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11.
Journal of Pest Science - Conflicting views regarding synthetic pesticides include the successful use as pest management tools for agriculture and forestry on one hand and the threats to components...  相似文献   
12.
Journal of Pest Science - Longhorn beetles are commonly moved among continents within wood packaging materials used in trades. Visual inspections carried out at points of entry often fail to detect...  相似文献   
13.
A feeding experiment was carried out to determine the efficiency of different commercial sources, chemical forms and levels, of dietary astaxanthin, to appropriately pigment the red porgy (Pagrus pagrus) skin. According to this, total carotenoid content, profiles and chemical forms present in the skin were determined. In order to establish the potential for antioxidant protecting role of astaxanthin supplemented diets, peroxide levels and lipid composition of skin were also determined.

Red porgy alevins were fed six dietary treatments in triplicate; a basal diet (B) without carotenoids; two diets (N25 and N50) formulated to supply either 25 or 50 mg kg− 1 of an esterified source of astaxanthin (Haematococcus pluvialis, NatuRose™); two diets (CP25 and CP50) with either 25 or 50 mg kg− 1 of unesterified astaxanthin (Carophyll® Pink); and a positive control diet (B + S) proved as a successful pigmenting-diet in previous experiences (B + S, 88% basal diet:12% frozen shrimp) [Cejas, J., Almansa, E., Tejera, N., Jerez, S., Bolaños, A., Lorenzo, A., 2003. Effect of dietary supplementation with shrimp on skin pigmentation and lipid composition of red porgy (P. pagrus) alevins. Aquaculture 218, 457–469].

All fish fed carotenoid supplemented diets displayed a pink-coloured skin after 4 months of feeding in contrast to the greyish appearance displayed by fish fed the basal diet not supplemented with carotenoids (B). Furthermore, astaxanthin diesters were the major carotenoid in the skin of pink fish. A second carotenoid, tentatively identified as tunaxanthin diester, was also detected. The best results in terms of skin natural reddish hue, total carotenoid and astaxanthin contents were found by using the esterified forms of dietary astaxanthin (N25, N50 and B + S). Interestingly, the lowest levels of lipid peroxides were found in the fish fed these three treatments. However, no effect of treatment on lipid composition was found. In conclusion, red porgy alevins are able to efficiently utilise dietary natural or synthetic astaxanthin, and deposit this pigment in its esterified form to acquire an acceptable pink-coloured skin compared to that of the wild fish.  相似文献   

14.
Long pentraxin 3 (PTX3) is a conserved pattern-recognition secreted protein and a host-defence-related component of the humoral innate immune system. The aim of the present study was to characterize swine PTX3 (SwPTX3) protein expression in influenza virus infected pigs. First, we performed in silico studies to evaluate the cross-reactivity of PTX3 human antibodies against SwPTX3. Secondly, we used in vitro analysis to detect SwPTX3 presence in swine bone marrow dendritic cells (SwBMDC) upon stimulation with different agents by Western blot and immunofluorescence. Finally, the levels of SwPTX3 were assessed in experimental infection of pigs with different strains of influenza virus. This is a novel study where the expression of SwPTX3 was evaluated in the context of a pathogen infection. The initial characterization of SwPTX3 in influenza virus infected pigs contributes to understand the role of PTX proteins in the immune response.  相似文献   
15.
This review of the use of thermographic technique in equines introduces the principles upon which infrared radiation and thermoregulatory physiology are based and describes the instrumentation used and its practical use. The advantage of this imaging technique is that it is a noninvasive thermographic examination, both from an operational (the animal and the operator) and health (no penetrating radiation is used) standpoint. Advantages and disadvantages of this technique, equine applications, and physiological assessments are discussed.  相似文献   
16.
Loss of semi-natural grasslands and reduction of habitat diversity are considered major potential threats to arthropod diversity in agricultural landscapes. The main aim of this study was to investigate how area and habitat diversity, mediated by shrub encroachment after grassland abandonment, affect species richness of orthopterans in island-like grasslands, and how contrasting mobility might alter species richness response to both factors. We selected 35 isolated patches in landscapes dominated by arable land (durum wheat) in order to obtain two statistically uncorrelated gradients: (i) one in habitat area ranging from 0.2 to 55 ha and (ii) one in habitat diversity ranging from patches dominated by one habitat (either open grasslands or shrublands) to patches with a mosaic of different habitats. Habitat loss due to land-use conversion into arable fields was associated with a substantial loss of species with a positive species-area relationship (SAR), with sedentary species having a steeper and stronger SAR than mobile species. Halting habitat loss is, therefore, needed to avoid further species extinctions. Shrub encroachment, triggered by abandonment, presented a hump-shaped relationship with habitat diversity. An increase in habitat diversity enhanced species richness irrespective of patch area and mobility. Maintaining or enhancing habitat diversity, by cutting or burning small sectors and by reintroducing extensive sheep grazing into abandoned grassland, are suggested as complementary strategies to mitigate further decline of orthopteran diversity in the remnant patches. This would be equally important in both small and large patches.  相似文献   
17.
In order to find out a new effective accumulator of polycyclic aromatic hydrocarbons (PAHs) useful for monitoring studies on a large scale and low costs, the accumulation capacity of both biological and artificial matrixes (mosses and polyester fibers, respectively) has been tested. For this purposes, Hypnum cupressiforme and dacron® were exposed to pollution airborne in two sites located nearby an active iron industry and in center of the town of Trieste, where high PAH pollution spots, due to vehicular traffic, are usually detected. The samplers were exposed in six sampling sessions for 21 days. The results obtained were compared with data collected by active PAH samplers, usually employed for official widespread monitoring. The level of correlation between the data sets was calculated. Furthermore, a repeatability study of data was performed. According to the results, both matrixes are good PAH accumulators, though they show different skills.  相似文献   
18.
Infection by Cryptosporidium parvum has been detected for the first time in cattle and swine in Galicia (N.W. Spain). The organisms were also found in one of 69 sheep examined. Although in most cases the parasite was found in young diarrhoeic animals, its presence in asymptomatic mature cattle and piglets was also detected.  相似文献   
19.
This paper focuses on the analysis of the slope and catchment erosion dynamics in a typical Mediterranean context and its sensitivity to recent climatic and socio‐economic changes. The main objective of the present study is to test the reliability of digital photogrammetric analysis to evaluate the time and space evolution of erosion processes mainly triggered by surface running waters and landslides for about the last 60 years. The selected test area is the Landola catchment, a minor tributary of the Upper Orcia River Valley (Southern Tuscany). The Upper Orcia valley is a key site for the comprehension of denudation processes typically acting in Mediterranean badland areas thanks to the following: (i) the availability of long‐lasting erosion monitoring datasets (20 years' long direct measurements at erosion ‘hot spots’); (ii) its representativeness as a sub‐humid Mediterranean badland area; and (iii) the rapidity of development of erosion processes, which makes it suitable as an open‐air laboratory for the study of badland dynamics. The outputs of this work highlight that the application of high‐resolution digital photogrammetric methodologies can represent a powerful and low‐cost tool to evaluate rates and spatial–temporal distribution of denudation processes, as confirmed by the validation through field point monitoring in areas close to the study area. The results obtained for the study area confirm that high erosion rates are a persistent environmental problem for the Upper Orcia Valley, which is not solved up to now, despite various land conservation interventions. The performed multi‐temporal analysis shows a slight decrease in the average water erosion rate during the last 60 years and a parallel increase in the frequency of mass wasting events. These variations are most likely related to a complex interplay between land use changes that have affected the study area during the studied period, revealing a very delicate equilibrium between farming activities and erosion processes. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
20.
Banana and plantain are among the most important food crops in developing countries but production is threatened by increasing virulent forms of Fusarium oxysporum f. sp. cubense. Chemical control is not economically effective and,therefore, breeding programs are necessary. Traditional field studies of new genotype resistance to this disease are time-consuming and destructive. Therefore,we developed a rapid and non-destructive procedure to differentiate field-grown banana resistant from susceptible clones. This procedure implicates application of culture filtrates of Fusarium oxysporum f. sp. cubense race 1 onto banana leaves. The relationship between duration of the fungal in vitro incubation, and the fungal culture fresh mass, the culture filtrate absorbency, and the Gross Michel (susceptible cultivar)leaf lesion area (after application of the culture filtrate) were similar and at 24day-incubation the highest values of the recorded indicators were observed. A comparison between Gross Michel and FHIA-01(resistant) was also performed. The most relevant differences between cultivars were observed at 48 hours after application of the culture filtrate, and in the middle-aged leaves. The position of the culture filtrate application in the leaf limb (distal, middle, proximal) was not determinant. A wider comparison among banana cultivars confirmed previous results informed by other researchers using different systems to study this plant-fungus interaction. Such a confirmation validates the effectiveness of the procedure described here to select rapid and non-destructively banana resistance to this disease at field level. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
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