. elephantina and L. leonurus extracts possess anthelminthic activity, thus justifying their use in the treatment of GI helminthosis. There is however need to assess the safety of these plants in vivo and also to undertake in vivo efficacy studies.  相似文献   
124.
The ability to use ciclosporin (Atopica®: Novartis Animal Health, Greensboro, NC, USA) prior to intradermal testing (IDT) would help avoid exacerbation of clinical disease that can be associated with drug withdrawal. This study evaluated the effects of 30 days of administration of ciclosporin at a dose of 5 mg/kg once daily on IDT reactivity (immediate phase reactions) in a group of dogs with atopic dermatitis (AD) with initial positive IDT reactions. 16 dogs diagnosed with AD were included in the study. Eight dogs (group A) were treated with ciclosporin orally at 5 mg/kg once daily for 30 days. Eight dogs (group P) were treated with a placebo orally once daily for 30 days. IDT was performed at day 0 and day 30 on all dogs enrolled using a standardized panel of 45 aqueous allergens (Greer Laboratories, Lenoir, NC, USA) appropriate to our geographical region. IDT reactivity was assessed by both subjective and objective methods at 15 min post‐intradermal injection. Serum for allergen‐specific immunoglobulin (IgE) serology was obtained at day 0 and day 30. The study was designed as a double‐blinded, placebo‐controlled, cross‐over study. Data were analysed using a split‐plot analysis of variance with the grouping factor of treatment and the repeat factor of time (SAS System for Windows). At week 4, ciclosporin did not have a statistically significant effect on IDT reactivity or serology results. It therefore appears that, no withdrawal is recommended to evaluate immediate phase reactions.  相似文献   
125.
This paper puts forth an Internet-based architecture for machine-to-machine communication and computation that enhances bio-productivity in agriculture. The approach utilizes an auxiliary language to enable data interoperability in a synthetic computing environment and to make connections between data and mathematical models. The approach also includes some aspects of cloud and context aware computing. At the prototype level, a practical application from the Florida citrus industry demonstrates the concept. In general, future agricultural systems will be Internet-based thus reducing cost and increasing capability. Standards organizations are certain to play an important role in this development, which might continue for the next decade or longer.  相似文献   
126.
High levels of mortality in Pacific oysters Crassostrea gigas in the Republic of Ireland were recorded during the summer of 2009. The new variant of Ostreid herpes 1 (OsHV-1 μVar) which first emerged in France in 2008 was identified from affected stocks. Retrospective data was collected from 70 oyster farmers through an interviewer-administered questionnaire to investigate the distribution and determinants of the mortality. Based on farmer recall, data were recorded at the batch level for cumulative mortality during 2009, start dates and duration of the mortality event and the age of animals affected. Observable mortalities were recorded in 109 out of 346 batches at 47 sites; 104 of the 109 batches were located in bays where OsHV-1 μVar had been detected. The records from bays where OsHV-1 μVar had been detected were analysed to characterize the pattern of mortality and potential risk factors. Batch mortality averaged 37% (18-65% quartiles) but showed a bimodal distribution (half the batches had mortality less than 45%). Mortalities started at the end of May and continued until early August, peaking in early July. On average oysters died over a period of 18 days. Mortality varied considerably both between and within bays. Mortality started in recently introduced batches and occurred later in the summer in established oysters, which is consistent with the introduction of an infectious agent. Mortality was significantly lower in adults compared with other age groups, which supports observations from France. Three variables were significantly (P<0.05) associated, in both bivariate screening and a logistic regression, with high batch-level mortality (>40%): oysters (i) introduced as juveniles, (ii) during or since the winter of 2008/9 and (iii) which spent less than 8h out of water (in a tidal cycle) (compared with oysters introduced as adults before the winter of 2008/9 and spending more than 8h out of water). Twenty-one percent of triploid batches experienced "high" (>40%) mortality compared with 10% for diploid batches which was significant (P<0.05) in the initial bivariate screening but not in the final logistic regression model. Future studies should develop improved methods to assess oyster mortality and follow stocks over time to better determine the influence of management and environmental factors on mortality.  相似文献   
127.
The principal defense of tropical forests has been to designate them as protected areas, but few of these protected areas have been studied to determine their effectiveness at preventing forest clearance within their boundaries. We used remote sensing techniques to quantify three fundamental forest cover change processes: forest clearance, re-growth and fragmentation over a 19-year time period, in a National Park of Jamaica. Results show that forest clearance occurred at similar high levels prior and subsequent to the establishment of the area as a National Park in 1993: 1.50% yr−1 (1983–1992) and 1.42% yr−1 (1992–2002), respectively. Fragmentation continued post-establishment, and manifested itself in an increasing number of smaller more vulnerable fragments; the number of fragments increased by 60%, and the mean fragment size decreased by 40%. Core areas decreased with ensuing increases in edge lengths, and fragments became more isolated from one another. After designation as a National Park however, increased forest re-growth occurred, resulting in a 63% decline in the net deforestation rate from 0.80% yr−1 (1983–1992) to 0.26% yr−1 (1992–2002). Image classifications gave accuracies of 90–97% (Kappa 0.80–0.93). Although the decrease in net deforestation may indicate some level of success of this National Park, forest clearance and fragmentation, leading to species shifts and biodiversity loss were still present at pre-National Park levels. We then examined the preponderance of successful protected areas, and found that success may be an artifact of the most widely used method of assessment, which compares deforestation rates inside versus outside protected areas.  相似文献   
128.
Two media used for recovery of foodborne Staphylococcus aureus were compared: trypticase soy broth with 10% salt (TSBS), used in the official AOAC method, and TSBS with 1% sodium pyruvate added (PTSB). Adding pyruvate increased recovery of 4 heat-stressed and nonstressed S. aureus foodborne strains from artificially contaminated mashed potato and ham salad substrates. The overall geometric means for the 2 media differed significantly at the alpha = 0.05 level. Recovery of S. aureus from 70 replicates of naturally contaminated Monterey Jack cheese was highest in PTSB. The overall geometric means/g were 63 in TSBS and 96 in PTSB.  相似文献   
129.
A gas chromatographic method that identifies sporeformers as the cause of spoilage in swollen cans of low-acid foods was collaboratively studied in 2 stages. Two organic compounds produced by sporeformers, D-(-)-2,3-butanediol and butyric acid, are measured in the upper phase after centrifugation of the liquid portion of the can contents. Each sample is assayed on 2 packed columns designed for the assay of aqueous solutions of volatile fatty acids, using flame ionization detectors. For study 1, 16 duplicate inoculated cans of cream-style corn and beef noodle soup were sent to 9 collaborators. For study 2, 7 collaborators received 11 duplicate inoculated cans of the 2 foods. Duplicate uninoculated cans of each food served as negative controls. The inocula were 6 sporeforming organisms (4 Clostridium and 2 gas-forming Bacillus species) and 2 nonsporeformers. After the deletion of marginal samples, the percentages of correctly identified sporeformers and nonsporeformers in beef noodle soup were 83 (110/132) and 90 (54/60), respectively; corresponding percentages for cream-style corn were 80 (98/123) and 100 (35/35). The method has been adopted official first action.  相似文献   
130.
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