Population dynamics parameters and stock status of Squaliobarbus curriculus (Richardson, 1846) were analyzed from May to September 2021 in the Lanxi section of Qiantang River. FiSAT II software program was used. The g...Population dynamics parameters and stock status of Squaliobarbus curriculus (Richardson, 1846) were analyzed from May to September 2021 in the Lanxi section of Qiantang River. FiSAT II software program was used. The growth coefficient K = 0.21 year<sup>–1</sup>, asymptomatic length L<sub>∞</sub> = 39.48 cm, and age at theoretical zero-length t<sub>0</sub> = –0.74 years were estimated. The von Bertalanffy growth function was calculated as L<sub>t</sub> = 39.48[1 – e<sup>–</sup><sup>0.21(t + 0.74)</sup>]. The growth curve for weight had an inflection at 5.86 years, corresponding to 29.61 cm in standard length and 372.29 g in weight. The natural mortality rate (M), the fishing mortality rate (F), and the total mortality rate (Z) were calculated as 0.51, 0.61, and 1.12 year<sup>–1</sup>, respectively. The exploitation ratio (E) was 0.54, which is greater than the value of 0.5 suggested by Gull (1971), indicating a probable state of overdevelopment. The annual average stock number and biomass of S. curriculus in the Lanxi section of Qiantang River were 31.86 × 10<sup>6</sup> individuals and 3656.82 t, respectively.展开更多
A nucleic acid sequence-based amplification(NASBA)assay was established for the detection of Macrobrachium rosenbergii Nodavirus(MrNV).The specific primers were designed according to the high conserved region of R...A nucleic acid sequence-based amplification(NASBA)assay was established for the detection of Macrobrachium rosenbergii Nodavirus(MrNV).The specific primers were designed according to the high conserved region of RNA2 sequence of MrNV.The 224 bp specific amplification product was obtained in positive sample determined with 3%agarose gel electrophoresis,while no product was generated from shrimp infected with other viruses including DNA viruses(IHHNV,WSSV)and RNA viruses(TSV,IMNV,YHV).The detecting limit of the assay was 8pg nucleic acid,which is more sensitive than that of PCR method.展开更多
文摘Population dynamics parameters and stock status of Squaliobarbus curriculus (Richardson, 1846) were analyzed from May to September 2021 in the Lanxi section of Qiantang River. FiSAT II software program was used. The growth coefficient K = 0.21 year<sup>–1</sup>, asymptomatic length L<sub>∞</sub> = 39.48 cm, and age at theoretical zero-length t<sub>0</sub> = –0.74 years were estimated. The von Bertalanffy growth function was calculated as L<sub>t</sub> = 39.48[1 – e<sup>–</sup><sup>0.21(t + 0.74)</sup>]. The growth curve for weight had an inflection at 5.86 years, corresponding to 29.61 cm in standard length and 372.29 g in weight. The natural mortality rate (M), the fishing mortality rate (F), and the total mortality rate (Z) were calculated as 0.51, 0.61, and 1.12 year<sup>–1</sup>, respectively. The exploitation ratio (E) was 0.54, which is greater than the value of 0.5 suggested by Gull (1971), indicating a probable state of overdevelopment. The annual average stock number and biomass of S. curriculus in the Lanxi section of Qiantang River were 31.86 × 10<sup>6</sup> individuals and 3656.82 t, respectively.
基金Supported by Special Fund for Agro-scientific Research in the Public Interest(201103034)Huzhou Science and Technology Project(2012GN08,2011ZD2005)Science and Technology Innovation Team Project of Freshwater Aquaculture of Zhejiang Province(2012R10026-11)
文摘A nucleic acid sequence-based amplification(NASBA)assay was established for the detection of Macrobrachium rosenbergii Nodavirus(MrNV).The specific primers were designed according to the high conserved region of RNA2 sequence of MrNV.The 224 bp specific amplification product was obtained in positive sample determined with 3%agarose gel electrophoresis,while no product was generated from shrimp infected with other viruses including DNA viruses(IHHNV,WSSV)and RNA viruses(TSV,IMNV,YHV).The detecting limit of the assay was 8pg nucleic acid,which is more sensitive than that of PCR method.