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1.
Large areas of hypoxic water have recently been reported in the East China Sea. It is hypothesized that hypoxia may be partially responsible for the decline of some fish stocks. We evaluated the effect of hypoxia on large yellow croaker (Pseudosciaena crocea). The fish were exposed to three concentrations of dissolved oxygen (DO; 1.5 mg/L and 2.0 mg/L, and 6.5 mg/L control). We collected blood after 6, 12, 24, 48, and 96 h exposure. There was a significant increase in red blood count, hematocrit, hemoglobin concentration, and mean corpuscular hemoglobin in the group exposed to 1.5 mg/L DO after 6 h or 12 h, and a delayed increase (only elevated after 48 h and 96 h) in these indices in the group exposed to 2.0 mg/L DO. Plasma glucose concentrations increased significantly in both hypoxic groups after 24 h. Furthermore, plasma lactate and lactate dehydrogenase activity increased significantly after the first 6 h exposure in both hypoxic groups. Our results suggest that large yellow croakers could not maintain the aerobic pathway and instead use anaerobic metabolism for survival when DO levels fall below 2.0 mg/L. We conclude that the occurrence of hypoxia (<2 mg/L DO) in the East China Sea could cause metabolic stress for large yellow croakers and may be partially responsible for the population decline of this species. 相似文献
2.
Effects of hypoxia on dopamine concentration and the immune response of White Shrimp (Litopenaeus vannamei) 总被引：1，自引：0，他引：1
Effects of hypoxia on the dopamine concentration and the immune response of White Shrimp Litopenaeus vannamei were studied. The results showed that hypoxia had significant effects on the concentration of dopamine (DA) in the haemolymph,
haemocyte count, phenoloxidase activity, phagocytic activity of haemocytes and bacteriolytic and antibacterial activity in
the haemolymph (P<0.05). The concentration of the dopamine in haemolymph reached its maximum in the 3.0 and 1.5 mg L−1 DO groups at 12 h and 6 h, and then returned to normal after 24 h and 12 h, respectively. All immune parameters decreased
with the reduction of dissolved oxygen. Total haemocyte count (THC), the hyaline cells and semi-granular cells in the 3.0
mg L−1 DO group became stable after 12 h, while granular cells did so after 24 h. The THC and different haemocyte count (DHC) in
the 1.5 mg L−1 DO group became stable after 24 h. Phenoloxidase activity and bacteriolytic activity in the 3.0 and 1.5 mg L−1 DO groups reached their stable levels after 24 h and 12 h respectively, while phagocytic activity and antibacterial activity
became stable after 24 and 12, and 36 and 24 h, respectively. It was also indicated that the changes of dopamine concentrations
in haemolymph, haemocyte count and phenoloxidase activity were obviously related to the exposure time under hypoxic conditions. 相似文献
3.
Effects of hypoxia on the dopamine concentration and the immune response of White Shrimp Litopenaeus vannamei were studied. The results showed that hypoxia had significant effects on the concentration of dopamine (DA) in the haemolymph, haemocyte count, phenoloxidase activity, phagocytic activity of haemocytes and bacteriolytic and antibacterial activity in the haemolvmph (P<0.05). The concentration of the dopamine in haemolymph reached its maximum in the 3.0 and 1.5mgL-1 DO groups at 12h and 6h, and then returned to normal after 24h and 12h, respectively. All immune parameters decreased with the reduction of dissolved oxygen. Total haemocyte count (THC), the hyaline cells and semi-granular cells in the 3.0mgL-1 DO group became stable after 12h,while granular cells did so after 24h, The THC and different haemocyte count (DHC) in the 1.5mgL-1 DO group became stable alter 24h. Phenoloxidase activity and bacteriolytic activity in the 3.0 and 1.5mgL-1 DO groups reached their stable levels after 24 h and 12 h respectively, while phagocytic activity and antibacterial activity became stable after 24 and 12, and 36 and 24 It, respec-tively. It was also indicated that the changes of dopamine concentrations in haemolymph, haemocyte count and phenoloxidase activ-ity were obviously related to the exposure time under hypoxic conditions. 相似文献
4.
5.
The bottom aquaculture of yesso scallop(Pa tinopecten yessoensis)has developed rapidly in the north of Yellow Sea,China,but not without accompanying productivity problems.We,therefore,conducted field surveys to investigate factors related to growth and mortality rates of bottom-cultured scallops after release.Specifically,we focused on the effects of total antioxidant capacity(TAOC)and three key enzymes involved in antioxidant and metabolic function:glutamic pyruvic transaminase(GPT),lactic dehydrogenase(LDH),and superoxide dismutase(SOD).Across summer and winter,we also measured the relative mRNA expression of GPT and SOD to understand their seasonal variation in the scallops,along with how such variation correlated to growth and mortality.Results show that bottom cultured scallops experienced mass mortality during the first six months post-release.During winter(December),scallops grew more rapidly and suffered less mortality than in summer(August).The observed lower performance probably resulted from less advantageous environmental factors during the summer seasons,such as high temperature and low dissolved oxygen.These environmental stressors enhance protein consumption while decreasing energetic resources in scallops.Furthermore,scallops in summer exhibited high antioxidant levels that probably competed for energy with process integral to growth and survival.These negative factors combined to elevate mortality rates.In conclusion,we provided evidence suggesting correlations between metabolic/antioxidant activity and growth and mortality of bottom-cultured yesso scallops.These correlations implied us an accurate method to estimate the performance of bottom culture system.Suggestions about innovative aquaculture techniques were also discussed in the study.Our results might provide a possible guideline to the improvement of bottom culture techniques for this commercially valuable seafood species. 相似文献
6.
Survival, growth and immune response of the scallop, Chlamys farreri, cultured in lantern nets at five different depths (2, 5, 10, 15, and 20 m below the sea surface) were studied in Haizhou
Bay during the hot season (summer and autumn) of 2007. Survival and growth rates were quantified bimonthly. Immune activities
in hemolymph (superoxide dismutase (SOD) and acid phosphatase (ACP)) were measured to evaluate the health of scallops at the
end of the study. Environmental parameters at the five depths were also monitored during the experiment. Mortalities mainly
occurred during summer. Survival of scallops suspended at 15 m (78.0%) and 20 m (86.7%) was significantly higher than at 2
m (62.9%), 5 m (60.8%) or 10 m (66.8%) at the end of the study. Mean shell height grew significantly faster at 10 m (205.0
μm/d) and 20 m (236.9 μm/d) than at 2, 5 or 15 m in summer (July 9 to September 1); however, shell growth rate at 20 m was
significantly lower than at the other four depths in autumn (September 2 to November 6). In contrast to summer, scallops at
5 m grew faster (262.9 μm/d) during autumn. The growth of soft tissue at different depths showed a similar trend to the shell.
Growth rates of shell height and soft tissue were faster in autumn than in summer, with the exception of shell height at 20
m. SOD activity of scallops increased with depth, and ACP activity was significantly higher at 15 and 20 m than at other depths,
which suggests that scallops were healthier near the bottom. Factors explaining the depth-related mortality and growth of
scallops are also discussed. We conclude that the mass mortality of scallop, C. farreri, during summer can be prevented by moving the culture area to deeper water and yield can be maximized by suspending the scallops
in deep water during summer and then transferring them to shallow water in autumn. 相似文献
7.
【目的】研究波纹龙虾(Panulirus homarus)胚胎对生态因子的耐受能力,为龙虾繁殖提供数据。【方法】采用封闭静水实验方法和常规生物急性毒性实验法。在温度(30±0.5)℃,盐度30,pH(8.10±0.1)和溶解氧(DO)为(5.0±0.5)mg/L条件下,分别进行温度、盐度、pH的骤变和渐变对波纹龙虾胚胎存活影响研究;根据急性毒性预实验结果设置等对数间距浓度值,进行氨氮和亚硝酸盐氮对波纹龙虾胚胎的急性毒性实验。【结果与结论】波纹龙虾胚胎发育的温度、盐度和pH耐受范围分别为7~36℃、15~45和5.8~9.4;波纹龙虾胚胎适宜温度为15~30℃,适宜盐度为30~35,适宜pH为7.0~8.5;氨氮和亚硝酸盐氮毒性效应与浓度和暴露时间呈正相关。氨氮和亚硝酸盐氮暴露24~96 h,波纹龙虾胚胎存活率组间存在显著性差异(P<0.05)。氨氮对波纹龙虾胚胎24、48、72和96 h的半致死浓度(LC50)分别是180.46、61.11、41.87、26.58 mg/L,安全浓度(SC)为2.66 mg/L;亚硝酸盐氮对波纹龙虾胚胎24、48、72和96 h的LC50分别是839.50、423.75、214.48、135.41 mg/L,SC为13.54 mg/L。 相似文献
8.
《中国海洋湖沼学报》2017,(3)
To assess the effects of hypoxia, macrobenthic communities along an estuarine gradient of the Changjiang estuary and adjacent continental shelf were analyzed. This revealed spatial variations in the communities and relationships with environmental variables during periods of reduced dissolved oxygen(DO) concentration in summer. Statistical analyses revealed significant differences in macrobenthic community composition among the three zones: estuarine zone(EZ), mildly hypoxic zone(MHZ) in the continental shelf, and normoxic zone(NZ) in the continental shelf(Global R =0.206, P =0.002). Pairwise tests showed that the macrobenthic community composition of the EZ was significantly different from the MHZ(pairwise test R =0.305, P =0.001) and the NZ(pairwise test R =0.259, P =0.001). There was no significant difference in macrobenthic communities between the MHZ and the NZ(pairwise test R =0.062, P =0.114). The taxa included small and typically opportunistic polychaetes, which made the greatest contribution to the dissimilarity between the zones. The effects of mild hypoxia on the macrobenthic communities are a result not only of reduced DO concentration but also of differences in environmental variables such as temperature, salinity, and nutrient concentrations caused by stratification. 相似文献
9.
The effects of 60-day starvation on survival rate. condition index (CI) , changes ofnutrient composition of different tissues, respiration and excretion of scallop ChlartnCs farreri were studiedin laboratory from Oct. 17 to Dec. 15 ,1997. Two groups (control and starvation with 200 individualseach) were cultured in two 2 m3 tanks, with 31 to 32 salinity water at 1 7 “C . Starvation effects were mea-sured alter 1 0, 20, 40 and 60 days. There was no mass mortality of scallops cf the two tanks and survivalrates of the control and starvation groups were 93 .5 % and 92.0 %, respectively. Starvation had strongeffect on the meat condition of the scallops, especially after 10 days; when relative lipid percentagedropped sharply while relative protein percentage increased. The impact of starvation on the oxygen consumption mtc (OCR) and the ammonia-N cxcretion mtc (AER) was obvious. 相似文献
10.
Microsatellite markers have become one kind of the most important molecular tools used in various researches. A large number of microsatellite markers are required for the whole genome survey in the fields of molecular ecology, quantitative genetics and genomics. Therefore, it is extremely necessary to select several versatile, low-cost, efficient and time- and labor-saving methods to develop a large panel of microsatellite markers. In this study, we used Zhikong scallop (Chlamys farreri) as the target species to compare the efficiency of the five methods derived from three strategies for microsatellite marker development. The results showed that the strategy of constructing small insert genomic DNA library resulted in poor efficiency, while the microsatellite-enriched strategy highly improved the isolation efficiency. Although the mining public database strategy is time- and cost-saving, it is difficult to obtain a large number of microsatellite markers, mainly due to the limited sequence data of non-model species deposited in public databases. Based on the results in this study, we recommend two methods, microsatellite-enriched library construction method and FIASCO-colony hybridization method, for large-scale microsatellite marker development. Both methods were derived from the mi-crosatellite-enriched strategy. The experimental results obtained from Zhikong scallop also provide the reference for microsatellite marker development in other species with large genomes. 相似文献
11.
4种对虾耗氧率、CO_2排出量、呼吸商和窒息点的研究（英文） 总被引：1，自引：0，他引：1
蒋静南 《广东海洋大学学报》1999,(1)
较系统研究了斑节对虾、墨吉对虾、日本对虾和刀额新对虾等４种对虾的耗氧率、ＣＯ２排出量、呼吸商和窒息点。结果表明，同一种类不同大小和不同种类及生活习性不同，耗氧率、ＣＯ２排出量、呼吸商和窒息点有较大的差别。日本对虾、刀额新对虾的耗氧率、ＣＯ２排出量比其他两种虾低。墨吉对虾次之，斑节对虾为最高。对ＤＯ忍受能力，刀额新对虾最强，在ＤＯ０．６０ｍｇ／Ｌ才开始出现窒息。斑节对虾次之，在ＤＯ降至０．８８ｍｇ／Ｌ出现窒息。墨吉对虾在ＤＯ１．１９ｍｇ／Ｌ出现窒息。日本对虾忍受ＤＯ能力最差，在以ＤＯ１．３１ｍｇ／Ｌ出现窒息。 相似文献
12.
The experimental results showed that: 1) The embryonic development of bay scallop is inhibited at a dissolved oxygen range
of 1.38–3.64×10−3 at 23°C, and completely blocked below the lower limit. 2) The tolerance of larvae to anoxia increased with larval sizes and
was related to their oxygen debt. 3) The scallop larvae exhibited specific behavioral responses to oxygen deficiency, which
finally led to velum disintegration and larval death. The possible relationship between environmental oxygen deficiency and
the disease of disintegration of the larval velum is also discussed. In this study, considerable oxygen debt was found in
bay scallop larvae, which was greater in small animals. Based on the works of previous authors, a new concept is proposed
for the estimation of oxygen debt, namely, the compensatory rate of oxygen debt (CROD). This can be used in intra—or interspecific
comparison of oxygen debt. The results can be helpful in the management of water quality and for the prevention of larval
diseases encountered in scallop culture.
Contribution No. 2167 from the Institute of Oceanology, Chinese Academy of Sciences. 相似文献
13.
The large water-pumping and particle-capturing gills of the filter-feeding blue mussel Mytilus edulis are oversized for respiratory purposes. Consequently, the oxygen uptake rate of the mussel has been suggested to be rather insensitive to decreasing oxygen concentrations in the ambient water, since the diff usion rate of oxygen from water flowing through the mussel determines oxygen uptake. We tested this hypothesis by measuring the oxygen uptake in mussels exposed to various oxygen concentrations. These concentrations were established via N2-bubbling of the water in a respiration chamber with mussels fed algal cells to stimulate fully opening of the valves. It was found that mussels exposed to oxygen concentrations decreasing from 9 to 2 mg O_2/L resulted in a slow but significant reduction in the respiration rate, while the filtration rate remained high and constant. Thus, a decrease of oxygen concentration by 78% only resulted in a 25% decrease in respiration rate. However, at oxygen concentrations below 2 mg O_2/L M. edulis responded by gradually closing its valves, resulting in a rapid decrease of filtration rate, concurrent with a rapid reduction of respiration rate. These observations indicated that M.edulis is no longer able to maintain its normal aerobic metabolism at oxygen concentration below 2 mg O 2/L, and there seems to be an energy-saving mechanism in bivalve molluscs to strongly reduce their activity when exposed to low oxygen conditions. 相似文献
14.
Development of 101 novel EST-derived single nucleotide polymorphism markers for Zhikong scallop (Chlamys farreri) 总被引：1，自引：0，他引：1
Zhikong scallop(Chlamys farreri) is an important maricultured species in China.Many researches on this species,such as population genetics and QTL fine-mapping,need a large number of molecular markers.In this study,based on the expressed sequence tags(EST),a total of 300 putative single nucleotide polymorphisms(SNPs) were selected and validated using high resolution melting(HRM) technology with unlabeled probe.Of them,101(33.7%) were found to be polymorphic in 48 individuals from 4 populations.Further evaluation with 48 individuals from Qingdao population showed that all the polymorphic loci had two alleles with the minor allele frequency ranged from 0.046 to 0.500.The observed and expected heterozygosities ranged from 0.000 to 0.925 and from 0.089 to 0.505,respectively.Fifteen loci deviated significantly from Hardy-Weinberg equilibrium and significant linkage disequilibrate was detected in one pair of markers.BLASTx gave significant hits for 72 of the 101 polymorphic SNP-containing ESTs.Thirty four polymorphic SNP loci were predicted to be non-synonymous substitutions as they caused either the change of codons(33 SNPs) or pretermination of translation(1 SNP).The markers developed can be used for the population studies and genetic improvement on Zhikong scallop. 相似文献
15.
Severe hypoxia was observed in the submarine canyon to the east of the Changjiang estuary in July 14, 2015, two days after typhoon Chan-hom. The oxygen concentration reached as low as 2.0 mg/L and occupied a water column of about 25 m. A ROMS model was configured to explore the underlying physical processes causing the formation of hypoxia. Chan-hom passed through the Changjiang estuary during the neap tide. The stratification was completely destroyed in the shallow nearshore region when typhoon passing. However, it was maintained in the deep canyon, though the surface mixed layer was largely deepened. The residual water in the deep canyon is considered to be the possible source of the later hypoxia. After Chan-hom departure, not only the low salinity plume water spread further off shore, but also the sea surface temperature (SST) rewarmed quickly. Both changes helped strengthen the stratification and facilitate the formation of hypoxia. It was found that the surface heat flux, especially the solar short wave radiation dominated the surface re-warming, the off shore advection of the warmer Changjiang Diluted Water (CDW) also played a role. In addition to the residual water in the deep canyon, the Taiwan Warm Current (TWC) was found to flow into the deep canyon pre- and soon post- Chan-hom, which was considered to be the original source of the hypoxia water.
相似文献16.
Two Large-insert genomic bacterial artificial chromosome （BAC） libraries of Zhikong scallop Chlamys farreri were constructed to promote our genetic and genomic research. High-quality megabase-sized DNA was isolated from the adductor muscle of the scallop and partially digested by BamH I and Mbo I, respectively. The BamH I library consisted of 53 760 clones while the Mbo I library consisted of 7 680clones. Approximately 96 % of the clones in BamH I library contained nuclear DNA inserts in average size of 100 kb, providing a coverage of 5.3 haploid genome equivalents. Similarly, the Mbo I library with an average insert of 145 kb and no insert-empty clones, thus providing a genome coverage of 1.1 haploid genome equivalents. 相似文献
17.
Pei Hong Shihao Gong Chunbo Wang Yilin Shu Xingqiang Wu Cuicui Tian Oscar Omondi Donde Pei Cai Huaming Wu Bangding Xiao 《中国海洋湖沼学报》2020,38(3):733-744
At present, the understanding of the dynamics of denitrifiers at different dissolved oxygen (DO) layers under organic carbon consumption within the surface sediments remains inadequate. In this study, high-throughput sequencing and quantitative PCR targeting nirS gene were used to analyze the denitrifier abundance dynamics, community composition, and structure for aerobic (DO 0.5–6.9 mg/L), hypoxic-anoxic (DO 0–0.5 mg/L), and anoxic (DO 0 mg/L) layers in surface sediments under organic carbon consumption. Based on the analysis of nirS gene abundance, the values of denitrifying bacteria decreased with organic carbon consumption at different DO layers. When the bacterial species abundance at the genus level were compared between the high-carbon and low-carbon sediments, there was significant increase in 6 out of 36, 7 out of 36 and 6 out of 36 genera respectively for the aerobic, hypoxic-anoxic and anoxic layers. On the other hand, 14 out of 36, 9 out of 36 and 15 out of 36 genera showed significant decrease in bacterial species abundance respectively for the aerobic, hypoxic-anoxic and anoxic layers. Additionally, 14 out of 36, 20 out of 36, and 15 out of 36 genera had no change in bacterial species abundance respectively for the aerobic, hypoxic-anoxic, and anoxic layers. This indicates that the carbon utilization ability of different denitrifiers on each DO layers was generally different from each other. Diversity of denitrifying bacteria also presented significant differences in different DO layers between the high- and low-carbon content sediment layers. Moreover, under the high-carbon and low-carbon content, the abundance of nirS gene showed a high peak within the hypoxic-anoxic regions, suggesting that this region might be the main distribution area for the denitrifying bacteria within the surface sediments. Furthermore, community of unique denitrifiers occurred in different DO layers and the adaptive changes of the denitrifier community followed the organic carbon consumption. 相似文献
18.
Chitosan oligosaccharide-Ca complex accelerates the depuration of cadmium from Chlamys ferrari 总被引：1，自引：0，他引：1
This study investigated the effect of a chitosan oligosaccharide-Ca complex (COS-Ca) on the depuration of cadmium (Cd) from Chlamys ferrari. After exposure to 0.5 mg L-1 CdCl2 for 3 or 7 d, the scallops were treated by COS-Ca prior to determina-tion of Cd, calcium (Ca) and zinc (Zn) contents, Cd distribution in organs, malondialdehyde (MDA) content and antioxidant variables. Results showed that COS-Ca reduced Cd content in the viscera of the scallops, with highest Cd depuration rate (47%) observed on day 3. The COS-Ca concentration substantially affected Cd depuration, and the exposure to 8.75 mg L-1 COS-Ca led to significantly higher Cd depuration rate compared with those of lower COS-Ca concentrations (1.75, 3.5, 5.25, and 7.00 mg L-1). Distribution analysis of Cd in scallop organs indicated that COS-Ca significantly reduced Cd content in the kidney throughout the 5-d experiment, as well as in the gill during the early stage of Cd depuration. In addition, COS-Ca treatment decreased glutathione peroxidase (GSH-Px) activity and MDA content while increasing superoxide dismutase (SOD) and catalase (CAT) activities on different days. Our work suggested COS-Ca complex treatment as an effective method for acceleration of Cd depuration from Cd-contaminated bivalves. 相似文献
19.
GUO Huihui BAO Zhenmin DU Huixia ZHANG Lingling WANG Shi SUN Luyang MOU Xiaoyu HU Xiaoli 《中国海洋大学学报(英文版)》2013,12(1):97-102
Cytochrome P450 (CYP) superfamily is one of the membership largest and function most diverse protein superfamily recogniozed among living beings. Members of this superfamily were further assigned to different families and subfamilies based on their amino acid similarities. According to their phylogenetic relationships, the CYP genes which likely diverged from common ancestor gene and may share common functions were grouped into one clan. Widely distributing scallops are a group of the most conspicuous bivalve; however the studies on their CYP is acarce. In this study, we searched the genome and expressed sequence tags of Zhikong scallop (Chlamys farreri) for CYP genes. In total, 88 non-redundant CYP were identified, which were homed in 13 CYPs gene families. Phylogenetic analysis divided these genes into 4 CYP clans. As in deuterostomes, Clan 2 was the largest, which contained 33 genes belonging to CYP1, CYP2, CYP17 and CYP356 families. Clan 3 contgained 19 genes belonging to CYP3, CYP5 and CYP30 families. Clan 4 contained 23 genes, all belonging to CYP4 family. The mitochondrial CYP clan contained 9 genes belonging to CYP10 and CYP24 families. In comparison, protostomes (C. farreri, D. pluex, D. melanogaster) contained more CYP genes than deuterostomes (S. purpuratus and vertebrates) in Clan 2 but less genes in Clan 3 and Clan 4. Our findings will aid to deciphering CYP function and evolution in scallops and bivalves. 相似文献
20.
ＩＮＴＲＯＤＵＣＴＩＯＮＳｅｄｉｍｅｎｔｏｘｙｇｅｎｄｅｍａｎｄ(ＳＯＤ)ｉｎｃｌｕｄｅｓｂｉｏｌｏｇｉｃａｌａｎｄｃｈｅｍｉｃａｌｏｘｙｇｅｎｄｅｍａｎｄ(ＧｅｏｒｇｅａｎｄＪｏｓｅｐｈ,1980),ｉｓａｎｉｍｐｏｒｔａｎｔｆａｃｔｏｒａｆｆｅｃｔｉｎｇｄｉｓｓｏｌｖｅｄｏｘｙｇｅｎ(ＤＯ)ａｎｄｈａｓｂｅｃｏｍｅａｎｉｍｐｏｒｔａｎｔｐａｒａｍｅｔｅｒｉｎｍａｎｙｗａｔｅｒｑｕａｌｉｔｙｍｏｄｅｌｓｆｏｒｃｕｌｔｕｒｅｐｏｎｄｓ(Ｍａｄｅｎｊｉａｎ,1990;Ｆａｎｇ,1991).Ｓｏｉｔｉｓｎｅｃｅｓｓａｒｙｔｏ… 相似文献