This paper reports the approprite ranges of Mg 2+, Ca 2+ and their ratio Mg 2+/Ca 2+ in mixed seawater for rearing of Penaeus japonicus larvae. The ranges for the above three indices are 1150-1450 mg/L, 360-440 mg/L a...This paper reports the approprite ranges of Mg 2+, Ca 2+ and their ratio Mg 2+/Ca 2+ in mixed seawater for rearing of Penaeus japonicus larvae. The ranges for the above three indices are 1150-1450 mg/L, 360-440 mg/L and 2.8-3.4, respectively. The proper salinity range of mixed seawater is 22.1-33.8 obtained by mixing estuarine water and concentrated seawater.展开更多
This study examined the distribution and elimination of Norfloxacin （NFLX） in Fenneropenaeus chinensis ovary and egg and newly hatched larvae. Mature parental shrimp were exposed to 4 or 10mgL-1 NFLX for 2 or 5d. Ov...This study examined the distribution and elimination of Norfloxacin （NFLX） in Fenneropenaeus chinensis ovary and egg and newly hatched larvae. Mature parental shrimp were exposed to 4 or 10mgL-1 NFLX for 2 or 5d. Ovary and eggs of the shrimp were sampled after spawning in order to detect NFLX residue using high-performance liquid chromatography （HPLC）. Re- suits showed that NFLX residue accumulated in F. chinensis eggs after the parental exposure, with the highest residue detected in ovary. To examine the fate of NFLX residue in larvae, we further determined the concentration of NFLX residue in F. chinensis eggs and larvae at 4 different developmental stages after 24-h exposure. From the newly metamorphosed larvae （Oh post-metamorphosis, h.p.m）, samples were taken at different time intervals to 72 h,p.m. HPLC assay showed that the concentrations of NFLX residue in zoea exposed to 4 and 10mgL-1 NFLX were the highest at 1.5h, i.e., 0.332 and 0.454μgg-1, respectively. At the two NFLX expo- sure levels, the elimination time of half NFLX （half life） in nauplius was 45.36 and 49.85h, respectively, followed by that in zoea （31.68 and 33.13 h）, mysis larvae （42.24 and 47.28 h） and postlarvae （24.48 and 30.96 h）. Both NFLX exposure levels had a germi- cidal effect. The distribution and elimination of NFLX residue in F. chinensis tissue, eggs and larvae correlated well with the drug exposure level. The disappearance of NFLX residue coincided with the larval growth, and the half-life of NFLX decreased with the larval development.展开更多
This study monitored the present status ofPenaeus monodon post larvae （PL.） of Kholpatua river in Satkhira. The survey was conducted in Kholpatua river from January 2014 to December 2014 and was compared with the te...This study monitored the present status ofPenaeus monodon post larvae （PL.） of Kholpatua river in Satkhira. The survey was conducted in Kholpatua river from January 2014 to December 2014 and was compared with the ten years old secondary data. The results showed that there was a 41.57% decrease in number of catches ofP. monodon PL. over the course of time from ten years ago to the year of 2014. Although the number of active fishermen＇s boats have increased from 250 to 360 in ten years. The study also showed that the severe shrimp seed collection activities reduced the availability ofP. monodon PL. at Satkhira district, which has a severe negative impact on the availability of total catches. To control such decrease of P. monodon PL. in Bangladesh, more intensive study should be done.展开更多
Studies have been carried out on the effect of lanthanum-amino acid complexes on embryo development and nauplius growth ofPenaeus chinensis. The experimental results indicate that: (1)The optimum concentrations of lan...Studies have been carried out on the effect of lanthanum-amino acid complexes on embryo development and nauplius growth ofPenaeus chinensis. The experimental results indicate that: (1)The optimum concentrations of lanthanum-proline and Lanthanumphenylalanine for the development of eggs in monocell and dicell stages are 1.50～ 4.00mg/L and 0.50～3.00 mg/L, respectively, the egg hatching rates being raised by 21.0 ～ 46.0% and 23.0 ～42.8% ( P ＜ 0.05 ) respectively. (2)The optimum concentrations of lanthanum- proline complex and Lanthanum-phenylalanine complex for the growth ofnauplii are 1.50～4.00 mg/L and 0.50～3.00 mg/L, the metamorphosis rate from nauplius to protozoea being raised by 16.4 ～27.5% and 20.4～26.7% (P ＜ 0.05 ) respectively. (3)The positive effect of lanthanum-amino acid complexes on egg hatching and nauplius metamorphosis of Penaeus chinensis is better than that of lanthanum. With regard to the positive effect, lanthanum-proline complex is better than Lanthanum-phenylalanine complex.展开更多
文摘This paper reports the approprite ranges of Mg 2+, Ca 2+ and their ratio Mg 2+/Ca 2+ in mixed seawater for rearing of Penaeus japonicus larvae. The ranges for the above three indices are 1150-1450 mg/L, 360-440 mg/L and 2.8-3.4, respectively. The proper salinity range of mixed seawater is 22.1-33.8 obtained by mixing estuarine water and concentrated seawater.
基金supported by the Earmarked Fund for Modern Agro-industry Technology Research System,China(No.CARS-47)the Special Fund for Agro-scientific Research in the Public Interest of China(No.201103034)
文摘This study examined the distribution and elimination of Norfloxacin （NFLX） in Fenneropenaeus chinensis ovary and egg and newly hatched larvae. Mature parental shrimp were exposed to 4 or 10mgL-1 NFLX for 2 or 5d. Ovary and eggs of the shrimp were sampled after spawning in order to detect NFLX residue using high-performance liquid chromatography （HPLC）. Re- suits showed that NFLX residue accumulated in F. chinensis eggs after the parental exposure, with the highest residue detected in ovary. To examine the fate of NFLX residue in larvae, we further determined the concentration of NFLX residue in F. chinensis eggs and larvae at 4 different developmental stages after 24-h exposure. From the newly metamorphosed larvae （Oh post-metamorphosis, h.p.m）, samples were taken at different time intervals to 72 h,p.m. HPLC assay showed that the concentrations of NFLX residue in zoea exposed to 4 and 10mgL-1 NFLX were the highest at 1.5h, i.e., 0.332 and 0.454μgg-1, respectively. At the two NFLX expo- sure levels, the elimination time of half NFLX （half life） in nauplius was 45.36 and 49.85h, respectively, followed by that in zoea （31.68 and 33.13 h）, mysis larvae （42.24 and 47.28 h） and postlarvae （24.48 and 30.96 h）. Both NFLX exposure levels had a germi- cidal effect. The distribution and elimination of NFLX residue in F. chinensis tissue, eggs and larvae correlated well with the drug exposure level. The disappearance of NFLX residue coincided with the larval growth, and the half-life of NFLX decreased with the larval development.
文摘This study monitored the present status ofPenaeus monodon post larvae （PL.） of Kholpatua river in Satkhira. The survey was conducted in Kholpatua river from January 2014 to December 2014 and was compared with the ten years old secondary data. The results showed that there was a 41.57% decrease in number of catches ofP. monodon PL. over the course of time from ten years ago to the year of 2014. Although the number of active fishermen＇s boats have increased from 250 to 360 in ten years. The study also showed that the severe shrimp seed collection activities reduced the availability ofP. monodon PL. at Satkhira district, which has a severe negative impact on the availability of total catches. To control such decrease of P. monodon PL. in Bangladesh, more intensive study should be done.
基金Supported by National Natural Science Fund of China (No: 39370548)
文摘Studies have been carried out on the effect of lanthanum-amino acid complexes on embryo development and nauplius growth ofPenaeus chinensis. The experimental results indicate that: (1)The optimum concentrations of lanthanum-proline and Lanthanumphenylalanine for the development of eggs in monocell and dicell stages are 1.50～ 4.00mg/L and 0.50～3.00 mg/L, respectively, the egg hatching rates being raised by 21.0 ～ 46.0% and 23.0 ～42.8% ( P ＜ 0.05 ) respectively. (2)The optimum concentrations of lanthanum- proline complex and Lanthanum-phenylalanine complex for the growth ofnauplii are 1.50～4.00 mg/L and 0.50～3.00 mg/L, the metamorphosis rate from nauplius to protozoea being raised by 16.4 ～27.5% and 20.4～26.7% (P ＜ 0.05 ) respectively. (3)The positive effect of lanthanum-amino acid complexes on egg hatching and nauplius metamorphosis of Penaeus chinensis is better than that of lanthanum. With regard to the positive effect, lanthanum-proline complex is better than Lanthanum-phenylalanine complex.
