Research was conducted on topmouth culter (Culter alburnus) grown in ponds and lakes as well as wild types in order to determine their chemical composition and nutritional value. There are three types of fish that dif...Research was conducted on topmouth culter (Culter alburnus) grown in ponds and lakes as well as wild types in order to determine their chemical composition and nutritional value. There are three types of fish that differ in their proximate composition, amino acids, fatty acids, and minerals. Wild fish had a significantly lower crude lipid contents than cultured fish (P P ∑PUFAs) showed an obviously opposite trend. As compared with cultured fish, wild fish had significantly higher levels of n-3 PUFAs, arachidonic acid (AA), eicosapentaenoic acid (EPA) and docosahxaenoic acid (DHA) (P P > 0.05), except for Na, Fe and Se. In conclusion, diet composition and external aqueous environment may determine the differences between wild and cultured topmouth culter.展开更多
Geographic isolation is a key factor in shaping the genetic structure of many fish species.Two sympatric species,Culter alburnus and C.mongolicus,are economically important fish that are widely distributed in China an...Geographic isolation is a key factor in shaping the genetic structure of many fish species.Two sympatric species,Culter alburnus and C.mongolicus,are economically important fish that are widely distributed in China and have been recently used as new aquaculture species.We used the mitochondrial DNA control region(CR)as a marker to investigate the genetic structure of the two species.Phylogenetic analysis revealed two major lineages(Lineages I and II)that were highly consistent with geographical patterns for C.alburnus and C.mongolicus.Based on genetic distance,the Zhujiang(Pearl)River Basin(ZRB)populations potentially represented a cryptic subspecies,which might be differentiated as the result of strict geographic isolation,an earlier diverged event,or peripheral areas.Genetic diversity analysis suggested that the Changjiang(Yangtze)River Basin(CRB)populations are located at,or near the core region of their origination,not only due to the larger population size at the CRB,but also their habitat diversity and suitability for its survival,and the genetic diversity dif ferences among basin populations were significant for the two species.Moreover,demographic analysis indicated that the two Culter species and most populations had undergone a period of population expansion during warm interglacial periods.However,the C.alburnus population of Huaihe River Basin(Weishan Lake)exhibited different patterns during the interglacial period,which may due to the latest diverged time of HRB and Weishan Lake located at the permafrost.Notably,the ZRB(in Songtao Reservoir)C.mongolicus population showed no genetic diversity and had a unique haplotype,which could be treated as a special gene pool for species conservation.In summary,geographic isolation is most likely responsible for the two Culter species distribution patterns.展开更多
[ Objective ] This study aimed to provide references for reasonable drug administration in Culter mongolicus and promote the development of its breeding industry. [Method] C. mongolicus was administrated with cypermet...[ Objective ] This study aimed to provide references for reasonable drug administration in Culter mongolicus and promote the development of its breeding industry. [Method] C. mongolicus was administrated with cypermethrin, mebendazole, trichlorfon, cupric sulfate, trichloroisocyanuric acid, povidone iodine and phoxim, respectively, to analyze its susceptibility to different drugs. [ Result] C. mongolicus was very sensitive to cypermethrin; the median tolerance limit （TLM） at 3,8 h was 0. 072mg/L, minimum lethal concentration was 0. 063 - 0. 069 mg,/L, safe concentration was 0. 021 6 mg/L. C. mongolicus was insensitive to mebendazole, trichlorfon, cupric sulfate, trichloroisocyanuric acid and povidone iodine. According to safe concentration of various drugs, C. mongolicus exhibited higher susceptibility to cypermethrin than to phoxim. [ Conclusion] This study laid a solid foundation for better protection and development of C. mongolicus resources.展开更多
The relationship between body size and stable isotopic signatures of the omnivorous Redfin Culter(C ultrichthys erythropterus),commonly found in East Lake Taihu,was investigated. Previous analyses of C. erythropterus ...The relationship between body size and stable isotopic signatures of the omnivorous Redfin Culter(C ultrichthys erythropterus),commonly found in East Lake Taihu,was investigated. Previous analyses of C. erythropterus stomach contents have shown that this species undergoes a diet switch from being predominantly zooplanktivorous to piscivorous during its life history. This was confirmed by stable carbon isotopic signature(δ 13 C) in this study,in which δ 13 C was positively correlated with both standard length and weight. The importance of littoral-benthic resources in supporting C. erythropterus during its lifespan was also demonstrated using a two-source mixing model,the results of which showed a significant increasing trend in the contribution of littoral-benthic energy. However,the stable nitrogen isotopic signature(δ 15N) exhibited an unusual pattern compared with previous studies. The δ 15 N of C. erythropterus showed no relationship with body size,even though dietary changes were observed. This indicated that δ 15 N alone cannot fully reflect a diet shift in a species and possible variability in isotopic signatures over its life history. This should be considered when using stable isotopic signatures to investigate intra-specific variations and the timing of life-history events,such as estimating the trophic positions of fish species.展开更多
Many Ethiopian immigrants to Israel had their names changed to traditional Jewish names when arriving in Israel as children,as part of the melting pot conception.The purpose of the current study was to examine the per...Many Ethiopian immigrants to Israel had their names changed to traditional Jewish names when arriving in Israel as children,as part of the melting pot conception.The purpose of the current study was to examine the perception of Jewish-Israeli identity among Jews of Ethiopian descent with the reverse name change they performed in adulthood.For this study,144 respondents were sampled,of whom 120 had had their name changed when immigrating to Israel.Of those whose name was changed,100 later changed their name back to the original name given by their parents.The study utilized an attitude questionnaire that sought to explore three research hypotheses.The first hypothesis was that the Jewish Israeli identity of those whose name had not been changed was stronger than that of those whose name was changed.With regard to this hypothesis,significant differences were found in the Jewish identity of those whose name had been changed and those who had not,such that those whose name had been changed portrayed a weaker sense of Israeli identity than those who had not.The second hypothesis was that those who changed their name back had a stronger Jewish Israeli identity than those who did not.The findings indicate that those who changed their name back show a weaker Jewish Israeli identity than those who decided not to revert to their original name.The third hypothesis was that various personal variables have an effect on the perception of Jewish identity,in addition to the name change.The control variables were not found to be significant,i.e.,sex and age had no significant influence on Jewish Israeli identity.These findings reinforce the findings concerning the previous hypotheses and indicate that Jewish Israeli identity is considerably connected to the name change.The main research finding is that the name change has an effect on the Jewish Israeli identity of Jews of Ethiopian descent,and this is a double effect.The outcomes of the name change cause these people to feel that they were forced to erase their culture,their ori展开更多
本文旨在研究饲料蛋白水平、豆粕替代鱼粉对翘嘴红鲌(Erythroculter ilishaefor mis bleeker)消化酶活性的影响。以红鱼粉为饲料蛋白源,配制5个不同蛋白水平(31.04%、35.51%、40.89%、46.62%和50.33%)的等能、等必需氨基酸(EAA)平衡关...本文旨在研究饲料蛋白水平、豆粕替代鱼粉对翘嘴红鲌(Erythroculter ilishaefor mis bleeker)消化酶活性的影响。以红鱼粉为饲料蛋白源,配制5个不同蛋白水平(31.04%、35.51%、40.89%、46.62%和50.33%)的等能、等必需氨基酸(EAA)平衡关联度的的半精制饲料,研究蛋白水平对翘嘴红鲌消化酶活性的影响;又以豆粕替代鱼粉,大豆蛋白分别替代0.0%、13.5%、27.0%、40.5%、54.0%的鱼粉蛋白,配制5个等蛋白、等能和不同EAA关联度的半精制饲料,研究饲料中豆粕替代鱼粉对翘嘴红鲌消化酶活性的影响。试验结果表明,饲料蛋白水平对翘嘴红鲌肠道和肝胰脏的蛋白酶活性具有显著影响,肠道和肝胰脏蛋白酶活性随着饲料蛋白水平提高呈显著增强(P<0.05)。饲料蛋白水平为50.33%时,肠道蛋白酶活性最高,达171.26U/mgPr,显著高于31.04%饲料蛋白组(P<0.05);40.89%和46.62%饲料蛋白组的肝胰脏蛋白酶活性分别为35.04U/mgPr和35.68U/mgPr,显著高于31.04%和35.51%组(P<0.05)。饲料蛋白水平对肠道和肝胰脏的淀粉酶与脂肪酶活性没有显著影响(P>0.05)。饲料中豆粕替代鱼粉对翘嘴红鲌肠道和肝胰脏的蛋白酶活性具有显著影响,肝胰脏和肠道的蛋白酶活性都随着豆粕替代量提高而显著降低(P<0.05)。豆粕替代量为40.5%时,肠道蛋白酶活性为133.0U/mgPr,显著低于对照组(P<0.05),27.0%大豆蛋白替代组的肝胰脏的蛋白酶活性为31.34U/mgPr,显著低于对照组(P<0.05)。肠道淀粉酶活性没有受到豆粕替代鱼粉的影响(P>0.05),但肝胰脏淀粉酶活性随着豆粕替代量的提高而增强(P<0.05)。肝胰脏和肠道的脂肪酶活性不受饲料中豆粕替代鱼粉的影响(P>0.05)。展开更多
在翘嘴鲌（Culter alburnus）鱼种基础饲料中添加相当于抗坏血酸含量为0mg／kg、25mg／kg、50mg／kg、100mg／kg、150mg／kg、200mg／kg和400mg／kg的包膜维生素C（Vc），制成7种实验饲料，饲养初始体质量为（3．71±0．11）g的7组...在翘嘴鲌（Culter alburnus）鱼种基础饲料中添加相当于抗坏血酸含量为0mg／kg、25mg／kg、50mg／kg、100mg／kg、150mg／kg、200mg／kg和400mg／kg的包膜维生素C（Vc），制成7种实验饲料，饲养初始体质量为（3．71±0．11）g的7组翘嘴鲌鱼种8周，每个实验组包含3个重复。结果表明，摄食不添加Vc饲料的实验鱼成活率显著低于其他Vc添加组（P〈0．05）。饲料中Vc添加量为0-50mg／kg时，对鱼体增重有显著影响（P〈0．05），鱼体增重随添加量的增加而上升。但添加量继续增大，对鱼体增重不再有显著影响（P〉0．05）。饲料中维生素C添加量为。和25mg／kg时，饲料效率和蛋白质效率低于其他各组（P〈0．05）。试验饲料中Vc不同添加量对肝体指数和全鱼体成分无显著影响（P〉0．05）。肌肉中抗坏血酸含量随饲料中Vc添加量加大而不断上升，二者呈正相关关系（P〈0．05）。肝胰脏抗坏血酸含量在Vc添加量≤100mg／kg时，随饲料中Vc添加量加大而不断上升（P〈0．05），但高于此添加量时，则肝胰脏中抗坏血酸不再随添加量的上升而有显著变化（P〉0．05）。分别以鱼体增质量和肝胰脏中抗坏血酸为指标，经折线模型（Broken line model）回归分析求得翘嘴铂鱼种饲料中Vc的适宜添加量分别为53mg／kg和97mg／kg。展开更多
文摘Research was conducted on topmouth culter (Culter alburnus) grown in ponds and lakes as well as wild types in order to determine their chemical composition and nutritional value. There are three types of fish that differ in their proximate composition, amino acids, fatty acids, and minerals. Wild fish had a significantly lower crude lipid contents than cultured fish (P P ∑PUFAs) showed an obviously opposite trend. As compared with cultured fish, wild fish had significantly higher levels of n-3 PUFAs, arachidonic acid (AA), eicosapentaenoic acid (EPA) and docosahxaenoic acid (DHA) (P P > 0.05), except for Na, Fe and Se. In conclusion, diet composition and external aqueous environment may determine the differences between wild and cultured topmouth culter.
基金Supported by the National Key Technology Research and Development Program(No.2015BAD25B01)the Earmarked Fund for China Agriculture Research system(No.CARS-45)
文摘Geographic isolation is a key factor in shaping the genetic structure of many fish species.Two sympatric species,Culter alburnus and C.mongolicus,are economically important fish that are widely distributed in China and have been recently used as new aquaculture species.We used the mitochondrial DNA control region(CR)as a marker to investigate the genetic structure of the two species.Phylogenetic analysis revealed two major lineages(Lineages I and II)that were highly consistent with geographical patterns for C.alburnus and C.mongolicus.Based on genetic distance,the Zhujiang(Pearl)River Basin(ZRB)populations potentially represented a cryptic subspecies,which might be differentiated as the result of strict geographic isolation,an earlier diverged event,or peripheral areas.Genetic diversity analysis suggested that the Changjiang(Yangtze)River Basin(CRB)populations are located at,or near the core region of their origination,not only due to the larger population size at the CRB,but also their habitat diversity and suitability for its survival,and the genetic diversity dif ferences among basin populations were significant for the two species.Moreover,demographic analysis indicated that the two Culter species and most populations had undergone a period of population expansion during warm interglacial periods.However,the C.alburnus population of Huaihe River Basin(Weishan Lake)exhibited different patterns during the interglacial period,which may due to the latest diverged time of HRB and Weishan Lake located at the permafrost.Notably,the ZRB(in Songtao Reservoir)C.mongolicus population showed no genetic diversity and had a unique haplotype,which could be treated as a special gene pool for species conservation.In summary,geographic isolation is most likely responsible for the two Culter species distribution patterns.
基金Supported by Science and Technology Project of Jiangxi Province(20132BBF60051)
文摘[ Objective ] This study aimed to provide references for reasonable drug administration in Culter mongolicus and promote the development of its breeding industry. [Method] C. mongolicus was administrated with cypermethrin, mebendazole, trichlorfon, cupric sulfate, trichloroisocyanuric acid, povidone iodine and phoxim, respectively, to analyze its susceptibility to different drugs. [ Result] C. mongolicus was very sensitive to cypermethrin; the median tolerance limit （TLM） at 3,8 h was 0. 072mg/L, minimum lethal concentration was 0. 063 - 0. 069 mg,/L, safe concentration was 0. 021 6 mg/L. C. mongolicus was insensitive to mebendazole, trichlorfon, cupric sulfate, trichloroisocyanuric acid and povidone iodine. According to safe concentration of various drugs, C. mongolicus exhibited higher susceptibility to cypermethrin than to phoxim. [ Conclusion] This study laid a solid foundation for better protection and development of C. mongolicus resources.
基金Supported by the National Natural Science Foundation of China(No.41206124)the Ph.D Programs Foundation of Ministry of Education of China(No.23104120001)the "Chen Guang" Project(No.10CG52)
文摘The relationship between body size and stable isotopic signatures of the omnivorous Redfin Culter(C ultrichthys erythropterus),commonly found in East Lake Taihu,was investigated. Previous analyses of C. erythropterus stomach contents have shown that this species undergoes a diet switch from being predominantly zooplanktivorous to piscivorous during its life history. This was confirmed by stable carbon isotopic signature(δ 13 C) in this study,in which δ 13 C was positively correlated with both standard length and weight. The importance of littoral-benthic resources in supporting C. erythropterus during its lifespan was also demonstrated using a two-source mixing model,the results of which showed a significant increasing trend in the contribution of littoral-benthic energy. However,the stable nitrogen isotopic signature(δ 15N) exhibited an unusual pattern compared with previous studies. The δ 15 N of C. erythropterus showed no relationship with body size,even though dietary changes were observed. This indicated that δ 15 N alone cannot fully reflect a diet shift in a species and possible variability in isotopic signatures over its life history. This should be considered when using stable isotopic signatures to investigate intra-specific variations and the timing of life-history events,such as estimating the trophic positions of fish species.
文摘Many Ethiopian immigrants to Israel had their names changed to traditional Jewish names when arriving in Israel as children,as part of the melting pot conception.The purpose of the current study was to examine the perception of Jewish-Israeli identity among Jews of Ethiopian descent with the reverse name change they performed in adulthood.For this study,144 respondents were sampled,of whom 120 had had their name changed when immigrating to Israel.Of those whose name was changed,100 later changed their name back to the original name given by their parents.The study utilized an attitude questionnaire that sought to explore three research hypotheses.The first hypothesis was that the Jewish Israeli identity of those whose name had not been changed was stronger than that of those whose name was changed.With regard to this hypothesis,significant differences were found in the Jewish identity of those whose name had been changed and those who had not,such that those whose name had been changed portrayed a weaker sense of Israeli identity than those who had not.The second hypothesis was that those who changed their name back had a stronger Jewish Israeli identity than those who did not.The findings indicate that those who changed their name back show a weaker Jewish Israeli identity than those who decided not to revert to their original name.The third hypothesis was that various personal variables have an effect on the perception of Jewish identity,in addition to the name change.The control variables were not found to be significant,i.e.,sex and age had no significant influence on Jewish Israeli identity.These findings reinforce the findings concerning the previous hypotheses and indicate that Jewish Israeli identity is considerably connected to the name change.The main research finding is that the name change has an effect on the Jewish Israeli identity of Jews of Ethiopian descent,and this is a double effect.The outcomes of the name change cause these people to feel that they were forced to erase their culture,their ori
文摘本文旨在研究饲料蛋白水平、豆粕替代鱼粉对翘嘴红鲌(Erythroculter ilishaefor mis bleeker)消化酶活性的影响。以红鱼粉为饲料蛋白源,配制5个不同蛋白水平(31.04%、35.51%、40.89%、46.62%和50.33%)的等能、等必需氨基酸(EAA)平衡关联度的的半精制饲料,研究蛋白水平对翘嘴红鲌消化酶活性的影响;又以豆粕替代鱼粉,大豆蛋白分别替代0.0%、13.5%、27.0%、40.5%、54.0%的鱼粉蛋白,配制5个等蛋白、等能和不同EAA关联度的半精制饲料,研究饲料中豆粕替代鱼粉对翘嘴红鲌消化酶活性的影响。试验结果表明,饲料蛋白水平对翘嘴红鲌肠道和肝胰脏的蛋白酶活性具有显著影响,肠道和肝胰脏蛋白酶活性随着饲料蛋白水平提高呈显著增强(P<0.05)。饲料蛋白水平为50.33%时,肠道蛋白酶活性最高,达171.26U/mgPr,显著高于31.04%饲料蛋白组(P<0.05);40.89%和46.62%饲料蛋白组的肝胰脏蛋白酶活性分别为35.04U/mgPr和35.68U/mgPr,显著高于31.04%和35.51%组(P<0.05)。饲料蛋白水平对肠道和肝胰脏的淀粉酶与脂肪酶活性没有显著影响(P>0.05)。饲料中豆粕替代鱼粉对翘嘴红鲌肠道和肝胰脏的蛋白酶活性具有显著影响,肝胰脏和肠道的蛋白酶活性都随着豆粕替代量提高而显著降低(P<0.05)。豆粕替代量为40.5%时,肠道蛋白酶活性为133.0U/mgPr,显著低于对照组(P<0.05),27.0%大豆蛋白替代组的肝胰脏的蛋白酶活性为31.34U/mgPr,显著低于对照组(P<0.05)。肠道淀粉酶活性没有受到豆粕替代鱼粉的影响(P>0.05),但肝胰脏淀粉酶活性随着豆粕替代量的提高而增强(P<0.05)。肝胰脏和肠道的脂肪酶活性不受饲料中豆粕替代鱼粉的影响(P>0.05)。
文摘在翘嘴鲌（Culter alburnus）鱼种基础饲料中添加相当于抗坏血酸含量为0mg／kg、25mg／kg、50mg／kg、100mg／kg、150mg／kg、200mg／kg和400mg／kg的包膜维生素C（Vc），制成7种实验饲料，饲养初始体质量为（3．71±0．11）g的7组翘嘴鲌鱼种8周，每个实验组包含3个重复。结果表明，摄食不添加Vc饲料的实验鱼成活率显著低于其他Vc添加组（P〈0．05）。饲料中Vc添加量为0-50mg／kg时，对鱼体增重有显著影响（P〈0．05），鱼体增重随添加量的增加而上升。但添加量继续增大，对鱼体增重不再有显著影响（P〉0．05）。饲料中维生素C添加量为。和25mg／kg时，饲料效率和蛋白质效率低于其他各组（P〈0．05）。试验饲料中Vc不同添加量对肝体指数和全鱼体成分无显著影响（P〉0．05）。肌肉中抗坏血酸含量随饲料中Vc添加量加大而不断上升，二者呈正相关关系（P〈0．05）。肝胰脏抗坏血酸含量在Vc添加量≤100mg／kg时，随饲料中Vc添加量加大而不断上升（P〈0．05），但高于此添加量时，则肝胰脏中抗坏血酸不再随添加量的上升而有显著变化（P〉0．05）。分别以鱼体增质量和肝胰脏中抗坏血酸为指标，经折线模型（Broken line model）回归分析求得翘嘴铂鱼种饲料中Vc的适宜添加量分别为53mg／kg和97mg／kg。
