Autotomy and Regeneration of Appendages in Crustaceans:A Review

Autotomy of appendages is a self-protection mechanism in crustaceans,which is defined as the reflexive loss of a limb in response to predation,competition,or other environmental factors.Single-limb injuries were the most common among the species surveyed in the present study,and the chelicerae were the most frequently lost appendages.After autotomy,hormones and signaling pathways are altered.Loss of limbs can affect foraging efficiency,although cheliped loss may be compensated by shifting to alternative prey or using both motor and oral appendages.In heterogeneous species,the loss of the major chelae may affect the selectivity of feeding.Autotomy can affect crustacean growth by reducing size increases at molting and altering the timing of ecdysis.In commercial production,removing chelicerae is an effective strategy to reduce cannibalism,and production of soft-shell crabs can be increased via autotomy.After autotomy,a new limb will regrow through regeneration and molting.This process involves the regulation of hormones,regrowth of nerves,and a number of signaling pathways that include the Wnt/β-catenin signaling pathway and transforming growth factorβsignaling pathway.Crustaceans are somewhat different from vertebrates in terms of regeneration.This review provides theoretical guidance about autotomy and regeneration applied in artificial aquaculture,and we offer several suggestions for future research on autotomy and regeneration in crustaceans.

Overview and Graph Theory of the Immune System of Crustacean

In this paper,different kinds of enzymes,immune factors and regulatory factors of the immune system of crustaceans are summarized and then combed systematically and thoroughly. According to the mutual influence and effects of these factors,different symbolic forms are introduced to express the effects,and ultimately the whole node graph of the system is obtained. The graph theory can be used for further researches on the immune system of crustacean.

Genetic Determination and Exogenous Influence in Sex Differentiation in Crustacean

The mechanisms of sex determination and the influence of exogenous factors on sex differentiation in crustacean were reviewed in the paper.Most of crustecea have not obviously sex chromosome.Androgenic gland was reported as the most important sex differentiation factors,implanting or cuting AG can change the sexal characterization of larval in crustacean.Although sex differentiation of crustacean is determined by gene,it is affected by exogenous factors such as parasite,photoperiod,temperature or hormone.Most cultured species have different body weight and length between male and female,this can be used in aquaculture to produce all male or female crusteceans to improve the production.

Research advances in the biological characteristics of the crustacean spermatozoa

The biological characteristics of crustacean spermatozoa is important for the artificial reproduction and genetic breeding. With reference to the latest studies and related materials, this paper reviewed the research progress in the biological characteristics of crustacean spermatozoa, such as morphological structure of sperm, spermatogenesis, sperm viability, preservation in vitro and acrosome reaction et al. The prospects of the research field have also been anticipated.

Seasonal dynamics of crustacean zooplankton community structure in Erhai Lake, a plateau lake, with reference to phytoplankton and environmental factors

The seasonal dynamics of a crustacean zooplankton community in Erhai Lake was investigated from May 2010 to April 2011. In total, 11 species were recorded, including six(6 genera) cladoceran and five(5 genera) copepod species. The crustacean zooplankton densities ranged from 24.3 to 155.4 ind./L. In winter and spring, the large-bodied cladoceran Daphnia galeata dominated the crustacean plankton community. In summer and autumn, when the colonial or filamentous algae dominated the phytoplankton communities, the small-bodied species(e.g. B osmina fatalis, Ceriodaphnia quadrangular, and Mesocyclops leuckarti) replaced the large-bodied ones. One-way ANOVA and redundancy analysis revealed that community structure was dependent upon total nitrogen, total phosphorus, water temperature, transparency, and the biomass of small algae. The variation in both phytoplankton structure and environmental variables were important factors in the seasonal succession of crustacean zooplankton structure in Erhai Lake.

Effects of temperature and salinity on the development of the amphipod crustacean Eogammarus sinensis

The amphipod crustacean Eogammarus sinensis has useful features that make it suitable for use in the aquaculture of fish and large decapod crustaceans.In this study,we investigated the effects of temperature and salinity on the development,fecundity,survival,and growth rate of E.sinensis.The results show that temperature significantly affected E.sinensis development,but salinity.As temperature increased,the duration of E.sinensis embryonic development decreased.Fecundity was affected significantly by temperature and the combination of temperature and salinity,but by salinity alone.In addition,high temperatures accelerated E.sinensis juvenile growth rates,whereas high salinity reduced it.Therefore,our data suggest that E.sinensis tolerates a wide range of salinities and that temperature has more significant effects than salinity on the embryonic development,fecundity,and growth of E.sinensis.Our results shall be useful for mass production of this species for use in aquaculture.

A Review of Sexual Determination and Differentiation in Crustacean

The prerequisite for monosex culture is to elucidate the molecular mechanism of sex determination and differentiation in crustaceans, as well as to explore the key genes that play a role in this process. Monosex culture technology based on crustacean economic species is of great importance in terms of genetic breeding and economic benefits of aquaculture. As a result, study into the mechanisms of sex determination and differentiation in crustaceans not only contributes to the current absence of basic theories of crustacean sexual mechanism, but also encourages technical innovation in aquaculture to increase overall economic efficiency. This study synthesizes and evaluates available research on sex determination and differentiation in crustaceans, and then provides recommendations for future research objectives and priorities in the field.

Negative effects of Microcystis blooms on the crustacean plankton in an enclosure experiment in the subtropical China

Effects of Microcystis blooms on the crustacean plankton were studied using enclosure experiments during July-September, 2000. Eight enclosures were set in the hypereutrophic Donghu Lake. Different nutrient concentrations through additional nutrient and sediment in enclosures were expected to result in different abundance of Microcystis. From July to early August, the phytoplankton community was dominated by Chlorophyta, Cryptophyta, Bacillariophyta and Cyanophyta other than Microcystis aeruginosa. M. aeruginosa showed a rapid increase during early August in all enclosures and predominated. Crustacean plankton was dominated by the herbivorous Moina micrura, Diaphanosoma brachyurum and Ceriodaphnia cornuta, and the predaceous Mesocyclops sp. and Thermocyclops taihokuensis. During the pre-bloom period, the dynamics of M. micrura population appeared to be mainly affected by the predaceous cyclopoids. With the development of Microcystis blooms, such interaction between M. micrura and cyclopoids seemed weakened, especially when the Microcystis biomass was high. But there was no apparent influence on the interaction between Leptodora kindti and its zooplanktonic prey. The density of two cyclopoids decreased with the enhancement of Microcystis. The density decline of M. micrura was caused by both predation and inhibition by Microcystis. The low food availability of other edible phytoplankton during the blooms led to low densities of both C. cornuta and D. brachyurum by late August. It appears that dense Microcystis blooms exert strong negative effects on the herbivorous cladocerans and the predaceous cyclopoids.

Controlling of crustacean zooplankton reproduction in biological activated carbon (BAC) filters by strengthen operation and management of conventional process

To counter the mass reproduction and penetration of crustacean zooplankton in Biological Activated Carbon(BAC)filters which may result in the presence of organisms in potable water and water pollution,this paper analyzed the factors affecting organisms' reproduction in BAC filters.A comparative study was performed on the density and composition of crustacean zooplankton of the concerned water treatment units of two advanced water plants(Plant A and B)which with the same raw water and the same treatment technique in southern China.The results obtained show that the crustaceans' density and composition was very different between the sand filtered water of Plant A and Plant B.which Harpacticoida bred sharply in the sediment tanks and penetrated sand filter into BAC filters was the primary reason of crustaceans reproduce in BAC filters of Plant A.For prevention of the organisms reproduction in BAC,some strengthen measures was taken including pre-chlorination,cleaning coagulation tanks and sediment tanks completely,increasing sludge disposal frequency to stop organisms enter BAC filters,and the finished water quality was improved and enhanced.

Hox genes and study of Hox genes in crustacean

Homeobox genes have been discovered in many species. These genes are known to play a major role in specifying regional identity along the anterior-posterior axis of animals from a wide range of phyla.The products of the homeotic genes are a set of evolutionarily conserved transcription factors that control elaborate developmental processes and specify cell fates in metazoans. Crustacean, presenting a variety of body plans not encountered in any other class or phylum of the Metazoa, has been shown to possess a single set of homologous Hox genes like insect. The ancestral crustacean Hox gene complex comprised ten genes: eight homologous to the hometic Hox genes and two related to nonhomeotic genes presented within the insect Hox complexes. The crustacean in particular exhibits an abundant diversity segment specialization and tagmosis. This morphological diversity relates to the Hox genes. In crustacean body plan, different Hox genes control different segments and tagmosis.

甲壳类水产品致敏原及特异性免疫制品的研究进展

甲壳类水产品是我国常见的致敏食物之一,除了规避致敏食物的摄入,目前仍无有效的根治方法。因此,致敏原的性质分析及防控技术方法的研究至关重要。本文针对甲壳类水产品致敏原,介绍了致敏原的免疫学特性与分子结构,归纳了致敏原的抗原表位,探讨了应用于致敏原特异性治疗的免疫制品,比较了不同免疫制品的作用机理及优缺点,可为研发水产品过敏的防控技术方法提供参考。

Behavioral plasticity, behavioral syndromes and animal personality in crustacean decapods： An imperfect map is better than no map

Despite their key role as model organisms in many behavioral studies, crustacean decapods have been only slightly touched upon by the recent surge of scientific interest in animal personality. Only seven articles investigated the issue in a handful of species among hermit crabs, crabs, and crayfish. Obviously, a limited number of publications does not mean that personality is rare in decapods. On the contrary, few studies might be the result of a form of reluctance by behavioral ecologists to deal with such a phenomenon in these and other invertebrates. This reluctance contrasts with the enthusiasm shown in tackling the beha- vioral plasticity issue. Here we discuss the possible theoretical and methodological difficulties raised by applying the animal per-sonality perspective to decapods and analyze implications of personality studies for their ecology, conservation, and welfare. By highlighting gaps in knowledge and directions of future research, our intention is to increase scientific emphasis on the issue.

Evolution of sex determination in crustaceans

Sex determination(SD)involves mechanisms that determine whether an individual will develop into a male,female,or in rare cases,hermaphrodite.Crustaceans harbor extremely diverse SD systems,including hermaphroditism,environmental sex determination(ESD),genetic sex determination(GSD),and cytoplasmic sex determination(e.g.,Wolbachia controlled SD systems).Such diversity lays the groundwork for researching the evolution of SD in crustaceans,i.e.,transitions among different SD systems.However,most previous research has focused on understanding the mechanism of SD within a sin-gle lineage or species,overlooking the transition across different SD systems.To help bridge this gap,we summarize the understanding of SD in various clades of crustaceans,and discuss how different SD systems might evolve from one another.Furthermore,we review the genetic basis for transitions between different SD systems(i.e.,Dmrt genes)and propose the microcrustacean Daphnia(clade Branchiopoda)as a model to study the transition from ESD to GSD.

Diel vertical migration of dominant planktonic crustaceans in the south branch of Yangtze Estuary,China

Zooplanktons are important food organisms of fishes,and their spatial and temporal distribution pattern has an important influence on the growth and reproduction of fishes in local habitats.The Yangtze River Estuary of China is rich in fishery resources,but the knowledge on the distribution pattern of zooplankton in this area is still very limited.The diel vertical migration(DVM)patterns and seasonal variations of the crustacean community,and their relationship with environmental factors were investigated in the south branch of the Yangtze Estuary,from June 2017 to May 2018.The results showed that the dispersion patterns of dominant crustacean taxa in the Yangtze Estuary were mostly aggregated.Migration amplitudes of crustacean were greater in spring and summer than in autumn and winter,and different migratory patterns occurred in different seasons.Sinocalanus dorrii,Schmackeria inopinus,Mesmackeria leuckarti,Bosmina longirostris,and B.fatalis,unlike S.forbesi,showed a significant DVM.The DVM patterns of crustaceans was possibly influenced by light dentisy,temperature,and total dissolved solids in the water column,and the fish predation effect;whereas,the nutrient concentration and pH were not supposed to be key factors.

Effects of latitude gradient and seasonal variation on the community structure and biodiversity of commercially important crustaceans in the Yellow Sea and the northern East China Sea

To evaluate the spatio-temporal variations in the community structure and biodiversity of commercially important crustaceans in the Yellow Sea and the northern East China Sea(NECS),the seasonal and regional changes in species composition,biomass structure,biodiversity and distribution of commercially important species were analyzed using bottom trawl survey data during 2014-2015.The results showed that the latitudinal gradient was obvious in species richness,dominant species and biodiversity.The indices of biodiversity increased with the decreasing latitude.When the sampling sites shifted south by one latitudinal degree,Margalefs richness index(D),Pielou's evenness index(J')and Shannon-Wiener diversity index(H')increased by 0.10.0.03 and 0.09,respectively.The biomass proportion of the cold-temperate species represented by Crangon affinis declined with the decreasing latitude,and the warm-temperate species represented by Ovalipes punctatus and Portunus trituberculatus in creased.Because of the growth regulatio n of crustaceans and the fishing moratorium,the biomass of commercially important crustaceans in the Yellow Sea and NECS was highest in October and August,respectively.Salinity had a more significant influence on H'of commercially important crustaceans than other environmental factors(including zooplankton density,sea bottom temperature and water depth).Overall,the results of this study contribute to a better understanding of community dynamics of crustaceans in the Yellow Sea and NECS,and provide evidence to verify the latitudinal gradient theory in biodiversity.

水生甲壳动物性外激素研究现状与发展方向

性外激素参与水生甲壳动物交配前识别与配偶选择。了解水生甲壳动物性外激素的化学特性对于解析其繁殖过程中化学通讯机理至关重要。对于蜕壳交配的物种而言,分析其交配和蜕壳阶段分泌的化学物质将有助于解读水生甲壳动物性外激素的演化。水生甲壳动物性外激素分为距离性外激素和接触性外激素两种,前者为水溶性的化合物;后者不溶于水,存在于甲壳动物体表。近年来,尿苷-5’-三磷酸,尿苷-5’-二磷酸和N-乙酰基-氨基-1,5-葡糖胺被认为是十足目甲壳动物距离性外激素的主要组分,而接触性外激素则由亲脂性碳氢化合物组成。近年来关于甲壳动物性外激素化学特性研究取得了长足发展,但仍存在需要突破的瓶颈。文章梳理了水生甲壳动物性外激素研究进展及未来研究方向,以期为研究水生甲壳动物性外激素提供参考。

浙江近海甲壳类资源增殖放流现状研究

甲壳类作为增殖放流的重要组成部分,可以有效地养护、补充自然海域的渔业资源。文章基于2017-2021年浙江省甲壳类增殖放流数据及相关文献资料,系统梳理了甲壳类放流种类与数量、放流资金等的年间变化趋势及放流海域、放流规格的空间、数量分布,结果显示:浙江省2017-2021年甲壳类增殖物种有日本对虾(Penaeus japonicus)、三疣梭子蟹(Portunus trituberculatus)、中国对虾(Penaeus chinensis)等6个种类,共计放流522045.5万只,投入资金3320.2万元,其中放流量、投入资金最多的是日本对虾,放流量最少的是拟穴青蟹,投入资金最少的是葛氏长臂虾,放流区域涉及温州、宁波、台州、舟山等市,各区域间的放流布局不平衡,且主要集中在小、中规格。文章将对浙江近海甲壳类放流物种存在的效果评估工作不足、个别增殖物种放流效果不佳、甲壳类放流储备物种少等问题提出针对性建议,以期为今后完善科学的增殖放流管理提供依据。

甲壳生物质修复废弃煤矿酸性矿坑水研究进展

废弃高硫煤矿酸性矿坑水(Acid mine drainage,AMD)污染是我国生态文明建设面临的重大挑战。研发低成本、可持续环境功能材料对AMD进行绿色低碳修复已成为重大科技需求。甲壳生物质富含碳酸钙、甲壳素和蛋白质,且来源广泛,利用率低。利用甲壳生物质制备修复材料治理AMD体现了“以废治废”的理念。文章综述了虾蟹壳作为修复材料治理AMD的研究现状,结果表明:虾壳既可作为碱性材料中和AMD的酸度,也可作为有机基质促进微生物的代谢活性。此外,虾壳提取物甲壳素及其衍生物壳聚糖具有丰富的羟基、氨基等官能团,可与AMD中重金属离子形成配位络合物。虾壳是具有应用前景的废弃煤矿AMD多功能修复材料。虾壳中甲壳素的绿色提取技术及其在矿区实际条件下的修复应用将是今后研究的前沿和重点。

拟除虫菊酯类杀虫剂对养殖甲壳动物毒性影响的研究进展

菊酯是杀灭无脊椎动物害虫的有效成分,具有高效性、广谱性和低毒性等特点,可分为天然菊酯(除虫菊素)和合成菊酯(拟除虫菊酯)[1]。拟除虫菊酯类杀虫剂包括:氯菊酯、氯氰菊酯、溴氰菊酯、氯氟氰菊酯、胺菊酯、氰戊菊酯、醚菊酯、甲氰菊酯等[2]。目前,拟除虫菊酯类杀虫剂的应用范围逐渐扩大。作为开发的新型农药,其被广泛应用于我国农业种植、水产养殖以及相关日常生活用品生产中[3]。随着河流运输和大气沉降等迁移过程.

美拉德反应影响甲壳类水产品致敏原致敏性的研究进展

甲壳类水产品因其丰富的营养价值而广受欢迎,但其可引起严重的过敏反应;致敏原的存在是制约甲壳类水产食品消费市场进一步发展的主要因素之一。美拉德反应广泛发生于水产品等食品加工及贮藏过程中,可影响食物的致敏性。本文首先对美拉德反应方法进行系统介绍;同时,从结构和抗原表位的角度阐述甲壳类水产品致敏原的研究进展;在此基础上,着重对甲壳类水产品致敏原经美拉德反应处理后致敏性变化及其作用机理进行综述。旨在为美拉德反应用于甲壳类水产品致敏性控制与消减提供参考。