Chinese mitten crab （Eriocheir sinensis） has higher commercial value as food source than any other species of Eriocheir in China. To evaluate the germplasm resources and characterize the genetic diversity and popula...Chinese mitten crab （Eriocheir sinensis） has higher commercial value as food source than any other species of Eriocheir in China. To evaluate the germplasm resources and characterize the genetic diversity and population structure of the crabs in different water systems, two stocks and two farming populations were assessed with 25 polymorphic microsallite loci available in public GenBank. Basic statistics showed that the average observed heterozygosity （Ho） amongst populations ranged from 0.5789 to 0.6824. However, a remarkable presence of inbreeding and heterozygote deficiencies were observed. To analyze population structure, pairwise FST coefficients explained only -10.3% variability from the subdivision of mitten crab populations, the remaining variability stems from the subdivision within subpopulations. Although the four populations had slight differentiation, different allelic frequencies resulted in distinct population structures. Two stocks and one farming population were clustered together to the phylogenetic branch of Yangtze crab, with an approximate membership of 95%. Whereas, another farming population was clustered singly to the phylogenetic branch of the Liaohe crab, with a membership of 97.1%. The tests for individual admixture showed that Yangtze crab had probably been contaminated with individuals from other water systems. Genetic relationships between populations also supported the conclusion that Yangtze crab and Liaohe crab had different gene pools in spite of the origins of the same species.展开更多
To understand the factors causing frequent outbreaks of harmful algae blooms in the Taihu Lake, China, we studied water quality and nutrient budget in Chinese mitten crab (Eriocheir sinensis) farm ponds in the eastern...To understand the factors causing frequent outbreaks of harmful algae blooms in the Taihu Lake, China, we studied water quality and nutrient budget in Chinese mitten crab (Eriocheir sinensis) farm ponds in the eastern part of the lake from November 2007 to December 2009. We estimated the nitrogen (N), phosphorus (P), and chemical oxygen demand (COD) loads. Materials input and output ponds, water exchange, and applied management practices of 838.5-hm2 crab ponds were surveyed using questionnaires. Water quality of 12 ponds, which were located no more than 2 km from East Taihu Lake, were monitored. The results show that water quality in the crab ponds was better than reference data. Feeds, including corn seed, commercial feed, trash fish, and gastropod, were the major sources of N and P input in the crab ponds, contributing 88.7% and 94.9%, respectively. In total, 60.5% of N and 37.3% of P were sequestered by macrophytes, and only 15.7% and 8.5% of them were discharged as effluent. The net loads of N and P in effluent were 16.43 kg/hm2/cycle and 2.16 kg/hm2/cycle, respectively, while the COD load was -17.88 kg/hm2/cycle. This indicated that crab farming caused minor negative impact on the trophic status of the lake area, which was attenuated by macrophytes. However, wastewater purification is still necessary in crab faming.展开更多
Identifying the geographic origins of Chinese mitten crabs is important for food safety and fair market competition.In this study,we used strontium(Sr) isotopes as a tool to trace the geographic origins of Chinese mit...Identifying the geographic origins of Chinese mitten crabs is important for food safety and fair market competition.In this study,we used strontium(Sr) isotopes as a tool to trace the geographic origins of Chinese mitten crabs.Chinese mitten crabs,water,and different types of crab feed were collected from four different lakes for Sr isotope analyses.The results showed that the Sr isotope compositions of the different parts from one single crab were consistent within error,indicating that any piece of a crab could be used to represent the Sr isotope characteristics of the whole crab.The Sr isotope compositions of Chinese mitten crabs from the same lake were consistent within the analytical error,and the values were similar to the Sr isotope composition of the water from the same lake.However,the Sr isotope compositions of water and crabs from different lakes are significantly different.Therefore,the Sr isotope compositions of Chinese mitten crabs are mainly controlled by lake water composition,while the impact of feed is limited.This study provides an effective method for tracing the geographic origins of Chinese mitten crabs.展开更多
Chinese mitten crab （Eriocheir sinensis） is an indigenous and ecologically and economically important species in the Liao River area, but its identification and genetic diversity remain poorly understood. To evaluat...Chinese mitten crab （Eriocheir sinensis） is an indigenous and ecologically and economically important species in the Liao River area, but its identification and genetic diversity remain poorly understood. To evaluate the germplasm resources of this species, samples were collected from these locations： four sub-populations from the Liao River area and one population from the Yangtze River area; one primer was used to distinguish between the Liao River and the Yangtze River crabs. Thirteen loci were used for crab genetic diversity analysis, and basic statistics showed that the collecting samples were purebred in the Liao River area. The average observed heterozygosity （H0） of the Liao River population was 0.5931, and the expected heterozygosity （He） was 0.8064. The polymorphism information content （PIC） was 0.7753, which showed that the Liao River population had high genetic diversity. The genetic differentiation index （FST） averaged 0.0342, meaning a low degree of differentiation; cluster analysis indicated that Hujia （HJ）, Xinli （XL） and Chenjia （CJ） sub-populations were allocated to the same cluster, while Baqiangzi （BQZ） sub-population was isolated. In summary, these data demonstrated that the crabs in the Liao River had high genetic diversity, but low genetic differentiation. Thus, the Liao River population had the potential for breeding selection. Furthermore, this study also provided valuable genetic information for the conservation of Chinese mitten crab.展开更多
The tropomyosin(TM)fractions of crab protems may cause allergic reactions in mdividuals susceptible to allergies;however,efficient and safe methods by which to reduce such allergenicity are not currently available.The...The tropomyosin(TM)fractions of crab protems may cause allergic reactions in mdividuals susceptible to allergies;however,efficient and safe methods by which to reduce such allergenicity are not currently available.Therefore,in this study,the effects of three different processing methods,i.e.,microwave,ultrasound,and high temperature-pressure(HTP)treatments,on the digestion stability of TM from Chinese mitten crab muscle and the allergenicity of TM digestion products were explored.sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis showed that microwaving had little effect on the digestion stability of TM.In contrast,ultrasound and HTP treatments facilitated the degradation of TM.Similarly,Western blotting and inhibition ELISA indicated that the IgE-binding activity of TM was significantly reduced after treatment with ultrasound or HTP.Among the three different proces sing methods,HTP was the most effective method for improving digestibility of TM and reducing immunoreactivity.This finding provides new insights into treatments for crab allergies.展开更多
Next to excessive nutrient loading,intensive aquaculture is one of the major anthropogenic impacts threatening lake ecosystems.In China,particularly in the shallow lakes of mid-lower Changjiang(Yangtze) River,continuo...Next to excessive nutrient loading,intensive aquaculture is one of the major anthropogenic impacts threatening lake ecosystems.In China,particularly in the shallow lakes of mid-lower Changjiang(Yangtze) River,continuous overstocking of the Chinese mitten crab(Eriocheir sinensis) could deteriorate water quality and exhaust natural resources.A series of crab yield models and a general optimum-stocking rate model have been established,which seek to benefit both crab culture and the environment.In this research,independent investigations were carried out to evaluate the crab yield models and modify the optimum-stocking model.Low percentage errors(average 47%,median 36%) between observed and calculated crab yields were obtained.Specific values were defined for adult crab body mass(135 g/ind.) and recapture rate(18%and 30%in lakes with submerged macrophyte biomass above and below 1 000 g/m^2)to modify the optimum-stocking model.Analysis based on the modified optimum-stocking model indicated that the actual stocking rates in most lakes were much higher than the calculated optimum-stocking rates.This implies that,for most lakes,the current stocking rates should be greatly reduced to maintain healthy lake ecosystems.展开更多
The genetic differences of 15 mitten crab populations from 6 river systems in China's Mainland and 1 population from Russia were studied based on RFLP analysis of mitochondrial cytochrome oxidase subunit I （CO I...The genetic differences of 15 mitten crab populations from 6 river systems in China's Mainland and 1 population from Russia were studied based on RFLP analysis of mitochondrial cytochrome oxidase subunit I （CO I）. The results showed that Tas I-RFLP pattern could be used as a genetic marker to distinguish Eriocheir hepuensis from Eriocheir sinensis, Eriocheirjaponica and Eriocheir leptognathus; genetic distances among 13 populations of Eriocheir sinensis range from 0 to 0.015, indicating that they were different geographic strains; the subspecies status of Eriocheir sinensis and Eriocheir hepuensis （population from Nanliujiang） were considered owning to their genetic distances of 0.02-0.044, indicating that genetic divergence between them was low; Eriocheir leptognathus （population from Nanpaihe, Tianjin） was the most distant taxon with genetic distances value of 0.147-0.195, which could be defined as genetic distances between species in genus Eriocheir.展开更多
To reveal the evolutionary relationship of three mitten crabs(Eriocheir sinensis,E.hepuensis,and E.japonica),complete mitogenomes and nuclear 5S rDNA sequences were analyzed.Sequencing revealed that the mitogenomes an...To reveal the evolutionary relationship of three mitten crabs(Eriocheir sinensis,E.hepuensis,and E.japonica),complete mitogenomes and nuclear 5S rDNA sequences were analyzed.Sequencing revealed that the mitogenomes analyzed shared conserved organization of the coding and non-coding regions but genetic variation was identified.Among the three mitten crabs distinct tandem repeats were identified in the mitochondrial D-loop region.The 5S gene(5S rDNA)sequence was highly conserved across the three species,whereas non-transcribed spacer(NTS)region exhibit high levels of variation including insertions,deletions and point mutations.Cluster analysis suggested that the three mitten crabs had their own independent 5S rDNA sequence variation and evolutionary pattern.Both mitogenome and 5S rDNA sequence analysis revealed significant genetic variation across the mitten crabs species.Phylogenetic analysis using mitogenome and 5S rDNA sequences demonstrated that E.japonica was relatively more distant from E.sinensis and E.hepuensis.This study extended our previous knowledge and confirmed that the three mitten crabs are likely to be genetically differentiated species.In addition,our study also provided insights into the conservation of pure natural resources of E.sinensis,an important aquaculture species.展开更多
文摘Chinese mitten crab （Eriocheir sinensis） has higher commercial value as food source than any other species of Eriocheir in China. To evaluate the germplasm resources and characterize the genetic diversity and population structure of the crabs in different water systems, two stocks and two farming populations were assessed with 25 polymorphic microsallite loci available in public GenBank. Basic statistics showed that the average observed heterozygosity （Ho） amongst populations ranged from 0.5789 to 0.6824. However, a remarkable presence of inbreeding and heterozygote deficiencies were observed. To analyze population structure, pairwise FST coefficients explained only -10.3% variability from the subdivision of mitten crab populations, the remaining variability stems from the subdivision within subpopulations. Although the four populations had slight differentiation, different allelic frequencies resulted in distinct population structures. Two stocks and one farming population were clustered together to the phylogenetic branch of Yangtze crab, with an approximate membership of 95%. Whereas, another farming population was clustered singly to the phylogenetic branch of the Liaohe crab, with a membership of 97.1%. The tests for individual admixture showed that Yangtze crab had probably been contaminated with individuals from other water systems. Genetic relationships between populations also supported the conclusion that Yangtze crab and Liaohe crab had different gene pools in spite of the origins of the same species.
基金Supported by the Major Projects on Control and Rectification of Water Body Pollution (No. 2008ZX07101-012)the Knowledge Innovation Program of the Chinese Academy of Sciences (No. KZCX1-YW14)+1 种基金the Aquaculture "three projects" of Jiangsu (No. J2009-12)the Agricultural Basic Research Fund of Suzhou (No. YJG0912)
文摘To understand the factors causing frequent outbreaks of harmful algae blooms in the Taihu Lake, China, we studied water quality and nutrient budget in Chinese mitten crab (Eriocheir sinensis) farm ponds in the eastern part of the lake from November 2007 to December 2009. We estimated the nitrogen (N), phosphorus (P), and chemical oxygen demand (COD) loads. Materials input and output ponds, water exchange, and applied management practices of 838.5-hm2 crab ponds were surveyed using questionnaires. Water quality of 12 ponds, which were located no more than 2 km from East Taihu Lake, were monitored. The results show that water quality in the crab ponds was better than reference data. Feeds, including corn seed, commercial feed, trash fish, and gastropod, were the major sources of N and P input in the crab ponds, contributing 88.7% and 94.9%, respectively. In total, 60.5% of N and 37.3% of P were sequestered by macrophytes, and only 15.7% and 8.5% of them were discharged as effluent. The net loads of N and P in effluent were 16.43 kg/hm2/cycle and 2.16 kg/hm2/cycle, respectively, while the COD load was -17.88 kg/hm2/cycle. This indicated that crab farming caused minor negative impact on the trophic status of the lake area, which was attenuated by macrophytes. However, wastewater purification is still necessary in crab faming.
基金financially supported by the National Key Research and Development Program of Chinathe project of Source Identification and Contamination Characteristics of Heavy Metals in Agricultural Land and Products (2016YFD0800300)by Natural Science Foundation of China (41721002)
文摘Identifying the geographic origins of Chinese mitten crabs is important for food safety and fair market competition.In this study,we used strontium(Sr) isotopes as a tool to trace the geographic origins of Chinese mitten crabs.Chinese mitten crabs,water,and different types of crab feed were collected from four different lakes for Sr isotope analyses.The results showed that the Sr isotope compositions of the different parts from one single crab were consistent within error,indicating that any piece of a crab could be used to represent the Sr isotope characteristics of the whole crab.The Sr isotope compositions of Chinese mitten crabs from the same lake were consistent within the analytical error,and the values were similar to the Sr isotope composition of the water from the same lake.However,the Sr isotope compositions of water and crabs from different lakes are significantly different.Therefore,the Sr isotope compositions of Chinese mitten crabs are mainly controlled by lake water composition,while the impact of feed is limited.This study provides an effective method for tracing the geographic origins of Chinese mitten crabs.
基金Supported by Open Project Program of Key Laboratory of Freshwater Aquatic Biotechnology and Breeding,Ministry of Agriculture,Heilongjiang Fisheries Research Institute,Chinese Academy of Fishery Sciences(FBB2016-01)
文摘Chinese mitten crab （Eriocheir sinensis） is an indigenous and ecologically and economically important species in the Liao River area, but its identification and genetic diversity remain poorly understood. To evaluate the germplasm resources of this species, samples were collected from these locations： four sub-populations from the Liao River area and one population from the Yangtze River area; one primer was used to distinguish between the Liao River and the Yangtze River crabs. Thirteen loci were used for crab genetic diversity analysis, and basic statistics showed that the collecting samples were purebred in the Liao River area. The average observed heterozygosity （H0） of the Liao River population was 0.5931, and the expected heterozygosity （He） was 0.8064. The polymorphism information content （PIC） was 0.7753, which showed that the Liao River population had high genetic diversity. The genetic differentiation index （FST） averaged 0.0342, meaning a low degree of differentiation; cluster analysis indicated that Hujia （HJ）, Xinli （XL） and Chenjia （CJ） sub-populations were allocated to the same cluster, while Baqiangzi （BQZ） sub-population was isolated. In summary, these data demonstrated that the crabs in the Liao River had high genetic diversity, but low genetic differentiation. Thus, the Liao River population had the potential for breeding selection. Furthermore, this study also provided valuable genetic information for the conservation of Chinese mitten crab.
基金supported by the earmarked fund for the Anhui Provincial Modern Agri-industry Technology Research System(AHCYJSTX-08)the China Agriculture Research System of MOF and MARA(CARS-48)。
文摘The tropomyosin(TM)fractions of crab protems may cause allergic reactions in mdividuals susceptible to allergies;however,efficient and safe methods by which to reduce such allergenicity are not currently available.Therefore,in this study,the effects of three different processing methods,i.e.,microwave,ultrasound,and high temperature-pressure(HTP)treatments,on the digestion stability of TM from Chinese mitten crab muscle and the allergenicity of TM digestion products were explored.sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis showed that microwaving had little effect on the digestion stability of TM.In contrast,ultrasound and HTP treatments facilitated the degradation of TM.Similarly,Western blotting and inhibition ELISA indicated that the IgE-binding activity of TM was significantly reduced after treatment with ultrasound or HTP.Among the three different proces sing methods,HTP was the most effective method for improving digestibility of TM and reducing immunoreactivity.This finding provides new insights into treatments for crab allergies.
基金Supported by the State Key Laboratory of Freshwater Ecology and Biotechnology(Nos.2014FB14,2011FBZ14)the Hubei Province(No.2001AA201A05)+2 种基金the National Basic Research Program of China(973Program)(No.2008CB418006)the Chinese Academy of Sciences(No.KZCX1-SW-12)supported by the Youth Innovation Association of Chinese Academy of Sciences(No.2014312)
文摘Next to excessive nutrient loading,intensive aquaculture is one of the major anthropogenic impacts threatening lake ecosystems.In China,particularly in the shallow lakes of mid-lower Changjiang(Yangtze) River,continuous overstocking of the Chinese mitten crab(Eriocheir sinensis) could deteriorate water quality and exhaust natural resources.A series of crab yield models and a general optimum-stocking rate model have been established,which seek to benefit both crab culture and the environment.In this research,independent investigations were carried out to evaluate the crab yield models and modify the optimum-stocking model.Low percentage errors(average 47%,median 36%) between observed and calculated crab yields were obtained.Specific values were defined for adult crab body mass(135 g/ind.) and recapture rate(18%and 30%in lakes with submerged macrophyte biomass above and below 1 000 g/m^2)to modify the optimum-stocking model.Analysis based on the modified optimum-stocking model indicated that the actual stocking rates in most lakes were much higher than the calculated optimum-stocking rates.This implies that,for most lakes,the current stocking rates should be greatly reduced to maintain healthy lake ecosystems.
基金Tianjin Development Foundation of Science and Technology and International Cooperation Foundation(033803511,033803511G)Tianjin Higher Educational Development Foundation(2004BA31)
文摘The genetic differences of 15 mitten crab populations from 6 river systems in China's Mainland and 1 population from Russia were studied based on RFLP analysis of mitochondrial cytochrome oxidase subunit I （CO I）. The results showed that Tas I-RFLP pattern could be used as a genetic marker to distinguish Eriocheir hepuensis from Eriocheir sinensis, Eriocheirjaponica and Eriocheir leptognathus; genetic distances among 13 populations of Eriocheir sinensis range from 0 to 0.015, indicating that they were different geographic strains; the subspecies status of Eriocheir sinensis and Eriocheir hepuensis （population from Nanliujiang） were considered owning to their genetic distances of 0.02-0.044, indicating that genetic divergence between them was low; Eriocheir leptognathus （population from Nanpaihe, Tianjin） was the most distant taxon with genetic distances value of 0.147-0.195, which could be defined as genetic distances between species in genus Eriocheir.
基金The authors would like to thank to Mr.Yongju Luo at Guangxi Fisheries Institute in China for sampling the Hepu mitten crab.This work was funded by the Shanghai Agriculture Applied Technology Development Program,China(Grant No.G2017-02-08-00-10-F00076)the Shanghai Mitten Crab Industry Technology System Project(Grant No.2017e2021)+2 种基金Young teachers training Project of Shanghai Municipal Education Commission(A1-2056-16-0026)the Shanghai Science and Technology Project(Grant No.16391905300,13DZ2251800)Doctoral Program of Shanghai Ocean University(A2-0203-00-100315).
文摘To reveal the evolutionary relationship of three mitten crabs(Eriocheir sinensis,E.hepuensis,and E.japonica),complete mitogenomes and nuclear 5S rDNA sequences were analyzed.Sequencing revealed that the mitogenomes analyzed shared conserved organization of the coding and non-coding regions but genetic variation was identified.Among the three mitten crabs distinct tandem repeats were identified in the mitochondrial D-loop region.The 5S gene(5S rDNA)sequence was highly conserved across the three species,whereas non-transcribed spacer(NTS)region exhibit high levels of variation including insertions,deletions and point mutations.Cluster analysis suggested that the three mitten crabs had their own independent 5S rDNA sequence variation and evolutionary pattern.Both mitogenome and 5S rDNA sequence analysis revealed significant genetic variation across the mitten crabs species.Phylogenetic analysis using mitogenome and 5S rDNA sequences demonstrated that E.japonica was relatively more distant from E.sinensis and E.hepuensis.This study extended our previous knowledge and confirmed that the three mitten crabs are likely to be genetically differentiated species.In addition,our study also provided insights into the conservation of pure natural resources of E.sinensis,an important aquaculture species.
