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141.
Assessing the Health of Grass Shrimp (Palaeomonetes pugio) Exposed to Natural and Anthropogenic Stressors: A Molecular Biomarker System 总被引:2,自引:0,他引:2
We developed a molecular biomarker system (MBS) to assess the physiological status of Palaomenetes pugio (grass shrimp) challenged with exposure to heat stress, cadmium, atrazine, and the water-accommodating fraction of either
diesel fuel or bunker fuel No. 2. The MBS assayed 9 specific cellular parameters of shrimp that are indicative of a nonstressed
or stressed condition: heat-shock protein 60, heat-shock protein 70, αB-crystallin homologue, lipid peroxide, total glutathione
level, ubiquitin, mitochondrial manganese superoxide dismutase, metallothionein, and cytochrome P-450 2E homologue. Using
these 9 parameters, the MBS can distinguish between the responses to each stressor, and to the nonstressed control conditions.
The MBS was able to determine the structural integrity of the cell as defined by protein turnover, protein chaperoning, and
lipid composition via lipid peroxide levels, and the status of key metabolic processes such as cytoskeletal integrity and
glutathione redox potential. This technology aids in the accurate diagnosis of the health of shrimp because the physiological
significance of changes of each parameter is well known. This technology is particularly relevant for environmental monitoring
because grass shrimp are used as key indicator species in many estuarine ecosystems. Finally, this system is easy to implement,
precise, and can be quickly adapted to an automated high-throughput system for mass sample analysis.
Received June 29, 2000; accepted February 26, 2001 相似文献
142.
多重PCR法检测对皮下和造血器官坏死杆状病毒 总被引:1,自引:0,他引:1
根据对虾皮下和造血坏死杆状病毒(HHNBV)HHNBV-XIA靶基因序列设计了4个多重PCR法用引物(P1、P2、P3、P4)。采用了五种引物组合形式分别对HHNBV-XIA、HHNBV基因和PRDV-JAPAN片段进行了物异扩增,建立了多重PCR检测HHNBV方法。通过优化多重PCR法检测HHNBV条件,可从阳性感染的中国对虾fg级DNA中定性检测出皮下和造血器官坏死杆状病毒。 相似文献
143.
对虾综合养殖围隔中浮游细菌生产力的研究 总被引:3,自引:1,他引:2
用5个养虾实验围隔研究了对虾综合养殖生态系浮游细菌的生产力。结果表明,生产量(μgC/L·d)变动在90~909之间,平均为292±141。对虾-罗非鱼-缢蛏混养及对虾-扇贝混养生态系细菌生产量相对稳定;对虾单养及对虾-缢蛏、对虾-罗非鱼混养生态系细菌生产量却变化较大。细菌生产量与水温、细菌生物量及浮游生物群落呼吸量均呈现显著相关性。细菌的日P/B系数变化在0.22~1.67(d-1)之间,平均为0.93±0.37(d-1)。细菌生产量与浮游植物毛生产量比值平均为0.15。 相似文献
144.
虾池生态系各有机碳库的储量 总被引:8,自引:0,他引:8
1997年6~8月于山东省海阳市黄海集团公司养虾场,采用围隔实验生态学方法研究了虾池生态系各有机碳库的储量,结果表明:溶解有机碳(DOC)、颗粒有机碳(POC)库储量(mgC/l)平均分别为9.95±2.04及3.10±1.60,DOC/POC比值平均为3.21.POC库中,腐质颗粒碳为总浮游生物碳的2倍.浮游植物碳、浮游动物碳、浮游细菌碳平均分别占总浮游生物碳的53%、13%及34%.腐质碳、总浮游生物碳平均分别占总有机碳(TOC)的92%及8%,腐质碳为总浮游生物碳的11.08倍. 相似文献
145.
虾池生态系能量收支和流动的初步分析 总被引:12,自引:0,他引:12
根据日本刺沙蚕作为动物性活饵在虾池食物链中的作用,对虾池生态系中的有机质收支,生物能量流动及其转化效率进行了分析。结果表明,虾池在养殖期间输入和合成的有机质能量为13725.14kJ/m^2,其中,初级产量为7523.82kJ/m^2,约占总输入的55%。有机质在养殖期间的支出量平均10359.38kJ/m^2,其中,生物呼吸7988.49kJ/m^2,占总支出的77%;对虾产量平均874.48k 相似文献
146.
147.
148.
The purpose of this study was to measure the acute toxicity of zinc (Zn) on Farfantepenaeus paulensis at different salinities and temperatures by monitoring oxygen consumption. This aspect of the effect of zinc has not been studied in this important commercial species before. First, we examined the acute toxicity of zinc in F. paulensis at 24, 48, 72, and 96?h medium lethal concentration (LC50). One hundred and fifty shrimp were employed for the routine metabolism measurement utilizing sealed respirometers. Ten shrimp were subjected to oxygen consumption measurements in one of the four concentrations of zinc (control, 0.5, 1.0, 2.0, and 3.0 mg?L?1) at three salinities (36, 20, and 5) and three temperatures (25°C, 20°C, and 15°C). Zinc was significantly more toxic at a salinity of 5 than at 20 or 36. The oxygen consumption was estimated through experiments performed on each of the 12 possible combinations of three temperatures (25°C, 20°C, and 15°C) and three salinities (36, 20, and 5). The shrimp showed a significant reduction in oxygen consumption at a salinity of 5. The results show that the oxygen consumption decreases with respect to the zinc concentration in all temperatures studied. At the highest zinc concentration employed (3.0?mg?L?1), the salinity 5 and the temperature at 25°C, oxygen consumption decreases 60.92% in relation to the control. The results show that zinc is more toxic to F. paulensis at lower salinities. The significance of the findings for the biology of the species close to sources of zinc is discussed. 相似文献
149.
Ángel Urzúa Guillermo Guerao Jose A. Cuesta Guiomar Rotllant Alicia Estévez Klaus Anger 《Marine and Freshwater Behaviour and Physiology》2013,45(6):381-397
Palaemonetes zariquieyi, an endemic palaemonid species of shrimp that lives in freshwater and brackish coastal habitats in eastern Spain, shows an abbreviated, non-feeding larval development comprising only three zoeal stages. To identify the endogenous bioenergetic fuel that allows for food-independent development from hatching to metamorphosis, larvae were reared under controlled laboratory conditions, and ontogenetic changes in dry weight (W), elemental (CHN), and lipid composition (total lipids, principal lipid classes, and fatty acids [FA]) were quantified at the onset of each zoeal stage and in the first juvenile. Values of W, C, and H per larva and per mass unit of W decreased throughout the time of larval development, while the N content showed only a weak decline (suggesting strong lipid but only little protein degradation). Correspondingly, directly measured values of total lipids (both in μg/larva and in % of W) decreased gradually, with neutral lipids (NL) consistently remaining the predominant and most strongly used fraction; sterol esters and waxes were not detected. In contrast to the NL, the fraction of polar lipids (PL) per larva remained stable and, as a consequence, tended to increase as a percentage of total lipids. Likewise, other important lipid fractions such as free FA and cholesterol remained stable throughout the time of larval development. Among the FA, palmitic (16:0), oleic (18:1n–9), linoleic (18:2n–6), and eicosapentaenoic (20:5n–3) acid were predominant, showing a significant decrease during larval development; stearic (18:0), vaccenic (18:1n–7), and arachidonic acid (20:4n–6) were found only in small amounts. Our results indicate that the lecithotrophic development of P. zariquieyi is primarily fuelled by the utilization of lipids (especially triacylglycerides and other NL), which is reflected by a decreasing carbon content. Proteins and PL, by contrast, are preserved as structurally indispensable components (nerve and muscle tissues, cell membranes). The abbreviated and non-feeding mode of larval development of P. zariquieyi may have an adaptive value in land-locked freshwater habitats, where planktonic food limitation is likely to occur. The patterns of reserve utilization are similar to those previously observed in other palaemonid shrimps and various other groups of decapod crustaceans with lecithotrophic larvae. This suggests a multiple convergent evolution of bioenergetic traits allowing for reproduction in food-limited aquatic environments. 相似文献
150.
T. J. Markwell 《New Zealand journal of zoology.》2013,40(3):231-237
Abstract Video camera technology is an increasingly common tool in the study of burrow‐dwelling animals. A camera used to observe the inhabitants of narrow burrows on Takapourewa (Cook Strait, New Zealand) is described. Population densities (animals per m2) of up to 1.1 for fairy prions {Pachyptila turtur), 0.06 for sooty shearwaters (Puffinus griseus), and 0.15 for tuatara (Sphenodon punctatus) were estimated in four different habitats. These data are similar to other estimates collected in more labour intensive studies on the island, and provide baseline information for future conservation work on Takapourewa. 相似文献