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991.
992.
Paul E. Kendra Amy L. Roda Wayne S. Montgomery Elena Q. Schnell Jerome Niogret Nancy D. Epsky Robert R. Heath 《Postharvest Biology and Technology》2011,59(2):143-149
Tephritid fruit flies are serious economic pests worldwide. As larvae, they feed and develop within the pulp of host fruits, making infestation difficult to detect by visual inspection. At U.S. ports of entry, incoming produce shipments are checked for infestation by manually cutting open a small sample of fruit and searching for tephritid larvae. Consequently, there is a need for more sensitive, high-throughput screening methods. This study evaluated gas chromatography (GC) as a potential technology for improved detection of hidden infestation. Grapefruits (Citrus × paradisi Macfad.) infested with immature stages of the Caribbean fruit fly Anastrepha suspensa (Loew) (Diptera: Tephritidae) were examined to determine if infested fruit emitted a chemical profile distinct from that of non-infested fruit. Peaks identified by GC analysis were grouped into three classes. Chemicals detected in similar quantities in all samples, or slightly elevated in infested samples, were regarded as non-diagnostic background volatiles. Chemicals highly elevated after oviposition, during the last instar exit stage, and in experimentally-pierced fruit were interpreted to be indicators of citrus peel injury, and included d-limonene and β-ocimene. Chemicals elevated exclusively in the larval infestation stages were considered indicators of feeding damage and potentially diagnostic of infestation, and included hexyl butanoate and an unidentified compound. The peaks associated with injury and feeding were also detectable with a portable ultra-fast GC analyzer that required less than 80 s per sample. Further studies will investigate the potential application of these results for development of a rapid, non-destructive screening method for detection of tephritid infestation. 相似文献
993.
Frederic Vandeperre Ruth M. Higgins Julio Sánchez‐Meca Francesc Maynou Raquel Goñi Pablo Martín‐Sosa Angel Pérez‐Ruzafa Pedro Afonso Iacopo Bertocci Romain Crec’hriou Giovanni D’Anna Mark Dimech Carmelo Dorta Oscar Esparza Jesús M. Falcón Aitor Forcada Ivan Guala Laurence Le Direach Concepción Marcos Celia Ojeda‐Martínez Carlo Pipitone Patrick J. Schembri Vanessa Stelzenmüller Ben Stobart Ricardo S. Santos 《Fish and Fisheries》2011,12(4):412-426
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
994.
Many fish species can withstand long period of food deprivation and consequently compensate for any weight loss by undergoing rapid growth during resumption of feeding. There is an interest in taking advantage of compensatory growth to reduce feed cost. In this present study, we attempted to compare the changes in hepatic mitochondrial proteome of zebrafish undergoing starvation and refeeding. Two‐dimensional gel separation and image analysis revealed a total of 65 spots that showed changes in expression after 15 days of starvation followed by 7 days of refeeding. A total of 35 proteins were selected for mass spectrometry analysis, resulting in the positive identification of 18 proteins. Identified proteins indicated that starvation resulted in reduction in glycolysis and increase in gluconeogenesis, while refeeding caused these activities to return to normal levels. Expression pattern of several proteins related to fatty acid and amino acid metabolism also suggested the utilization of non‐carbohydrate resources for energy during starving conditions. Proteins with chaperoning and antioxidative roles such as glucose‐regulated protein, paraxonase and heat‐shock protein were also upregulated in starved conditions. 相似文献
995.
996.
997.
Z. L. Zheng K. Y. Wang Delbert M. Gatlin III J. M. Ye 《Journal of the World Aquaculture Society》2011,42(4):549-557
This study was conducted to evaluate the potential of graded levels of GroBiotic®‐A to improve performance of Nile tilapia, Oreochromis niloticus, fed a 29% crude protein (CP) diet. A 29% CP diet was formulated and supplemented with 0, 0.4, 0.8, and 1.2% GroBiotic®‐A and compared to performance of fish fed a 33% CP diet. Enhanced weight gain and feed efficiency were generally observed in fish fed the diets supplemented with GroBiotic®‐A compared to the 29% CP diet. No significant differences in these responses were observed between fish fed diets supplemented with GroBiotic®‐A compared to those fed the 33% CP diet. Supplementation of 0.8 and 1.2% GroBiotic®‐A induced significantly lower condition factor and hepatosomatic index compared to fish fed the 29% CP diet, but those values were similar to that of fish fed the 33% CP diet. GroBiotic®‐A supplementation and protein reduction had no effect on the viscerosomatic index of fish or moisture, lipid, and protein content of muscle samples. However, muscle ash increased significantly with protein reduction (29% CP diet), but GroBiotic®‐A supplementation (0.8 and 1.2%) reduced muscle ash content. Activities of catalase and superoxide dismutase were markedly reduced in fish fed GroBiotic®‐A (0.8 and 1.2%) compared to those fed the control diet. GroBiotic®‐A supplementation also induced significantly higher neutrophil oxidative radical production compared to fish fed the 29% CP diet, but no significant difference was observed in comparison with the 33% CP diet. After 8 wk of feeding, exposure to Aeromonas hydrophila for 3 wk resulted in 40% (0.4, 0.8% GroBiotic®‐A) and 27% (1.2% GroBiotic®‐A) mortality and reduced signs of disease, while 47% mortality was observed in fish fed the 29% CP diet. Based on the result of this study, it is concluded that 0.8 and 1.2% GroBiotic®‐A positively influenced growth performance and feed efficiency of tilapia fed diets containing 29% crude protein to levels comparable to fish fed the 33% CP diet. GroBiotic®‐A supplementation also significantly increased neutrophil oxidative radical production as well as resistance to Ae. hydrophila infection. 相似文献
998.
M. ŘÍHA J. KUBEČKA M. PRCHALOVÁ T. MRKVIČKA M. ČECH V. DRAŠTÍK J. FROUZOVÁ E. HOHAUSOVÁ T. JŮZA M. KRATOCHVÍL J. PETERKA M. TUŠER M. VAŠEK 《Fisheries Management and Ecology》2011,18(4):339-347
Abstract Diel changes in littoral fish assemblage were studied in four reservoirs in the Czech Republic (Central Europe). The sampling was performed by beach seining in an unstructured littoral zone. Perch, Perca fluviatilis L., roach, Rutilus rutilus (L.), bream, Abramis brama (L.), carp, Cyprinus carpio L., ruffe, Gymnocephalus cernua (L.), pikeperch, Sander lucioperca (L.), eel, Anguilla anguilla (L.) and A. brama × R. rutilus hybrids exhibited higher densities at night. Only bleak, Alburnus alburnus (L.) exhibited higher densities during the day. The number of species was higher in night hauls, and mean body size of roach and bleak was also higher at night. Diel changes in fish densities resulted in the change in species composition between day and night. The study has implication for the sampling design to assess littoral fish assemblages using beach seine netting and recommends night sampling for a representative assessment or sampling during both diel periods for a robust assessment. 相似文献
999.
S. J. NEWMAN M. B. PEMBER B. M. ROME G. E. A. MITSOPOULOS C. L. SKEPPER Q. ALLSOP T. SAUNDERS A. C. BALLAGH L. VAN HERWERDEN R. N. GARRETT N. A. GRIBBLE J. M. STAPLEY J. J. MEEUWIG B. R. MOORE D. J. WELCH 《Fisheries Management and Ecology》2011,18(3):246-257
Abstract Stable isotopes of δ18O and δ13C in sagittal otolith carbonates were used to determine the stock structure of the polynemid Eleutheronema tetradactylum (Shaw) across tropical northern Australia, where this species is an important component of inshore commercial and recreational fisheries. Stable isotopes from the sagittal otolith carbonate of 470 fish from 11 discrete locations across western, northern and eastern Australia were sampled between 2007 and 2009. Analysis of these stable isotopes revealed different location‐specific signatures, indicating strong population subdivision. The significant differences in the isotopic signatures of E. tetradactylum demonstrated that there is unlikely to be substantial movement of fish between these locations. The spatial separation of these populations indicates a complex fine spatial scale stock structure across northern Australia, with at least 11 stocks or management units present. The population subdivision of E. tetradactylum was evident along expansive stretches of open beach systems and within coastal embayments with no physical barriers such as headlands. These results indicate that optimal fisheries management will require a review of the current spatial arrangements, particularly the potential for localised depletion of stocks on small spatial scales. 相似文献
1000.
Maurício Emerenciano Eduardo L. C. Ballester Ronaldo O. Cavalli Wilson Wasielesky 《Aquaculture International》2011,19(5):891-901
Biofloc rearing media provides a potential food source for shrimp reared in limited or zero water exchange systems. This culture
system is environmentally friendly as it is based on limited water use and minimal effluent is released into the surrounding
environment. In this study, we evaluated the survival, growth performance and salinity stress tolerance of pink shrimp Farfantepenaeus paulensis postlarvae reared from PL10 to PL25 in a biofloc technology limited water exchange system. PL (mean ± SD weight and length of 14 ± 10 mg and 8.10 ± 0.7 mm, respectively)
were reared in nine 40-L plastic tanks with a stocking density of 10PL/L. Three culture treatments were applied (1) culture
in the presence of bioflocs and commercial feed supply (FLOC + CF); (2) culture in the presence of biofloc without feed supply
(FLOC) and (3) culture in clear water with feed supply (control). Final biomass and survival were significantly higher in
FLOC + CF treatment than the control (P < 0.05), but did not differ from FLOC. PL reared in the FLOC + CF treatment achieved a significantly higher final weight,
weight gain and length in comparison with the other two treatments (P < 0.05). No significant difference (P > 0.05) between treatments was found for salinity tolerance over 24 and 48 h durations. The proximate analysis of floc shown
high levels of crude protein (30.4%), but low levels of crude lipids (0.5%). The continuous availability of bioflocs had a
significant effect on growth and survival of F. paulensis postlarvae cultured in BFT nursery systems. 相似文献