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941.
High-performance liquid chromatography-electrospray ionization mass spectrometry (HPLC-ESI-MS) and tandem mass spectrometry (MS(n)) were used to investigate the phenolic constituents in methanol, water, and methanol/water extracts of Eucalyptus globulus Labill. bark. Twenty-nine phenolic compounds were identified, 16 of them referenced for the first time as constituents of E. globulus bark, namely, quinic, dihydroxyphenylacetic, and caffeic acids, bis(hexahydroxydiphenoyl (HHDP))-glucose, galloyl-bis(HHDP)-glucose, galloyl-HHDP-glucose, isorhamentin-hexoside, quercetin-hexoside, methylellagic acid (EA)-pentose conjugate, myricetin-rhamnoside, isorhamnetin-rhamnoside, mearnsetin, phloridzin, mearnsetin-hexoside, luteolin, and a proanthocyanidin B-type dimer. Digalloylglucose was identified as the major compound in the methanol and methanol/water extracts, followed by isorhamnetin-rhamnoside in the methanol extract and by catechin in the methanol/water extract, whereas in the water extract catechin and galloyl- HHDP-glucose were identified as the predominant components. The methanol/water extract was shown be the most efficient to isolate phenolic compounds identified in E. globulus bark.  相似文献   
942.
The protection of exploited species offered by marine reserves is maximised if individual fish live within the boundaries of the reserve for most of their lives. The direct benefit of this protection, the so called ‘reserve effect’, is the build-up of biomass through an increase in individual numbers and size. This effect can take several years depending on the life history traits of the target species. However, empirical studies on individual fish spatial behaviour at temporal scales long enough to be compatible with that of invoking the reserve effect are still virtually lacking. We studied the inter-annual patterns of habitat use of the dusky grouper (Epinephelusmarginatus), an endangered reef fish predator, using passive acoustic telemetry inside and around a small marine reserve in the Azores, mid-north Atlantic. All 11 individuals resided in the reserve year-round for up to 5 years. During these periods, fish were detected nearly every day and utilised stable core activity areas. Two smaller fish apparently abandoned the area after some time, probably relocating outside the reserve. Our results indicate that even small marine reserves can promote the long-term recovery of some endangered species if the long-term behaviour (i.e. site fidelity) of individuals is appropriate. This result bears direct implications for most existing coastal marine reserves, given that they fall into the small size range and many overexploited reef fish species may be highly site attached.  相似文献   
943.
Detailed patterns and preferences of informal wood extraction were investigated in an urban forest used by slum inhabitants of Nairobi, Kenya, as such information determines the sustainability of resource use. Instead of asking the people what they had secretly cut, a survey was conducted of the stumps and trees left in the forest to (i) evaluate how accessibility and patrolling affected spatial patterns of resource use, and to (ii) estimate a broad spectrum of species and species-specific size preferences. Both probability and size of cutting increased with better accessibility (represented by distance from the slum), and stump size exceeded that of living stem size around 1.7 km from the slum, which suggested magnified impact of tree cutting near the slum. Patrolling (represented by distance from ranger stations) had little effect in reducing the probability of cutting but was effective in reducing cut size. With the use of random effect models, a broad species preference spectrum (including less abundant and non-preferred species) was estimated, which indicated trends in vegetation change. Smaller stems were preferred for most species presumably used for domestic fuelwood, but major exploitation of large Brachylaena huillensis stems traded in the woodcarving industry was also revealed. Such detailed information on informal wood use can help forest managers to understand threats to the forests as well as the needs of local communities. This is a first step to redefining ‘acceptable’ resource use by the local community for their increased role and responsibility in sustainable forest management, especially when conventional controls of informal activities (i.e. exclusion and penalty) are not functioning well.  相似文献   
944.
945.
946.
Saliva appears as a defence mechanism, against potential negative effects of tannins, in some species of animals which have to deal with these plant secondary metabolites in their regular diets. This study was carried out to investigate changes in parotid saliva protein profiles of sheep (Ovis aries) and goats (Capra hircus), induced by condensed tannin ingestion. Five Merino sheep and five Serpentina goats were maintained on a quebracho tannin enriched diet for 10 days. Saliva was collected through catheters inserted on parotid ducts and salivary proteins were separated by two-dimensional gel electrophoresis. Matrix-assisted Laser desorption ionization - time of flight (MALDI-TOF) and liquid chromatography tandem mass spectrometry (LC-MS/MS) were used to identify the proteins whose expression levels changed after tannin consumption. Although no new proteins appeared, quebracho tannin consumption increased saliva total protein concentration and produced changes in the proteome of both species. While some proteins were similarly altered in both species parotid salivary protein profile, sheep and goats also presented species-specific differences in response to tannin consumption.  相似文献   
947.
Teat number is an important trait in sows that should accompany the increase in litter size that has been achieved in the last decades through selection. We have previously identified a genome-wide significant QTL for teat number in porcine chromosome SSC5 by means of an experimental Meishan by Iberian F(2) intercross population. In the present report, we have studied the porcine parathyroid hormone-like hormone (PTHLH) gene, which maps to SSC5, as a candidate gene for this trait, as PTHLH is involved in nipple formation during embryogenesis and nipple development during pregnancy and lactation. We have found that porcine PTHLH gene is transcribed into three mRNA species differing in the 5'UTR region. Two of these variants are reported in pigs here for the first time: one was similar to variant 1 described in humans while the other, which was generated by the retention of two small introns, has not been identified before in any other species. In addition, mRNA expression profile for two of the mRNA variants was assessed in 19 pig tissues. Porcine PTHLH showed a widespread expression as it was present in all tested tissues and relative expression of each variant was tissue dependent. Finally, we have performed an association study between a non-synonymous mutation in the coding region of this gene and sow teat number. The PTHLH polymorphism was segregating in our Meishan by Iberian F(2) population at intermediate allelic frequencies. We compared here six different statistical models to choose the one with a better fit and a lower degree of complexity. However, despite the potential negative effect of the PTHLH mutation in the signal peptide of this protein, we did not detect any association between the PTHLH genotype and the sow teat number phenotype, concluding that the causal mutation of the observed QTL is very likely not related to this gene.  相似文献   
948.
The objective of this study was to determine the number, morphology and ultrastructure of preantral ovarian follicles of buffalo (Bubalus bubalis) foetuses at different ages. Quantification revealed number of primordial, primary and secondary follicles of 48 857 ± 17 506, 26 000 ± 20 452, 18 428 ± 10 875 and 18 375 ± 19 690, 225 ± 349, 326 ± 288 at 12–34 cm and 35–60 cm crown rump length (CRL), respectively. Follicular diameter values were 28.9 (±3.4), 34.7 (±5.9) and 59.4 (±12.6) μm; oocyte diameters were 21.7 (±2.8), 24.3 (±3.4) and 33.0 (±7.7) μm, and the numbers of follicular cells in the follicle equatorial section were 7.1 (±1.4), 12.0 (±2.4) and 13.8 (±2.4) for primordial, primary and secondary follicles, respectively. The primordial follicle consisted of an oocyte surrounded by a layer of flattened follicular cells with a normally eccentric oocyte nucleus. Dispersed Golgi complex, smooth endoplasmic reticulum, rounded mitochondria and several lipid vesicles were observed in the cytoplasm and cell junctions between the follicle cell membranes and the oocyte. This work describes the number, morphometry and ultrastructure of preantral follicles of buffalo foetuses, concluding that folliculogenesis is established between 8 and 34 cm CRL and that follicle number varies individually and according to age and that further studies are needed in this species.  相似文献   
949.
Patch burning is the deliberate application of fire to a management unit in a heterogeneous manner, resulting in the heterogeneous distribution of grazing animal impact. The application of patch burning typically has been discussed within a framework of imposing heterogeneity on a homogeneous landscape or management unit, yet most landscapes and management units are actually distinguished by an inherent level of heterogeneity. Within landscapes and management units, differing topography and soils interact to create patterns of contrasting patches, also known as topoedaphic sites. Thus, introduction of a heterogeneous disturbance such as patch burning on a landscape or management unit is more accurately described as the imposition of one layer of heterogeneity onto a pre-existing layer of heterogeneity. We examined effects of patch burning on vegetation structure and animal distribution across contrasting topographical sites in sand sagebrush (Artemisia filifolia Torr.) shrubland of the southern Great Plains in North America. Landscapes at our study site were characterized by an inherent amount of heterogeneity in vegetation structure due to variability in topoedaphic sites, and the patch burning treatment superimposed additional heterogeneity that was constrained by topoedaphic characteristics. Shrub-dominated sites were more dependent on patch burning for heterogeneity of vegetation structure than sites dominated by short grasses. Distribution patterns of cattle (Bos taurus) were not significantly different across treatments, though they followed patterns similar to previous studies. We demonstrated that heterogeneity was dependent on topoedaphic patterns and the application of patch burning management for heterogeneity was dependent on the inherent variability of a landscape.  相似文献   
950.
An outbreak of necrotic enteritis caused by Clostridium perfringens type C was diagnosed in captive collared (Pecari tajacu) and white-lipped (Tayassu pecari) peccaries housed in the Laboratory of Applied Ethology of Universidade Estadual de Santa Cruz located in Ilhéus, State of Bahia, Brazil. Four collared peccaries and three white-lipped peccaries, all juveniles (25-105 days old), were affected. For all affected animals, lethargy and inappetance were followed by sudden death within 24 hours. Histopathology of intestinal wall, culture of C. perfringens type C, and the identification of beta-toxin from intestinal content confirmed the diagnosis.  相似文献   
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