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191.
Populations of migratory birds can be affected by events happening at both breeding and wintering grounds. The Sahel is a vast region holding a large number of wintering trans-Saharan migratory European birds, and current land-use changes there may represent a threat for these species. We used satellite tracking data from the migratory Montagu’s harrier to evaluate habitat use of the species during the wintering season, and whether the current network of protected areas is effective to provide their habitat needs during that season. We also developed an ecological niche model for the species in Western-Central Sahel to check if the most suitable sites are included within current protected areas. Tracked harriers occupied a large region encompassing a total of eight countries. The most preferred habitats during winter were croplands and some natural vegetation habitats, especially grasslands. Protected areas only covered a small proportion of the overall wintering grounds of tracked harriers and the most suitable areas for the species in Western-Central Sahel. Increasing the extent of preferred natural habitats within protected areas should benefit the conservation of this and probably other insect-eating raptors. However, substantial increases in extent and number of protected areas in sub-Saharan Africa are very unlike to occur. Conservation actions in the region should therefore be mostly focused on improving land use planning and management outside protected areas, specially enhancing agricultural practices to make biodiversity conservation compatible with poverty alleviation. These can be chiefly targeted at an area of <20,000 km2 of very suitable habitat for these species.  相似文献   
192.
The Capsicum genus is native to tropical America and consists of 27 species, five of which are used as fresh vegetables and spices: Capsicum annuum L., Capsicum chinense Jacq., Capsicum frutescens L., Capsicum baccatum L. and Capsicum pubescens R. et P. The study of the relationships among species of cultivate Capsicum species will be useful for breeding new cultivars or hybrids. This study is focused on the genetic diversity and relationships of these species that were collected in the Andean region. Ten microsatellites and four AFLP combinations were used to characterize 260 Capsicum accessions. The AFLP tree turned out to be informative regarding relationships among species. The data clearly showed the close relationships between C. chinense and C. frutescens. Moreover, C. cardenasii and C. eximium were indistinguishable as a single, morphologically variable species. Our data showed C. baccatum and C. praetermissum to be distinct species that form a compact group. In the present work, AFLP fingerprinting indicated that C. chacoense was placed in the C. baccatum complex and showed C. tovarii as a separate species. In addition, SSR data indicated that there is intraspecific differentiation in the species C. chinense, C. baccatum and C. pubescens, as the PCoA-based clustering showed a clear geographic division related to country. Even though Bolivia is considered to be the nuclear area for these species, we have found similar variability in Ecuador and Peru for several Capsicum species.  相似文献   
193.
BACKGROUND: The control of Ceratitis capitata Wiedemann traditionally has relied on chemical control with organophosphate insecticides. The use of many of these substances has been banned by new European directives; therefore, the development of new control methods is essential to manage this pest. Bait sprays with spinosad, mass trapping and lure‐and‐kill techniques have been the base for new integrated pest management programmes. In this study, a 2 year field trial was conducted in two citrus areas to test the efficacy of attract‐and‐kill devices against mass trapping and spinosad‐plus‐bait treatments. RESULTS: The Magnet® MED attract‐and‐kill device, Spintor® treatments and mass trapping achieved good control of C. capitata populations, as confirmed by low percentages of damaged fruit in the assessments performed during the harvest period. On the other hand, fly population levels on plots treated with other attract‐and‐kill prototype devices increased more than threefold by comparison with the populations recorded in the rest of the treated plots. The same effect was observed for fruit damage, with 6–8 times less damage with Magnet® MED and spinosad treatments, respectively, than with the attract‐and‐kill prototype devices. CONCLUSION: By using an effective attractant, conventional trapping systems can be replaced with cheaper and easier‐to‐handle attract‐and‐kill devices. The efficacy of these devices and their advantages over conventional mass trapping systems are discussed. © 2012 Society of Chemical Industry  相似文献   
194.
The objectives of this study were to evaluate the effects of season in southeast of Brazil comparing genotypes on semen characteristics, freezability and peripheral plasma concentrations of testosterone. Ejaculates of five Bos indicus bulls and six Bos taurus bulls were evaluated over a period of 27 months, which was divided into winter (July, August, September), spring (October, November, December), summer (January, February, March) and autumn (April, May, June). Semen was evaluated according to standard procedures for ejaculate volume, sperm concentration, gross-motility, progressive motility and sperm morphology. After preparing and freezing the ejaculates according to commercial procedures, the straws were stored in liquid N2 until post-thaw evaluation. Ejaculate volume, sperm concentration, gross-motility, progressive sperm motility, vigor and morphological sperm defects were significantly influenced by season and genotype (p < 0.05). Heat tolerance was better in B. indicus bulls than in B. taurus bulls characterized by lower values of sperm abnormalities throughout the observation period. The highest values were recorded for abnormal heads followed by cytoplasmatic droplets in B. taurus bulls. The proportion of ejaculates which were eliminated before freezing for reasons of bad quality was lower in the B. indicus bulls. Temporal changes in peripheral plasma testosterone concentrations were higher in B. indicus bulls than in B. taurus bulls not revealing seasonal influences. The results of this study show clear genotype differences regarding semen quality. Freezability of B. taurus semen varies considerably throughout the year, leading to a high proportion of eliminated ejaculates. Collecting semen from B. taurus bulls during the summer in an artificial insemination centre may not be profitable.  相似文献   
195.
We describe the distribution of tuberculosis-like lesions (TBL) in wild boar (Sus scrofa) and red deer (Cervus elaphus) in Spain. Animals with TBL were confirmed in 84.21% of mixed populations (n=57) of red deer and wild boar and in 75% of populations of wild boar alone (n=8) in central and southern Spain (core area). The prevalence of TBL declined towards the periphery of this region. In the core area, the prevalence ranged up to 100% in local populations of wild boar (mean estate prevalence 42.51%) and up to 50% in red deer (mean estate prevalence 13.70%). We carried out exploratory statistical analyses to describe the epidemiology of TBL in both species throughout the core area. Prevalence of TBL increased with age in both species. Wild boar and red deer mean TBL prevalence at the estate level were positively associated, and lesion scores were consistently higher in wild boars than in red deer. The wild boar prevalence of TBL in wild boar did not differ between populations that were or were not cohabiting with red deer. Amongst the wild boars with TBL, 61.19% presented generalized lesions, and the proportion of generalized cases was similar between sex and age classes. In red deer, 57.14% of TBL-positive individuals presented generalized lesions, and the percentage of generalized cases increased with age class, but did not differ between the sexes. These results highlight the potential importance of wild boar and red deer in the maintenance of tuberculosis in south central Spain.  相似文献   
196.
AIM: To establish the optimal dose of the mitogen phytohaemagglutinin (PHA) and the optimal time for measuring increased skin-fold thickness in red deer following intradermal injection, as an indicator of cell-mediated immune response. METHODS: Three doses (10, 50 and 250 microg) of PHA were injected intradermally in the right side of the neck, and phosphate buffered saline (PBS) was injected at a fourth site as a control, in 20 captive Iberian red deer (Cervus elaphus hispanicus) hinds. Skin-fold thicknesses were measured at 0, 12, 24, 36, 48, 60, 72, 84 and 96 h following injection. RESULTS: The highest dose of PHA tested (250 microg) resulted in a clear and long-lasting cellular response; increases in skin-fold thickness between 48 and 84 h post-injection varied minimally and response correlated positively with liveweight. No correlations with liveweight and no clear increases in skin-fold thickness occurred at the lower doses of PHA or the PBS. CONCLUSIONS AND CLINICAL RELEVANCE: This technique could be applied with minimal training and without specialised equipment in deer, for immunological and ecological research.  相似文献   
197.
A model based on physicochemical parameters has been developed and applied to the study of the kinetics of extraction of aroma compounds from oak casks having been used a variable number of times. Two major deviations from the model can be observed: a strong seasonal dependence of extraction (unexpected in a thermostated cellar); and higher yields with a smaller number of longer extractions. 4-Propylguaiacol follows both behaviors, and its levels have been found to be closely related to those of 4-ethylguaiacol and to the number of uses of the barrel, which suggests that this compound may be formed by the same microorganisms forming ethylphenols from a precursor found in wood. Although the extraction kinetics of all aroma compounds appear to be more or less mediated by the action of microorganisms, those of whiskeylactones, eugenol, and 4-allyl-2,6-dimethoxyphenol are more in accordance with the physicochemical model, whereas those of vanillin, syringaldehyde, furfuryl alcohol, and, of course, 4-propylguaiacol are much more coherent with a microbiological extraction/formation.  相似文献   
198.
The volatile fractions of three tomato cultivars (p73, Jorge, and Durinta) were studied in both free and glycosidically bound forms. The possibility of increasing the concentration of free volatile compounds by adding selected glycosidases was also tested. The free volatile fraction (FVF) of tomato juice was directly determined by headspace solid-phase microextraction (SPME). To analyze the glycosidically bound fraction (GBF), tomato juice samples were extracted with C18 cartridges and the resulting glycoside extracts were enzymatically hydrolyzed. The released aglycons were determined by headspace SPME. Of these compounds, six were not previously reported to belong to the tomato GBF. The concentration of 21 of 24 compounds detected in the FVF was significantly different between cultivars, the majority of them being greater in p73 than in Durinta and Jorge cultivars. In the GBF, 19 of 26 compounds that were detected were significantly different between cultivars but only the amount of trans-linalool oxide was significantly the greatest in the p73 cultivar. The addition of Candida molischiana beta-glucosidase (BGLN) and Saccharomyces cerevisiae exoglucanase (EXG1) to tomato juice samples led to increases in the concentration of 10 compounds, with variations depending on the cultivar or enzyme. These results provide scientific support for using glycosidases as a tool to improve tomato aroma.  相似文献   
199.
This prospective study used radiographic techniques to evaluate the inclination, Norberg, quadriceps and femoral varus angles, and the patellar position in dogs with developmental medial patellar luxation. The study also compared these measurements pre- and post-operatively to determine how they were affected by surgical procedures. Eighteen dogs with unilateral or bilateral luxation were used, and 4 groups were established according to luxation grade. Except for the quadriceps angle, there was no difference among the groups preoperatively. Significant differences for the quadriceps angle were observed between Grades 1 and 3, and between Grades 2 and 3. The Norberg and femoral varus angles and the patellar position showed no changes between pre- and postoperative groups. However, measurements of the preoperative quadriceps angle and postoperative inclination angle may be useful for evaluating dogs with grade-3 luxation. Further studies using other imaging techniques are required in dogs with severe grade-4 luxation due to the difficulty in obtaining a good radiographic position.  相似文献   
200.
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