Chinese Horseshoe Crab Tachypleus Tridentatus Research Articles

Effects of copper supplement on the immune function and blood-chemistry in adult Chinese horseshoe crab Tachypleus tridentatus

Oxygen in hemocyanin binds to copper ions and turns the hemolymph of horseshoe crabs blue. Copper ions not only transport oxygen but also enhance the immune function of horseshoe crabs. A 28-day indoor culture experiment was conducted to study the effects of adding different levels of copper amino acid chelate (0, 50, or 100 mg kg−1) into semi-finished feed on the nonspecific immune enzyme activity and hemolymph biochemical parameters of Tachypleus tridentatus. Results revealed that the activities of serum antioxidant enzyme indicators, namely, copper–zinc superoxide dismutase (Cu/Zn-SOD), catalase (CAT), glutathione peroxidase (GPX), total antioxidant capacity (T-AOC), lysozyme (LZM), alkaline phosphatase (AKP), and acid phosphatase (ACP), of copper-fed adult horseshoe crabs increased; on the other hand, malondialdehyde (MDA) activity decreased. Hemolymph biochemical indicators, triglyceride (TG) and cholesterol (CHO) decreased in the copper-fed group, but hemocyanin concentration (HC) levels increased during the experiment. At the end of experiment, all antioxidant enzymes and blood biochemical indicators in the copper-fed group were significantly different from those without copper supplement. Hemolymph T-AOC, MDA, AKP, ACP values in the low-level copper group (50 mg kg−1) were significantly different from those in the high-level copper group (100 mg kg−1).

Socio‐demographic drivers and public perceptions of consumption and conservation of Asian horseshoe crabs in northern Beibu Gulf, China

Abstract Overharvesting Asian horseshoe crabs for food is a primary threat to their populations. In the present study, 451 residents were interviewed from the northern Beibu Gulf, the coastal area that is believed to accommodate the highest density of the Chinese horseshoe crab Tachypleus tridentatus worldwide, to obtain baseline information on their consumption behaviour and underlying drivers. Based on the survey data, it is estimated that a mean individual consumption rate of ten meals per year. Nearly half of the respondents (49.7%) claimed that they had previously eaten at least two horseshoe crab meals. Among the six occupation categories (managers, professionals, workers, environmental‐related workers, fishers and farmers, and students), fishers and farmers were identified as the group that had eaten a significantly higher number of horseshoe crab meals, had consumed them more frequently, and had a greater intention of eating them than that of students. The age, education level, and salary of participants were the important socio‐demographic variables related to their consumption behaviour. More than one‐third of respondents decided to consume horseshoe crabs because they perceived them as tasty ‘seafood’ and valuable ingredients of traditional Chinese medicine. Eighty‐three per cent of participants reported an overall decrease in the number of horseshoe crabs in the region. Although the community was supportive towards horseshoe crab conservation, their ecological knowledge of horseshoe crabs was limited. The findings may be useful for providing insights to merge the gap between scientific data and management planning for the horseshoe crab population in the region. Conservation management initiatives, such as the involvement of fishers in monitoring and enforcement, developing a reporting system for landings and by‐catch, and implementing long‐term conservation education through the school curriculum could promote the protection and management of the population.

基于MAXENT模型评估北部湾潮间带中国鲎和圆尾鲎稚鲎的潜在地理分布及种群保育对策

PDF HTML阅读 XML下载 导出引用 引用提醒 基于MAXENT模型评估北部湾潮间带中国鲎和圆尾鲎稚鲎的潜在地理分布及种群保育对策 DOI: 10.5846/stxb201805161079 作者: 作者单位: 1水产科学国家级实验教学示范中心(上海海洋大学) 201306 2海洋生物科学国际联合研究中心(上海海洋大学)，中国科学技术部 201306 3上海水产养殖工程技术研究中心(上海海洋大学) 201306,广西壮族自治区水产科学研究院,天津市一瑞生物工程有限公司,上海海洋大学信息学院,1水产科学国家级实验教学示范中心(上海海洋大学) 201306 2海洋生物科学国际联合研究中心(上海海洋大学)，中国科学技术部 201306 3上海水产养殖工程技术研究中心(上海海洋大学) 201306,1水产科学国家级实验教学示范中心(上海海洋大学) 201306 2海洋生物科学国际联合研究中心(上海海洋大学)，中国科学技术部 201306 3上海水产养殖工程技术研究中心(上海海洋大学) 201306 作者简介: 通讯作者: 中图分类号: 基金项目: 香港海洋公园保育基金（OT03.1617）；2017北海市"十三五"海洋经济创新发展示范项目（Bhsfs006） Prediction of potential distribution areas of Chinese horseshoe crab and mangrove horseshoe crab in the Beibu Gulf of Guangxi based on MAXENT model and their population conservation strategies Author: Affiliation: National Demonstration Center for Experimental Fisheries Science Education,Shanghai Ocean University,Shanghai,,,,National Demonstration Center for Experimental Fisheries Science Education,Shanghai Ocean University,Shanghai,National Demonstration Center for Experimental Fisheries Science Education,Shanghai Ocean University,Shanghai Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:鲎具有极高的经济价值和科研意义。近年来由于过度捕捞和栖息地受损等原因，亚洲鲎种群数量正急剧下降。鲎漫长的生命周期使得鲎资源的保护和增殖迫在眉睫。生态位模型已经广泛应用于物种的潜在地理分布预测。基于实地调研数据和公开发表的北部湾中国海域中国鲎和圆尾鲎地理分布数据，运用MAXENT模型得到中国鲎和圆尾鲎在广西北部湾（中国部分）的栖息地适宜度指数（Habitat suitability index，HSI），确定了这两种稚鲎在北部湾中国海域潜在适生区。模型分析结果表明，潮间带坡度和地形指数是影响中国鲎分布的主要环境因子，而潮间带底质的有机物含量和植被指数是影响圆尾鲎分布的主要环境因子，根据研究结果建议在两种稚鲎适生区建立保护区，进行人工放流稚鲎，加强对海草和红树林的生态建设，进而促进鲎资源种群恢复和发展。 Abstract:Horseshoe crab has high economic and scientific values. In recent years, because of overfishing and habitat degradation, the population of horseshoe crabs in China is decreasing rapidly. However, their long life cycle makes it extremely urgent to protect horseshoe crabs. Ecological niche models have been widely applied to predict the potential geographic distribution of species. The habitat suitability index of the Chinese horseshoe crab Tachypleus tridentatus and mangrove horseshoe crab Carcinoscorpius rotundicauda in the Beibu Gulf (Chinese part) was determined by using the maximum entropy model and the distribution of habitat suitability of the two types of juvenile horseshoe crab in the Beibu Gulf was determined based on field survey data and published data on the geographical distribution of two horseshoe crab species in the Beibu Gulf. The model analysis results showed that the slope of the intertidal zone and topographic index were the main environmental factors affecting the distribution of the Chinese horseshoe crab, while the organic content and vegetation index of intertidal sediment were the main environmental factors affecting the distribution of the mangrove horseshoe crab. According to the results, to promote the recovery and development of horseshoe crab resources, protected areas should be established, artificial release of juvenile horseshoe crabs in habitat suitability areas of horseshoe crab should be conducted, and the ecological construction of seagrasses and mangroves in these areas should be strengthened. 参考文献 相似文献 引证文献

Fatty acids from controlled feeding as dietary markers of juvenile Chinese horseshoe crab, Tachypleus tridentatus

The potential use of fatty acid (FA) profile as a dietary tracer in juvenile Chinese horseshoe crab Tachypleus tridentatus was assessed in a feeding experiment. Selected feed was provided to the juveniles at various growth stages according to their food sources in the wild: larval and adult brine shrimp Artemia salina for the first six months, followed by a mixture of short-neck clam Ruditapes philippinarum and greasyback shrimp Metapenaeus ensis for a further six months. Juvenile horseshoe crab haemolymph and tissues of book gill, opisthosomal spine, chelicera and swimming leg were sampled after the feeding experiment. The FA profiles revealed that the juvenile haemolymph and various tissues had a total of 23–24 FA components. The major FA components consisted of saturated (palmitic and stearic) at 22–34%, monosaturated (oleic) at 7–34% and polyunsaturated (eicosapentaenoic and arachidonic) FAs at 9–27%. According to principal component analysis, the FA signatures of juvenile haemolymph were greatly influenced by the shift of food sources from brine shrimp to clam and shrimp meat, whereas the FA profiles of different tissues were more resistant to the nutrient alteration. The present findings confirmed that the FA profile of both juvenile haemolymph and different tissues reflected the FA composition of recent and previous diets, respectively; and thus may be useful in indicating the foraging information of juvenile horseshoe crabs in the field.

Responses of growth and hemolymph quality in juvenile Chinese horseshoe crab Tachypleus tridentatus (Xiphosura) to sublethal tributyltin and cadmium.

Responses of growth endpoints and hemolymph constituents in juvenile Chinese horseshoe crab Tachypleus tridentatus under treatments of 0.01 and 0.1 mg/l tributyltin (TBT) and 0.1 and 1 mg/l cadmium (Cd) were examined in a 12-week experiment. A significant decline in final body weight, final prosomal width, percentage of individuals molted and mean molting time was detected under TBT exposures. While morphological abnormalities of the juveniles between TBT treatments and the control were statistically indistinguishable, significantly higher occurrences of carapace erosion and appendage loss were noted under 0.1 and 1 mg/l Cd exposures. Various hemolymph quality indicators, including hemolymph plasma protein level, amebocyte viability and percentage of granular-spherical state of amebocytes of the juveniles exposed to TBT or Cd were significantly lower than the control. Such a decrease in hemolymph quality suggested deleterious effects of metal contaminant-induced stressors on the health status of the juveniles even at low exposure levels (i.e., 0.01 mg/l TBT and 0.1 mg/l Cd). Changes of hemolymph parameters in juvenile horseshoe crabs were more sensitive than growth performance as well as morphological abnormalities in response to metal stressors, and can be used as an indicator to reflect habitat conditions and contaminant levels.

Development of molecular resources for the Chinese horseshoe crab Tachypleus tridentatus

AB Aquatic Biology Contact the journal Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections AB 24:17-24 (2015) - DOI: https://doi.org/10.3354/ab00632 Development of molecular resources for the Chinese horseshoe crab Tachypleus tridentatus Hongjun Li1, Ying Xia2, Yiyong Rao4, Shuxi Liu1, Jingjing Zhang1,5, Lizhe Cai3,4,* 1Key Laboratory for Ecological Environment in Coastal Areas (SOA), National Marine Environmental Monitoring Center, Dalian 116023, PR China 2Dalian Environmental Monitoring Center, Dalian 116023, PR China 3Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, PR China 4College of the Environment and Ecology, Xiamen University, Xiamen 361002, PR China 5Dalian Ocean University, Dalian 116023, PR China *Corresponding author: cailizhe@xmu.edu.cn ABSTRACT: The Chinese horseshoe crab Tachypleus tridentatus is an endangered marine benthic species of great biomedical value and scientific significance. In this study, T. tridentatus hemocyte transcriptome was sequenced to rapidly develop molecular resources using the Illumina paired-end sequencing platform. Deep sequencing generated a total of 38402764 reads that consisted of 7.7 Gbp raw data, which were assembled into 38759 unigenes with an average length of 668.6 bp. A total of 608 microsatellite loci and 71959 high-confidence single nucleotide polymorphisms were discovered. All the assembled unigenes were annotated by running BLASTx similarity searches on Nr, Swiss-Prot, COG, and KEGG databases; of which 17446 (45.0%) unigenes showed significant matches (E-value <1e-5) to known sequences in public databases. As determined through gene ontology annotation and KEGG pathway mapping, the functional annotation of the unigenes signified diverse biological functions and processes. Transcripts potentially involved in immune defense were identified among these genes. These transcripts included pattern recognition receptors, stress response genes, complement components, and immune effectors. This study provides important insights into the transcript sequences of T. tridentatus, which may facilitate studies on the conservation genetics and development of biomedical applications for T. tridentatus. KEY WORDS: Chinese horseshoe crab · Tachypleus tridentatus · Endangered species · Transcriptome · RNA-seq · Microsatellite · SNP · Conservation genomics · Biomedicine Full text in pdf format Supplementary material 1 Supplementary material 2 PreviousNextCite this article as: Li H, Xia Y, Rao Y, Liu S, Zhang J, Cai L (2015) Development of molecular resources for the Chinese horseshoe crab Tachypleus tridentatus. Aquat Biol 24:17-24. https://doi.org/10.3354/ab00632 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in AB Vol. 24, No. 1. Online publication date: May 20, 2015 Print ISSN: 1864-7782; Online ISSN: 1864-7790 Copyright © 2015 Inter-Research.

A dual stable isotope study for diet composition of juvenile Chinese horseshoe crab Tachypleus tridentatus (Xiphosura) on a seagrass-covered intertidal mudflat

To enhance our understanding on the foraging biology of juvenile Chinese horseshoe crab on a seagrass-covered intertidal mudflat, we used dual stable isotopes δ13C and δ15N to determine the diet composition and trophic position of 6th–11th instar juveniles in summer and winter. The δ13C and δ15N values in tissues of juveniles and their potential food sources suggested that the juveniles consumed a mixed diet mainly comprised a variety of polychaetes, crustaceans and bivalves, in which these food groups were abundantly available in the study site and largely supported by seagrass biomass in both summer and winter. While δ15N values in juvenile tissues were statistically similar between the two seasons, the δ13C values in tissues of juveniles had a minimal seasonal difference which was probably due to variations in the source values rather than the changes in diet composition of juveniles. There were no differences in δ13C and δ15N values among the size groups of juveniles through 6th–11th instars. Although juvenile Chinese horseshoe crabs may consume the prey in response to the seasonal availability on the mudflat, a healthy condition of habitat with high water quality is essential to support the juveniles and a wide range of intertidal invertebrates they consume.

Hemolymph quality as indicator of health status in juvenile Chinese horseshoe crab Tachypleus tridentatus (Xiphosura) under laboratory culture

The growth performance and hemolymph quality of juvenile Chinese horseshoe crabs under four diet treatments: brine shrimp Artemia salina, short-neck clam Ruditapes philippinarum, sandworm Marphysa sanguinea and mixed clam and sandworm were evaluated in a 12-week experiment. The growth responses in terms of final body weight, specific growth rates and percentage of individuals molted under the clam diet were significantly higher than those fed with brine shrimp and sandworm, whereas the mixed clam and sandworm diet was not statistically different from the other three treatments. While the hemolymph properties among these diets were similar, significant declines in hemocyanin concentration, percentage of oxyhemocyanin, and ratio of granular–spherical to granular–flattened states of amebocytes were noted at the end of the study. Such a decrease in hemolymph quality indicated deleterious effects due to prolonged culture on the health status of the juveniles, which might be attributed to captivity-related issues, such as deficiencies of essential diet compositions, movement constraints and absence of tidal rhythms. This was further supported from the finding that the hemolymph quality of the experimental juveniles was significantly poor compared to that of the juveniles collected from the field. Changes of hemolymph constituents could thus be a useful indicator to reflect the health status of juvenile horseshoe crabs under laboratory culture.

Physiological energetics of the fourth instar of Chinese horseshoe crabs (Tachypleus tridentatus) in response to hypoxic stress and re-oxygenation

Hypoxia associated with eutrophication is a potential threat to the Chinese horseshoe crab Tachypleus tridentatus which inhabits intertidal sand flats in Asia. This study investigated the effect of dissolved oxygen level (DO) (6, 4 and 2mg O2 l−1) on the physiological energetics in the juvenile T. tridentatus. They were exposed to various oxygen levels for three days and then transferred to normoxia for three days to examine the recovery from low oxygen stress. Feeding rate, respiration rate and scope for growth were reduced at lower DO levels while absorption efficiency and excretion rate were independent of DO levels. Although full recovery of the physiological responses and scope for growth from hypoxis stress was observed when normoxia resumed, their long term survival in suboptimal habitats with frequent occurrence of hypoxia deserves a close monitoring as hypoxia may be even more common in future in a warming world.

Comparison of different frozen natural foods on survival and growth of juvenile Chinese horseshoe crabTachypleus tridentatus(Leach, 1819): implications on laboratory culture

The Chinese horseshoe crab Tachypleus tridentatus (Leach, 1819) is facing a dramatic population decline in Asia. Evaluating their survival and growth under laboratory conditions is essential to optimize their indoor culture system, particularly for future re-stocking trials in the wild. In this study, three types of frozen natural foods (brine shrimp Artemia salina, opossum shrimp Mysis relicta and chironomus larva Chironomous plumosus) were offered to juvenile Chinese horseshoe crabs T. tridentatus for 100 days in the laboratory. While feed efficiency ratio in C. plumosus treatment was significantly higher than that in A. salina and M. relicta treatments, survival rate, final body weight, thermal-unit growth coefficient and feeding rate of T. tridentatus fed with A. salina were significantly higher than those in other diet treatments. Results showed that A. salina is a more suitable food diet than M. relicta and C. plumosus for juvenile T. tridentatus under laboratory culture conditions.