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1.
Marine protected areas (MPAs) are often promoted as tools for biodiversity conservation as well as for fisheries management. Despite increasing evidence of their usefulness, questions remain regarding the optimal design of MPAs, in particular concerning their function as fisheries management tools, for which empirical studies are still lacking. Using 28 data sets from seven MPAs in Southern Europe, we developed a meta‐analytical approach to investigate the effects of protection on adjacent fisheries and asking how these effects are influenced by MPA size and age. Southern European MPAs showed clear effects on the surrounding fisheries, on the ‘catch per unit effort’ (CPUE) of target species, but especially on the CPUE of the marketable catch. These effects depended on the time of protection and on the size of the no‐take area. CPUE of both target species and the marketable catch increased gradually by 2–4% per year over a long time period (at least 30 years). The influence of the size of the no‐take area appeared to be more complex. The catch rates of the entire fishery in and around the MPA were higher when the no‐take areas were smaller. Conversely, catch rates of selected fisheries that were expected to benefit most from protection increased when the no‐take area was larger. Our results emphasize the importance of MPA size on its export functions and suggest that an adequate, often extended, time frame be used for the management and the evaluation of effectiveness of MPAs.  相似文献   
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In 1998, two cases of silica urolithiasis occurred in castrated male dromedaries on an intensive camel farm in the Canary Islands. The immediate attributable cause was the ingestion of large amounts of silica in the feed, estimated as 84.44 g/day. An associated cause was the low level of salt in the diet. Daily ingestion of salt from feed and water was estimated to be 21.8 g (8.6 g of sodium). Seventy-six castrated males from the same farm were divided into four groups: group A received 30 g of salt daily; group B received 40 g; group C received 60 g; and group D received no added salt in the diet (control). The animals were maintained on these dietary regimes for 2 years. No animals from groups A, B or C suffered overt urinary retention. One animal from group D had an obstructive urinary retention 10 months after the study commenced. Thus, 52 g of salt daily appears to be sufficient to prevent urinary retention in dromedaries raised in a subtropical climate.  相似文献   
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The phenolic content of lavandin waste obtained after the distillation of essential oils for the perfume industry was investigated to find an alternative use for this material. The antioxidant activity of different fractions as well as their total phenolic content were evaluated by different methods. Twenty-three phenolic compounds were identified by liquid chromatography coupled to ionspray mass spectrometry (LC/MS/MS), including phenolic acids, hydroxycinnamoylquinic acid derivatives, glucosides of hydroxycinnamic acids, and flavonoids, none of which have previously been reported in lavandin waste. Some structure-activity relationships were proposed by relating the type of scavenging activity of different fractions with the identified phenolic compounds. Contents of representative phenolic acids of Lamiaceae (chlorogenic and rosmarinic) were evaluated by high performance liquid chromatography-diode array detection (HPLC-DAD) and compared with those of other plant species.  相似文献   
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The aim of the present study was to evaluate the effect of trace mineral nutrition on sow performance, mineral content, and intestinal gene expression of neonate piglets when inorganic mineral sources (ITM) were partially replaced by their organic mineral (OTM) counterparts. At 35 d postmating, under commercial conditions, a total of 240 hyperprolific multiparous sows were allocated into three experimental diets: 1) ITM: with Zn, Cu, and Mn at 80, 15, and 60 mg/kg, respectively; 2) partial replacement trace mineral source (Replace): with a 30 % replacement of ITM by OTM, resulting in ITM + OTM supplementation of Zn (56 + 24 mg/kg), Cu (10.5 + 4.5 mg/kg), and Mn (42 + 18 mg/kg); and 3) Reduce and replace mineral source (R&R): reducing a 50% of the ITM source of Zn (40 + 24 mg/kg), Cu (7.5 + 4.5 mg/kg), and Mn (30 + 18 mg/kg). At farrowing, 40 piglets were selected, based on birth weight (light: <800 g, and average: >1,200 g), for sampling. Since the present study aimed to reflect results under commercial conditions, it was difficult to get an equal parity number between the experimental diets. Overall, no differences between experimental diets on sow reproductive performance were observed. Light piglets had a lower mineral content (P < 0.05) and a downregulation of several genes (P < 0.10) involved in physiological functions compared with their average littermates. Neonate piglets born from Replace sows had an upregulation of genes involved in functions like immunity and gut barrier, compared with those born from ITM sows (P < 0.10), particularly in light piglets. In conclusion, the partial replacement of ITM by their OTM counterparts represents an alternative to the totally inorganic supplementation with improvements on neonate piglet gene expression, particularly in the smallest piglets of the litter. The lower trace mineral storage together with the greater downregulation of gut health genes exposed the immaturity and vulnerability of small piglets.  相似文献   
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ABSTRACT:   The demersal multispecies trawl fishery in the western Mediterranean Sea has a poor selectivity; large numbers of juvenile fish are caught when using the legislated 40-mm diamond mesh cod end. The selectivity of a flexible sorting grid with 20-mm bar spacing (BS20) installed in front the conventional trawl cod end was investigated. The standard covered cod end method was used. Data was adequate for analyzing the selectivity of European hake Merluccius merluccius , poor cod Trisopterus minutus , greater forkbeard Phycis blennoides and Norway lobster Nephrops norvegicus . The selectivity of the 20-mm sorting grid was compared with the performance of 40-mm diamond (DM40) and square mesh (SM40) cod ends. The effect of a guiding funnel on the performance of the grid (BS20-f) was also explored. Finally, the potential changes in yield per recruit (Y/R) and biomass per recruit (B/R) after implementing a sorting grid were explored. An overall improvement in the 50% selection length ( L 50 ) with all four species was substantial when comparing the BS20 to the DM40. Higher improvement in L 50 s was achieved when the grid was equipped with the guiding funnel. When comparing the performance of the BS20-f to the SM40, there was no marked difference in L 50 s. The Y/R and B/R, however, are substantially higher with BS20-f for poor cod and about the same for European hake. BS20 compared to SM40 achieved lower Y/R and B/R for all four species; the smallest difference was observed for Norway lobster. Further development is required if the sorting grid is to be introduced into commercial fisheries.  相似文献   
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A factorial design was used to study the effect of dietary oxidized sunflower oils (fresh, heated at low temperatures, and heated at high temperatures), DL-alpha-tocopheryl acetate (0 or 100 mg/kg), and Zn supplementation (0 or 600 mg/kg) on the composition, oxidative stability, and sensory quality of dark chicken meat with skin from animals fed with a Se supplement (Se-enriched yeast, 0.6 mg of Se/kg). The positional and geometrical isomers of linoleic acid were increased in raw meat from chickens fed oils oxidized at high temperatures. In addition, supplementation with alpha-tocopheryl acetate increased the alpha-tocopherol content, whereas 2-thiobarbituric acid (TBA) values and lipid hydroperoxide content were reduced. Likewise, TBA values, rancid aroma, and rancid flavor also decreased in cooked dark meat. However, none of the dietary factors studied affected consumer acceptability scores of cooked meat. Furthermore, Zn supplementation increased the Se content in raw meat.  相似文献   
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Mannose-specific lectins (MSLs) were isolated from the bulbs of 27 species of wild Spanish Narcissi and compared to the commercially available MSL from daffodil (Narcissus pseudonarcissus, NPA). Molecular weight analysis showed the monomers of all the MSLs were at, or around, 12.5 kD. Haemagglutination assays showed that the MSLs exhibited activities at up to four times greater than that displayed by NPA and other MSLs derived from other species such as Galanthus nivalus (snowdrop) and Allium ursinum (ramson). Elution profiles from ion exchange chromatography exhibited similarities for species within the same taxonomic section suggesting that this method could aid in species classification. Further analysis by isoelectric focusing showed many isolectins are present in vivo and that even within a single peak from ion exchange chromatography there are numerous isolectins present. The basis of the isolectin heterogeneity is suggested to reside in the tetraploidy (sometime triploidy) nature of Narcissus genes.  相似文献   
9.
The Eurasian badger (Meles meles) is included in Appendix III of the Bern Convention and protected by national laws in many European countries. Badger hair is used to manufacture luxury shaving brushes, although it is frequently argued that the hog badger (Arctonyx collaris), which in Europe is an introduced and unprotected species, is the origin of the hair used. We applied an extraction protocol to recover DNA from the unrooted hair of shaving brushes obtained from commercial companies in The Netherlands and Spain. The tested brushes originated from The Netherlands, Spain, France, Italy and the United Kingdom where the Eurasian badger is a protected species. We sequenced 191 bp of the mitochondrial DNA control region and 170 bp of the cytochrome b gene and compared the sequences obtained with Eurasian badger and hog badger reference sequences of the same mitochondrial DNA regions obtained in our laboratory and from GenBank. Sequences obtained from four shaving brushes were clearly hog badger sequences, whereas four sequences clustered with Eurasian badger sequences of both European and Asian origins. One of the shaving brushes made of Eurasian badger was produced in France, where it is legal to capture or trade the species under certain conditions. The remaining three brushes originated from The Netherlands, where it is illegal to possess, sell, transport or use for commercial purposes dead Eurasian badgers or products derived from them.  相似文献   
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