The Yangtze River estuary is the main production area of Anguilla japonica in China,as well as the only existing fishery area for adult eels.Japanese eels are distributed in the main rivers and many tributaries from t...The Yangtze River estuary is the main production area of Anguilla japonica in China,as well as the only existing fishery area for adult eels.Japanese eels are distributed in the main rivers and many tributaries from the Yangtze River estuary to the upper Jinsha River,which extend to nearly 3 000 km.However,their migration behaviors remain relatively unknown.We analyzed the biological characteristics of 153 specimens of silver eels collected from the Jingjiang section of Yangtze River（31o30＇N,120o42＇E） between September and November,2008,and tested the sagittal Sr/Ca ratios of 27 specimens.Among the 153 specimens examined,85 were female and 68 were male,which translated to a female-male ratio of 1：0.8.The ages of the female specimens ranged from 3 to 7 a（average 5.52） with an average total length（TL） of（669±80） mm,average body weight（BW） of（555±229）g,average condition factor of 1.77±0.22,and average gonad somatic index（GSI） of 1.32±0.31.The ages of the males ranged from 3 to 5 a（average：4.38） with an average TL of（518±51） mm,average BW of（234±76） g,average condition factor of 1.62±0.18,and average GSI of 0.21±0.11.All biological parameters of females were significantly larger than those of the male specimens（P0.05）.According to the average Sr/Ca ratio（7.99±1.05） ×10-3 of the elver mark of sagitta,17 individuals（62.96%） were river eels and 10 individuals（37.04%） were estuarine eels.Of 16 females,13 individuals（81.25%） were river eels and 3 were estuarine eels,while of 11 males,36.36% were river eels and 63.64% were estuarine eels.The analysis on Sr/Ca ratios for every growth layer group（GLG） indicated there were no significant differences between second-age males and females.However,significant differences were observed between the third-age,fourth-age,and migration-age male and female specimens.This was likely related to the fact that second-age eels of both sexes stay in the same inhabitation waters;however,as they grow older,they move to different areas.展开更多
[Objective]The mechanism of alkaline phosphatase（ALP） was studied to promote rice-field eel aquaculture industry. [ Method] The effects of effectors such as multiple metal ions and organic solvents on ALP in viscera...[Objective]The mechanism of alkaline phosphatase（ALP） was studied to promote rice-field eel aquaculture industry. [ Method] The effects of effectors such as multiple metal ions and organic solvents on ALP in viscera of rice-field eel. [ Result] Na^＋ and K ^＋ didn＇t generate big influences on enzyme activity;Mg^2＋ and Ca^2＋ could promote ALP while Li^＋,Cu^2＋ and Zn^2＋ could restrain ALP enzyme activity. Both HPO4^2- and WO4^2- generated by en- zyme catalyzing disodium phenyl phosphate possessed strong inhibitory effects on emzymc, and 9.5 mmol/L HPO4^2 - would make enzyme activity decline by 13% while 9.5 mmol/L WO4^3- would make enzyme decline by 34%. The inhibition types of them were both competitive inhibition on enzyme activity. The organic solvents such as methanol, ethanol,ethylene glycol,isopropannl all generated influences on ALP and the order according to their inhibitory effects was isopropanol 〉 ethanol 〉 methanol 〉 ethylene glycol. [ Conclusion] The inflncnces of various effeetors on ALP aetivity of rice-field eel were studied from dynamics perspective to provide theoretical basis for further clarifying ALP mechanism.展开更多
[Objective] The aim was to find a suitable weaning regime, including weaning period and weaning feed, for Angui//a mormorata glass eels. [Method] A weaning processing experiment was conducted indoor in fiberglass tank...[Objective] The aim was to find a suitable weaning regime, including weaning period and weaning feed, for Angui//a mormorata glass eels. [Method] A weaning processing experiment was conducted indoor in fiberglass tanks, two kinds of artificial feeds （eel grower powder feed and eel grower piece feed） were selected as weaning diets against a control group fed on natural food （minced octopus flesh）, two weaning periods, 5 and 15 d, were introduced in weaning experiment. [Result] The growth rate and survival rate of the groups with 15-day＇s weaning period were higher than that of the groups with 5-day＇s weaning period, revealing that a 20% increase every 3 d from 0% to 100% in the proportion of grower paste in the minced octopus flesh during weaning is suitable for A. mormorata glass eels. [Conclusion] A. mormorata glass eels can be weaned from natural food to the commer- cially available eel grower feeds over a certain weaning period, and of the artificial feeds with same ingredients and nutrient, A. mormorata glass eels accepted powder feed more readily over 28 d than piece feed.展开更多
In order to evaluate the involvement of the thyroid gland in reproduction, thyroid functioning was described in female cultivated Japanese eel (Anguilla japonica) in progressive stages of sexual maturation induced by ...In order to evaluate the involvement of the thyroid gland in reproduction, thyroid functioning was described in female cultivated Japanese eel (Anguilla japonica) in progressive stages of sexual maturation induced by chum salmon pituitary homogenate (SPH) treatment. Serum thyroid hormones, thyroxine (T4) and triiodothyronine (T3) were also measured in each stage. Thyroid gland activity (epithelial cell height) was high before SPH injection (previtellogenic stage), further increasing at the early vitellogenic stage, thereafter decreasing to late vitellogenic and migratory nucleus stages. The profiles of both T3 and T4 changed during vitellogenesis, being high during previtellogenic and early vitellogenic stages, and subsequently declining, thus mimicking thyroid gland activity. These results suggest that the thyroid has relation with eel ovarian development during artificial maturation.展开更多
Eel family is a huge one, in which many kinds of eelsespecially some migratory eels, bear strong resemblance toeach other, and are therefOre difficult to be identified. Inthis study 29 random primers were used to make...Eel family is a huge one, in which many kinds of eelsespecially some migratory eels, bear strong resemblance toeach other, and are therefOre difficult to be identified. Inthis study 29 random primers were used to make RAPDana1ysis for Japanese ee1 (Angui11ajaponica). European eel(Anguilla anguilla) and Pike eel (AIllrae1lesox cinereus).And totally 299 fragments were counted. Shared or spe-cific fragments were counted alld ge11etic similarity or ge-netic distance were calculated. The genetic similarity be-tween Japanese eel alld Pike eel is 0.68 and the geneticdistance between them is 0.32; those between Europeaneel and Pike eel are 0.72 and 0.28 respectively, and be-tween Japanese eel and Ellropean eel are 0.74 and 0.25 re-spectively. The method has been shown to be suitable tomolecular identification of eels. It provides an a1ternativeapproach to determine the relatiollship between species.展开更多
The present study aimed at making a rational usage for European eel bone by-products by preparing Europen eel bone peptide chelated calcium(EBPC-Ca).Nutritional properties and bioactivity of EBPC-Ca were evaluated.Res...The present study aimed at making a rational usage for European eel bone by-products by preparing Europen eel bone peptide chelated calcium(EBPC-Ca).Nutritional properties and bioactivity of EBPC-Ca were evaluated.Results showed that nutritional properties of calcium ions will cause intra-and inter-molecular folding and aggregation of peptide to uniformly form EBPC-Ca chelate.The chelated compound of EBPC and calcium ion triggered a strong apoptosis in heterogeneous human epithelial colorectal adenocarcinoma(Caco-2)in concentration-and time-dependent manners.Western blot analysis revealed that the EBPC-Ca induced apoptosis may be the result of a blocked autophagy flux through mitochondrial-dependent pathway.Additionally,the increase in FGF-23 protein expression inhibited the absorption of calcium ions and alleviated cell apoptosis.It was also found that the cell apoptosis occurs with significant increases in the levels of reactive oxygen species(ROS)and Ca^(2+)in the cells,indicating the anti-tumor potential of EBPC-Ca may involve multiple channels.展开更多
基金supported by the Chinese National Science Foundation under the Grant(30771650)the Key Programs of Science and Technology Commission Foundation of Shanghai(08391910200)+3 种基金Special Fund for Agroscientific Research in the Public Interest(201203065)Research Fund for the Doctoral Program of Higher Education of China(20070264001)E-class Programs of Shanghai Municipal Education Commission(E03009)the Key Subject Construction of Shanghai(S30701)
文摘The Yangtze River estuary is the main production area of Anguilla japonica in China,as well as the only existing fishery area for adult eels.Japanese eels are distributed in the main rivers and many tributaries from the Yangtze River estuary to the upper Jinsha River,which extend to nearly 3 000 km.However,their migration behaviors remain relatively unknown.We analyzed the biological characteristics of 153 specimens of silver eels collected from the Jingjiang section of Yangtze River（31o30＇N,120o42＇E） between September and November,2008,and tested the sagittal Sr/Ca ratios of 27 specimens.Among the 153 specimens examined,85 were female and 68 were male,which translated to a female-male ratio of 1：0.8.The ages of the female specimens ranged from 3 to 7 a（average 5.52） with an average total length（TL） of（669±80） mm,average body weight（BW） of（555±229）g,average condition factor of 1.77±0.22,and average gonad somatic index（GSI） of 1.32±0.31.The ages of the males ranged from 3 to 5 a（average：4.38） with an average TL of（518±51） mm,average BW of（234±76） g,average condition factor of 1.62±0.18,and average GSI of 0.21±0.11.All biological parameters of females were significantly larger than those of the male specimens（P0.05）.According to the average Sr/Ca ratio（7.99±1.05） ×10-3 of the elver mark of sagitta,17 individuals（62.96%） were river eels and 10 individuals（37.04%） were estuarine eels.Of 16 females,13 individuals（81.25%） were river eels and 3 were estuarine eels,while of 11 males,36.36% were river eels and 63.64% were estuarine eels.The analysis on Sr/Ca ratios for every growth layer group（GLG） indicated there were no significant differences between second-age males and females.However,significant differences were observed between the third-age,fourth-age,and migration-age male and female specimens.This was likely related to the fact that second-age eels of both sexes stay in the same inhabitation waters;however,as they grow older,they move to different areas.
基金Science and Techndogy Fund of Chongqing Science and Technology cmmission~~
文摘[Objective]The mechanism of alkaline phosphatase（ALP） was studied to promote rice-field eel aquaculture industry. [ Method] The effects of effectors such as multiple metal ions and organic solvents on ALP in viscera of rice-field eel. [ Result] Na^＋ and K ^＋ didn＇t generate big influences on enzyme activity;Mg^2＋ and Ca^2＋ could promote ALP while Li^＋,Cu^2＋ and Zn^2＋ could restrain ALP enzyme activity. Both HPO4^2- and WO4^2- generated by en- zyme catalyzing disodium phenyl phosphate possessed strong inhibitory effects on emzymc, and 9.5 mmol/L HPO4^2 - would make enzyme activity decline by 13% while 9.5 mmol/L WO4^3- would make enzyme decline by 34%. The inhibition types of them were both competitive inhibition on enzyme activity. The organic solvents such as methanol, ethanol,ethylene glycol,isopropannl all generated influences on ALP and the order according to their inhibitory effects was isopropanol 〉 ethanol 〉 methanol 〉 ethylene glycol. [ Conclusion] The inflncnces of various effeetors on ALP aetivity of rice-field eel were studied from dynamics perspective to provide theoretical basis for further clarifying ALP mechanism.
基金Supported by Xiamen Marine Research and Development Institute [K10102(1)]~~
文摘[Objective] The aim was to find a suitable weaning regime, including weaning period and weaning feed, for Angui//a mormorata glass eels. [Method] A weaning processing experiment was conducted indoor in fiberglass tanks, two kinds of artificial feeds （eel grower powder feed and eel grower piece feed） were selected as weaning diets against a control group fed on natural food （minced octopus flesh）, two weaning periods, 5 and 15 d, were introduced in weaning experiment. [Result] The growth rate and survival rate of the groups with 15-day＇s weaning period were higher than that of the groups with 5-day＇s weaning period, revealing that a 20% increase every 3 d from 0% to 100% in the proportion of grower paste in the minced octopus flesh during weaning is suitable for A. mormorata glass eels. [Conclusion] A. mormorata glass eels can be weaned from natural food to the commer- cially available eel grower feeds over a certain weaning period, and of the artificial feeds with same ingredients and nutrient, A. mormorata glass eels accepted powder feed more readily over 28 d than piece feed.
文摘In order to evaluate the involvement of the thyroid gland in reproduction, thyroid functioning was described in female cultivated Japanese eel (Anguilla japonica) in progressive stages of sexual maturation induced by chum salmon pituitary homogenate (SPH) treatment. Serum thyroid hormones, thyroxine (T4) and triiodothyronine (T3) were also measured in each stage. Thyroid gland activity (epithelial cell height) was high before SPH injection (previtellogenic stage), further increasing at the early vitellogenic stage, thereafter decreasing to late vitellogenic and migratory nucleus stages. The profiles of both T3 and T4 changed during vitellogenesis, being high during previtellogenic and early vitellogenic stages, and subsequently declining, thus mimicking thyroid gland activity. These results suggest that the thyroid has relation with eel ovarian development during artificial maturation.
文摘Eel family is a huge one, in which many kinds of eelsespecially some migratory eels, bear strong resemblance toeach other, and are therefOre difficult to be identified. Inthis study 29 random primers were used to make RAPDana1ysis for Japanese ee1 (Angui11ajaponica). European eel(Anguilla anguilla) and Pike eel (AIllrae1lesox cinereus).And totally 299 fragments were counted. Shared or spe-cific fragments were counted alld ge11etic similarity or ge-netic distance were calculated. The genetic similarity be-tween Japanese eel alld Pike eel is 0.68 and the geneticdistance between them is 0.32; those between Europeaneel and Pike eel are 0.72 and 0.28 respectively, and be-tween Japanese eel and Ellropean eel are 0.74 and 0.25 re-spectively. The method has been shown to be suitable tomolecular identification of eels. It provides an a1ternativeapproach to determine the relatiollship between species.
基金supported by National Natural Science Foundation of China(NSFC,Grant No.31801459,Grant No.32072209)China Postdoctoral Science Foundation Funded Project(2020M682073)+1 种基金the Science and Technology General Projects of Fujian Province(2019J01393)Program of Innovative Research Team in Science and Technology in Fujian Province University([2020]12)。
文摘The present study aimed at making a rational usage for European eel bone by-products by preparing Europen eel bone peptide chelated calcium(EBPC-Ca).Nutritional properties and bioactivity of EBPC-Ca were evaluated.Results showed that nutritional properties of calcium ions will cause intra-and inter-molecular folding and aggregation of peptide to uniformly form EBPC-Ca chelate.The chelated compound of EBPC and calcium ion triggered a strong apoptosis in heterogeneous human epithelial colorectal adenocarcinoma(Caco-2)in concentration-and time-dependent manners.Western blot analysis revealed that the EBPC-Ca induced apoptosis may be the result of a blocked autophagy flux through mitochondrial-dependent pathway.Additionally,the increase in FGF-23 protein expression inhibited the absorption of calcium ions and alleviated cell apoptosis.It was also found that the cell apoptosis occurs with significant increases in the levels of reactive oxygen species(ROS)and Ca^(2+)in the cells,indicating the anti-tumor potential of EBPC-Ca may involve multiple channels.
