Phlorizin alleviates deltamethrin-induced oxidative stress in brine shrimp Artemia

Deltamethrin(DEL),a commonly used pyrethroid pesticide,results in higher reactive oxygen species(ROS)levels in aquatic animals,which consequently unbalance the redox state.Phlorizin(PHL)is a flavonoid and a natural product promising to prevent or reduce pesticide-induced oxidative stress.Artemia is a micro-crustacean widely used in marine hatcheries and an experimental aquatic organism for environmental toxicology research.This research aimed to evaluate the toxicity of DEL on Artemia and the antioxidative effect of PHL against the toxicity.Results show that 0.08-mg/mL PHL exerted its antioxidative effects on hatching percentage of the cysts in 24-h incubation and on body length and survival rate of Artemia in 12-d culture.After 12-d culture,12-,24-,and 36-h DEL exposure showed significant drops in SOD,CAT,and GSH-Px enzyme activities,and significant increases in ROS and malondialdehyde(MDA)levels in Artemia(P<0.05).On the contrary,0.08-mg/mL PHL application improved the enzyme activities and decreased the ROS and MDA levels(P<0.05).Moreover,0.08-mg/mL PHL significantly increased mRNA expression levels of Cu/Zn SOD,CAT,GST,HO-1,NQO1,and Nrf2,and decreased mRNA expression level of Keap1 in the DEL-exposed Artemia(P<0.05).Therefore,DEL is toxic to Artemia,while PHL alleviates DEL-induced oxidative damage by possibly regulating the Nrf2signaling pathway.This study provided a theoretical basis for PHL to reduce pesticide-induced toxicity in aquatic animals.

Molecular Phylogeny of Bisexual Artemia Based on 16S rDNA

[Objective] The research aimed at investigating the taxonomic position and phylogenetic relationship of bisexual brine shrimps.[Method] 16S rDNA of three species of bisexual Artemia from China was determined;the homologous sequences between them and 11 relative species of Artemia from GenBank were compared;the molecular phylogenetic tree was constructed by Mega Microsoft using Artemiopsis stefanssoni as outgroup.[Result] Artemia persimilis was the primal group in genus Artemia;Artemia franciscana and Artemia monica were the evolved groups;Artemia urmiana,Artemia sinica and other Artemia species from China shared a close genetic relationship.[Conclusion] Based on the 16S rDNA sequence of them,the phylogenetic relationships of these bisexual Artemia species were A.persimilis→A.urmiana,A.sinica and A.tibetiana→A.tunisiana→A.monica→A.Franciscan.

Study on Hatching Rate of Artemia fanciscana Cysts in Different Sources of Saline

A comparison of Arternia cysts hatching （Artemia franciscana） were conducted on bleaching and non-bleaching with sodium hypochloride on five dilution of salt solution by using sea water, sea salt solution, artificial sea salt solutions, iodine added cooking salt solution, and rock salt solutions. All solutions were adjusted at 30 ppt of salinity in 1 litter cylinder. The experiment was carried out with Factorial Experiment in CRD. After 24 hours, a randomized count of living Artemia was taken a photograph of Artemia size by stereo microscope. A statistic analysis showed that all data of bleaching and non-bleaching were no significant difference （P 〉 0.05）. The hatching ability of Artemia cysts in solutions was examined and the results showed that sea salt solution was 327.33 × 103.4. 28,536.5263 Nauplii/liter, sea water 316 ×10^3± 20,420.5779 Nauplii/liter, artificial sea salt solutions 314.33× 10^3 ± 34,268.5473 Nauplii/liter, iodine added cooking salt solution 309.66 ± 10^3 .4- 22,898.3260 Nauplii/liter, and rock salt solutions 305.33 ± 10^3 ± 25,579.9401 Nauplii/liter, respectively. The body length of Artemia was compared and the data showed that there was no significant difference （P 〉 0.05）. The highest body length was found in sea salt solution 527.32 ± 4.70μm, sea water 521.65±8.51 μm, artificial sea salt solutions 522.08 ± 10.04 μm, iodine added cooking salt solution 522.67 ±7.87 μm, and rock salt solutions 516.33 ±11.15μm, respectively.

山东盐田及新疆盐湖卤虫(Artemia parthenogenetica)生物学测定值的比较

从山东的盐场和新疆的盐湖采集了卤虫卵,进行了干燥、吸水和去壳的卵径、壳厚、无节幼体体长、染色体数目的生物学测定。按照文献[12]的分类,上述研究的卤虫,均属于第二类的孤雌生殖品系。盐湖的卤虫卵吸水和去壳后比盐场的卤虫卵大。而达板城东盐湖的无节幼体是最短的。各盐场的卤虫有2倍体、4倍体及5倍体,艾比湖的卤虫有2倍体和4倍体,达板城东盐湖只有4倍体。

温度对中国卤虫（Artemia sinica）种群的影响

本文采用生命表和数值模型分析等方法，对中国卤虫（Ａｒｔｅｍｉａｓｉｎｉｃａ）的温度特性做了研究。１．孵化发育起始温度９．０７℃，幼虫发育起始温度９．０７℃。有效积温（℃·ｄ）前者为０．９２１±０．９７９，后者为２０５．２６±２４．１，平均世代有效积温４５８．４±３９．６。２．各项生命表参数均与温度呈显著的函数关系，其适温范围基本介于１８─３４℃，最适点介于２６．５─２８．５℃，种群增长倍数＞２的温度范围在１８─３４℃。３．在山西盐池水域，该卤虫的年世代数为６．２±０．６２个世代、第２─５个世代是种群生产力高峰期。在此期间种群的加倍时间＜１５ｄ．内禀增长率＞０．０４ｄ￣（－１）。

Impact of brine acidification on hatchability, survival and reproduction of Artemia parthenogenetica and Artemia franciscana in salt ponds, Bohai Bay, China

We studied the effect of pH （pH 5, 6, 7 and 8） on the hatching percentage, survival and reproduction of Artemia strains in Bohai Bay salt ponds. Strains included parthenogenetic Artemia from Bohai Bay （BHB）, Artemiafranciscana from San Francisco Bay, and A. franciscana artificially produced in salt ponds in Vietnam. The latter was included as a potential inoculum for biological management of salt ponds. The hatching percentage of cysts after 24 h and the survival rate of the tested Artemia strains were significantly reduced when exposed to a culture medium at pH 5 for 18 d （P〈0.05）. The tolerance of Artemia to 48 h acid exposure varied with developmental stage, increasing in the following order： juvenile, nauplii, pre-adult, with maximum tolerance in adults. All strains of Artemia tested could not reproduce at pH 5. At pH levels from pH 6-8, a higher pH generally resulted in a shorter brood interval and enhanced ovoviviparity. Hence, we suggest that brine acidification has a negative impact on Artemia populations in the Bohai Bay saltworks. Inoculation of Artemia with either local parthenogenetic Artemia or exotic A. franeiscana should be feasible at pH 7-8.

Intentional introduction of Artemia sinica(Anostraca) in the high-altitude Tibetan lake Dangxiong Co:the new population and consequences for the environment and for humans

The imbalance between supply and demand of Artemia cysts in China and around the world is increasing now.Salt lakes in Tibet may contribute to the solution of the problem.In Northern Tibet there are 26 saline lakes whose salinity and temperature may support Artemia survival at an altitude of 4 000–5 100 m.We found Artemia in 15 of these lakes.The saline lakes with Artemia populations mainly belong to the shallow basin lakes,and the majority of these lakes are small in area.The total area of lakes without Artemia is more than 1 000 km 2.Lake Dangxiong Co(Co means lake in Tibet) was chosen for the intentional introduction of Artemia sinica.In 2004,850 g of A.sinica cysts,originating from Qinghai,were introduced in the lake.Surveys in 2006–2014 showed that the average abundance of Artemia adults in the lake gradually increased from 20 ind./m 3 in 2006 to 1950 ind./m 3 in 2013.We assume that two subpopulations of A.sinica,separated by depth,may exist in the lake.The new Artemia population caused an increase in the number of species of phytoplankton and heterotrophic protozoa with a decrease of their total abundance.Water transparency also increased.Dominance in phytoplankton passed from cyanobacteria to diatoms.Changes occurred not only in the lake ecosystem;the number of water birds using the lakes also dramatically increased.Preliminary calculations showed that is it possible to harvest at least about 150 t cysts per year from the lake as well as 3.2 thousand tons of frozen or 350 t of dried biomass of adult Artemia.

Effect of carbon and nitrogen ratio control on Artemia growth, water quality, biofloc microbial diversity under high salinity and zero-water exchange culture condition

Biofloc technology has been applied successfully in the intensive aquaculture of several fish and shrimp species. The growth of heterotrophic microorganisms can be stimulated through adding extra carbon, which reduces the nitrogen level in the water and provides microbial protein to the animals. However, most of the studies and practical applications have been conducted in freshwater and marine environment. This paper focused on brine shrimp Artemia that lives in high salinity environment together with other halophilic or halotolerant microorganisms. The effect of carbon supplementation on Artemia growth, water quality, and microbial diversity of biofl ocs was studied in the closed culture condition without any water exchange. The salinity of the culture medium was 100. A 24-d culture trial was conducted through supplementing sucrose at carbon/nitrogen (C/N) ratio of 5, 15, and 30 (Su5, Su15, and Su30), respectively. The culture without adding sucrose was used as a control. Artemia was fed formulated feed at a feeding ration of 60% recommended feeding level. The results showed that sucrose supplementation at higher C/N ratio (15 and 30) signifi cantly improved the Artemia survival, growth and water quality ( P <0.05). Addition of sucrose at C/N ratio of 15 and 30 significantly increased biofloc volume (BFV)( P <0.05). The Illumina MiSeq sequencing analysis showed that supplementing carbon at C/N ratio of 15 had a better total bacterial diversity and richness, and shaped the microbial composition at genera level. This study should provide information for studying the mechanism of biofloc technology and its application in high salinity culture conditions.

Proteomic analysis of acute responses to copper sulfate stress in larvae of the brine shrimp,Artemia sinica

Proteomics was used to reveal the differential protein expression profiles of acute responses to copper sulfate exposure in larvae of Artemia sinica.Fourteen differentially displayed protein spots were detected and seven of them were identified.Three spots were up-expressed and identified:actin, heat shock protein 70,and chaperone subunit 1;three down-regulated proteins were identified:arginine kinase,elongation factor-2,and glycine-rich protein;and a newly expressed protein was identified as peroxiredoxin.The study indicates the involvement of all the differentially expressed proteins in the early responses of protein expression,and in the survival of A.sinica in the presence of copper and other heavy metals;the findings improve understanding of the organism’s adaptive responses and resistance.

THE BRINE SHRIMP (ARTEMIA PARTHENOGENETICA) AS ENCAPSULATION ORGANISM FOR PROPHYLACTIC CHEMOTHERAPY OF FISH AND PRAWN

Brine shrimp (Artrmia parthenogenetica) which had ingested three water-insoluble antibactrial drugs ie.sulfadiazine(SD), oxytetracycline (OTO) and erythromycin estolate (ERY-Es) were fed to TiIapia andMysis Ⅲ of Penaeus orientalis K..The drug contentS in the predators were then determined. Aferadministration of drugs to TiIapia and Mysis Ⅲ, through the bio-encapsulation of the brine shrimp,efficacious therapeuical concenration of OTC and ERY-Es(but not SD) in the pndators could bereached and meintained for mere than 8 hours.

Piwi基因参与两性卤虫(Artemia franciscana)的生殖调控研究

Piwi(P-element induced wimpy testis)基因编码Piwi蛋白,在生殖干细胞的自我更新、减数分裂过程、RNA沉默和转录调控中起重要作用。为探究Piwi基因参与两性卤虫生殖发育的作用,从两性卤虫Artemia franciscana转录组中筛选获得Piwi基因开放阅读框,进行序列分析和结构域预测等生物信息学分析,采用qPCR技术研究该基因在A.franciscana生殖腺发育不同时期表达特征,并利用RNAi显微注射技术探究其功能。生物信息学分析表明,A.franciscana Piwi基因的开放阅读框长2619 bp,编码872个氨基酸;Piwi基因编码的蛋白分子量为98.11 kDa,等电点为9.50,为碱性亲水性蛋白,无信号肽和跨膜结构;存在Piwi和PAZ结构域及ArgoL1结构域,二级结构以α-螺旋为主,三级结构与之对应;系统进化树显示A.franciscana与蚤状溞和大型溞的Piwi序列相似性最高。qPCR结果表明,Piwi基因在卵巢的卵黄发生晚期和晚期胚胎表达量最高,显著高于卵黄发生早期和早期胚胎(P<0.01);Piwi基因在精巢的未成熟期表达量最高,显著高于成熟早期、成熟中期和成熟晚期(P<0.01)。RNAi结果显示,该方法能显著降低Piwi基因的表达水平(P<0.01),并导致A.franciscana所产后代均为休眠卵,说明Piwi基因不但在A.franciscana生殖发育调控起重要作用,而且可能在其繁殖方式决定过程中起关键作用。研究结果为两性卤虫Piwi/piRNA功能和分子机制调控的研究提供了基础信息,将有助于揭示Piwi基因参与调控两性卤虫生殖发育机制。

EFFECT OF ARTIFICIAL REGULATIONS OF ARTEMIA n-3 HUFA CONTENT ON GROWTH AND SURVIVAL OF BLACK SEABREAM (SPARUS MACROCEPHLUS) LARVAE

The requirement for dietary n-3 HUFA (highly unsaturated fatty acid ) for growth and survival of black seabream (Sparus macrocephalus) larvae was tested using Artemia with various levels of n-3 HUFA. Four tueatments with Artemia differing in theirn-3 HUFA were prepared by feeding them various oil emulsions .The results indicated that dietary n-3 HUFA significantly influences fish n-3 HUFA levels and are necessary for good growth and survival of black seabream larvae . The proper value of n-3 HUFA level and DHA, EPA level in Artemia should be 4.273% and 0.873% (wet weight) for good growth and survival in black seabream larvae respectively.

Eff ect of polystyrene microplastics and temperature on growth,intestinal histology and immune responses of brine shrimp Artemia franciscana

Microplastics pollution and seawater temperature rise have been the major environmental issues,threatening the survival and biodiversity of marine organisms.This study evaluated the combined effect of temperature and polystyrene microplastics(MP)on Artemia,a filter-feeding crustacean that is widely used for environmental toxicology studies.Brine shrimp Artemia franciscana were exposed to three MP concentrations(0,0.2,and 2.0 mg/L)and three temperatures(22,26,and 30℃)for 14 d.In general,higher MP concentration and temperature led to a decreased survival rate and growth.Two-way ANOVA analysis indicated that the survival rate of Artemia was significantly impacted by both MP concentration and temperature(P<0.05),but there was no significant interaction between two factors(P>0.05).Growth of Artemia was significantly impacted by temperature(P<0.05),and with a significant interaction between two factors(P<0.05).Furthermore,the enzymatic activity,intestinal histological analyses,and immune gene expression were determined for Artemia reared at 30℃ with three MP concentrations(0,0.2,and 2.0 mg/L).The results showed that 2.0-mg/L MP resulted in reduced Artemia intestinal microvilli and exfoliated epithelia cells,significantly increased acid phosphatase(ACP)activity(P<0.05)and immunerelated gene ADRA1 B and CREB3 expression,revealing that higher MP concentration could induce oxidative and immunological stress on Artemia at 30℃.Overall,our study suggests that MP and temperature have combined adverse effect on Artemia,especially at relatively high temperature and polystyrene MP concentration.These findings are important to understand the potential ecological risks posed by these two factors on the organisms in marine environment.

The Occurrence of an Exotic Bisexual Artemia Species, Artemia franciscana, in Two Coastal Salterns of Shandong Province, China

The alien halophilous Artemia species, Artemia franciscana, was found in Chengkou Saltern and Yangkou Saltern of Shandong Province, P.R. China. Although the indigenous parthenogenetic Artemia is detectable, the exotic species is dominant in both salterns. The cross-breeding tests between the exotic A. franciscana and 5 bisexual Artemia species were conducted. The results of hybridization and morphological observations on the exotic A. franciscana are briefly presented in this short communication.

Partially or Totally Replacing Fish Meal with Frozen Artemia as a Dietary Protein Source for Early Stage Giant Freshwater Prawn, Macrobrachium rosenbergii Post Larvae Reared under Controlled Conditions

A 105-day feeding study was conducted to evaluate the effect of partial （0%, 20%, 40%, 60% and 80%） and complete （100%） substitution of dietary fish meal （FM） with frozen Artemia on growth performance and feed utilization of Giant freshwater prawn （Macrobrachium rosenbergii） post larvae （PL） reared in fiberglass tanks under controlled conditions. A total of 1080 M. rosenbergii PL, average weight of 6.10 ± 0.4 mg, were equally distributed over 18 fiberglass tanks, （1 m^3 each, and triplicate per treatment）. Six experimental isocaloric （14 MJ/kg/digestible energy） and isonitrogenous （35% crude protein） diets were lbrmulated. Control diet （D1, 100% FM） was formulated with FM as the main protein source （0% Artemia）. Diets D2-D6 were substituted with five dietary protein levels of frozen Artemia （20%, 40%, 60%, 80% and 100%）, respectively. Results showed that growth performance of M. rosenbergii PL fed different Artemia based diets was either equal or superior to prawn fed control FM diet. In addition, increasing dietary frozen Artemia replacement level from 20% up to 100% led to a significant （P 〈 0.05） increase in survival, growth and feed utilization, which indicate that the essential nutrient requirements needed for M. rosenbergii PL was covering with improving feed satiation of PLs. It could be concluded that frozen Artemia biomass instead of fishmeal in M. rosenbergii PL diets can improve survival rate, growth performance, feed utilization, contributing to reducing the use of FM in practical diets and the nursery phase could be shorter and more profitable.

The critical stage for inducing oviparity and embryonic diapause in parthenogenetic Artemia(Crustacea: Anostraca): an experimental study

The brine shrimp Artemia exhibits two reproductive modes: 1) oviparity, producing diapause embryos;and 2) ovoviviparity, producing free-swimming nauplii. Previous studies have suggested the existence of a critical stage that determines the reproductive mode. Physicochemical factors, such as photoperiod, temperature, and salinity, have been suggested to irreversibly aff ect the reproductive mode of oocytes during this critical stage. In this study, experiments were carried out using a photoperiod and temperature-sensitive parthenogenetic Artemia clone where maternal Artemia were shifted bidirectionally between ovoviviparity (18 h L:6 h D, 27℃) and oviparity (6 h L:18 h D, 19℃) culture conditions. In the main experiment ( Artemia shifted at six diff erent stages including the post-larva Ⅱ to adult Ⅱ), the reproductive mode of fi rst brood was converted when shifting was performed on post-larva Ⅱ and Ⅲ but was not converted when females were shifted after post-larva Ⅲ. A supplementary experiment further revealed that the reproductive mode of fi rst brood could be altered when shifting females at an "early phase of postlarva Ⅳ", characterized by a developing ovisac reaching the middle of the third abdominal segment, ventral spines, and some oocytes growing larger than the others. In both experiments, reproductive modes of the second brood were signifi cantly aff ected when the shifting was performed on post-larva Ⅳ. These results suggest that the critical stage for inducing oviparity and embryonic diapause is at the previtellogenic stage of oocytes, or at maternal "early phase of post-larva Ⅳ" for the first-brood off spring. During this stage, diff erential gene expression patterns of the two destined oocytes may be triggered by the token stimuli signals received by the oocytes.

The Biodiversity of Shrimp Genus Artemia from Russian Lakes:Morphometric,Cytogenetics and DNA-analysis

Shrimps of genus Artemia are the inhabitants of continental and marine waters with salinity of 70 to 350 g/l and above.Artemia is able to survive in the conditions in which other animals cannot exist.This is due to adaptations:effective osmoregulation system,the ability to synthesize of respiratory pigment(hemoglobin)and diapauses cysts(Litvinenko at.al.,2009).Cysts of this

Microbiota of Salt Lakes as Food for the Brine Shrimp Artemia

The brine shrimp Artemia is often abundantly found in hypersaline environments.The larvae(‘nauplii’)hatching from its dormant embryos(‘cysts’)are a crucial live food item for the larval stages of fish and shrimp in aquaculture

Results of an Intentional Introduction of Artemia sinica in the High-Altitude Tibetan Lake Dangxiong Co:On a Base of Surveys in 2011 and 2013

1 Introduction The human population is projected to reach 9200million by 2050.A fundamental question for science is whether it is possible to increase food production to meet the demands of a human population of that magnitude.It’s possible only to increase an aquaculture production.Cultivation of fish/shrimp larvae is a bottleneck in a cultivation of the different organisms.Live food

Studies on acute toxicity of three heavy metal ions to Artemia

Studies on acute toxicity of Cu2+,Mn2+and Zn2^to Artemianauplii(36h)and adults were carried out at15±3°C in the natural seawater where salinity is30using single-factor acute toxicity;on this basis,equi-toxicity test was used to evaluate the effect of joint toxicity of Cu2+,Mn2+and Zn2+to Artemia nauplii(36h)in the same conditions.Results show that Artemia has different tolerances for the three heavy metal ions when it is in different growth period,and the interaction of heavy metal ions varied with growth period,adults are more sensitive of the three heavy metals;The48h LC50of these three heavy metal to the Artemia nauplii is4.0,27.19and115.95mg/L,and to the adults is1.31,6.86and34.23mg/L;the order of toxicity of cuprum,manganese and zinc for Artemia nauplii and adults was Cu2^>Mn2+>Zn2+;the safe concentration of the three heavy metal ions(Cu2+,Mn2+and Zn2+)to Artemia nauplii(36h)and adults were0.4,2.72,11.6,0.13,0.69and3.42mg/L.The results of combined toxicity test showed that Cu-Mn,Cu-Zn and Mn-Zn were all antagonistic to the Artemia naupli.