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池养长毛对虾体长与体重的关系 总被引：5，自引：0，他引：5
本文报道池养长毛对虾体长在６．８－１２３．９ｍｍ范围内的体长与体重的关系。池养长毛对虾雌、雄群体的生长特点是雌虾快于雄虾。由雌雄混合、雌虾、雄虾群体的体重对体长的相关曲线都很接近。 相似文献
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This study showed Iethal concentrations (LC) of copper for Peneaus penicillatus at various stages ofits Iife cycle were 1000μg/L for nauplii, 1000μg/L for Zoea I, 2000μg/L for Zoea Il, 2500μg/Lfor Zoea III, 3000μg/L for Mysis I, II and III and that for almost 100% mortality for postlarvae was3000μg/L. For cadmium LC were 100μg/L for nauplii, 500μg/L for Zoea l, 1000μg/L forZoea II, 2000μg/L for Zoea III, 2500μg/L for Mysis I and 3500μg/L for Mysis II, III andpostlarvae. For tmixture of both metals, LC were 400μg/L for nauplii, 1000 μg/L for nauplii, 1000μg/L for Zoea I,2000μg/L for Zoea II and 3000μg/L for Mysis I, II, III and post larvae. 相似文献
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氨对长毛对虾幼体的毒性 总被引：4，自引：0，他引：4
氨对长对虾各期幼体的毒性试验表明：蚤状幼体对氨最每天敏感，而仔虾幼体对氨的耐受性最强，在盐度３２，ＰＨ８．２０，水温２９．０℃时，无节幼体Ⅱ期，蚤状幼体Ⅰ期，仔虾第五天２４ｈ的ＬＣ５０值分别为１３．２０（１．１５）、９．９７（０．８７）、２６．９９（２．３５）和６０．８１ｍｇ／ｄｍ＾３ΣＮＨ＾＋４（ＮＨ３）－Ｎ＾１（５．３０ｇｍ／ｄｍ＾３ＮＨ３－Ｎ）．Ｚ１，Ｍ１，Ｐ５的４８ｈ的ＬＣ５０值分别为５． 相似文献
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长毛对虾酸性磷酸酶功能基团的研究(Ⅱ) 总被引：1，自引：0，他引：1
用化学修饰剂pCMB、NBS、K试剂修饰长毛对虾Penaeuspenicilla－tusAlcock酸性磷酸酶（ACPase，EC3．1．3．2），在修饰剂作用下，酶活力明显下降，健康虾酶对修饰剂的敏感性（NBS除外）大都稍大于病虾酶。修饰酶的紫外280um吸收光谱以及荧光340um发射光谱的变化，表明酶活力下降的同时酶构象也产生相应的变化。结果表明，酶分子的半胱氨酸残基、色氨酸残基以及门冬氨酸、谷氨酸β或γ验基与酶活力有关，是酶的催化功能基团。 相似文献
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《African Journal of Marine Science》2013,35(2):125-135
Due to the presence of few dominant predators on South African rocky shores, this coastline could be vulnerable to invasion by predatory crabs. This study applied horizon scanning to create an ordered watch list of alien crab species that could establish along this coastline under present-day and future temperature scenarios. This was done by: (i) identifying the species with both an invasion history and a possible pathway to South Africa; (ii) comparing the temperature ranges of the species’ native and introduced distributions to those of each of the four South African ecoregions; and (iii) ranking the species based on their potential ecological impacts. Of the 56 alien predatory crab species known worldwide, 28 species have pathways to South Africa. Incompatible temperature ranges excluded only two species from each ecoregion. Negative ecological impacts in their invaded ranges placed Japanese shore crab Hemigrapsus sanguineus, brush-clawed shore crab H. takanoi and Chinese mitten crab Eriocheir sinensis at the top of the watch list. This study highlights that many alien crab species have the potential to reach South Africa, with most likely to survive. This watch list should be used to support targeted monitoring and so facilitate early detection of these species, should they reach South Africa. 相似文献
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Temporal variation in cannibalistic infanticide by the shore crab Hemigrapsus oregonensis: implications for reproductive success 
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下载免费PDF全文 Larvae of benthic marine organisms are released amid high densities of suspension feeding and predatory adults and are highly subject to being consumed, even by conspecifics or their own parent. During laboratory feeding trials conducted in June 2006, female shore crabs (Hemigrapsus oregonensis) from Stege Marsh in San Francisco Bay (37°54.530′ N, 122°19.734′ W) that released their larvae during the previous 24 h ate fewer conspecific larvae than females that had not recently released larvae, though the behavior was not repeated during similar trials in 2007. Additionally, the number of larvae eaten increased with increasing starvation time, and hungrier females showed a trend toward eating more larvae from a different species (Carcinus maenas) than larvae of conspecifics. Thus, suppression of suspension feeding may reduce conspecific predation of newly released larvae, but this response partially depends on hunger level. This is the first time crabs have been shown to suppress feeding to reduce cannibalism of larvae, and this behavior could affect reproductive success and population dynamics. 相似文献
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利用水平淀粉凝胶电泳方法对方蟹科肉球近方蟹,绒螯近方蟹及平背蜞进行遗传分析,计检测了１１ 种同工酶,１６ 个位点。结果表明,三种蟹类的多态座位比例分别为：０．１８８,０．０６３,０．０６３;平均杂合度分别为：０．００９,０．００１,０．０４４。肉球近方蟹、绒螯近方蟹间的根井遗传距离为１．０８０。平背蜞与肉球近方蟹、绒螯近方蟹的根井遗传距离分别为１．７１７ 和１．７０７ 相似文献