The effects of natural fish oil, DHA oil and soybean lecithin in microparticulate diets on stress tolerance of larval gilthead seabream ( Sparus aurata ) were investigated after 15 days feeding trials. The tolerance o...The effects of natural fish oil, DHA oil and soybean lecithin in microparticulate diets on stress tolerance of larval gilthead seabream ( Sparus aurata ) were investigated after 15 days feeding trials. The tolerance of larval gilthead seabream to various stress factors such as exposure to air ( lack of dissolved oxygen), changes in water temperature (low) and salinity ( high) were determined. This study showed that microparticulate diet with natural fish oil and soybean lecithin was the most effective for increasing the tolerance of larval gilthead seabream to various stresses, and that microparticulate diet with natural fish oil and palmitic acid (16:0) was more effective than microparticulate diet with DHA oil and soybean lecithin.展开更多
Objective:To determine the amount of azinphos methyl and diazinon residues in two river fishes,Liza aurata and Cyprinus carpio,in the north of Iran.Methods:This study was done during2006-2007.In this survey,152 water ...Objective:To determine the amount of azinphos methyl and diazinon residues in two river fishes,Liza aurata and Cyprinus carpio,in the north of Iran.Methods:This study was done during2006-2007.In this survey,152 water and fish samples from Gorgan and Qarasu rivers,north of Iran,were investigated.Sampling was done in three predetermined stations along each river.Organophosphorus compounds(OPs)were extracted from the fishes and the water of rivers.After extraction,purification and concentration processes,the amount and type of insecticides in water and fish samples were determined by high performance thin layer chromatography(HPTLC).Results:There was a significant difference in the residue of the insecticides in the water and fish samples between summer and other seasons in the two rivers.The highest amount of insecticides residue was seen during summer.In both rivers,the amount of diazinon and azinphos methyl residues in the two fishes was more than 2000 mg/L in summer.There was no significant difference in insecticides residue between the fishes in two rivers.The diazinon residue was higher than the standard limits in both rivers during the spring and the summer,but the residual amount of azinphos methyl was higher than the standard limits only during the summer and only in Qarasu River.Conclusions:It can be concluded that the amount of OPs in the water and the two fishes,Liza aurata and Cyprinus carpio,is higher than the permitted levels.展开更多
以生长于重庆缙云山国家级自然保护区内的粉叶新木姜子(Neolitsea aurata var.glauca Yang)和四川大头茶〔Polyspora speciosa(Kochs)B.M.Barthol.et T.L.Ming〕2年生幼苗为实验材料,研究了不同p H值的模拟酸雨对叶片气体交换参数、光...以生长于重庆缙云山国家级自然保护区内的粉叶新木姜子(Neolitsea aurata var.glauca Yang)和四川大头茶〔Polyspora speciosa(Kochs)B.M.Barthol.et T.L.Ming〕2年生幼苗为实验材料,研究了不同p H值的模拟酸雨对叶片气体交换参数、光响应曲线和光响应参数的影响,并比较了2树种对模拟酸雨的抗性。结果表明:四川大头茶叶片的各项气体交换参数和光响应参数总体上高于粉叶新木姜子。随模拟酸雨p H值降低,粉叶新木姜子叶片的净光合速率(Pn)、气孔导度(Gs)和蒸腾速率(Tr)逐渐降低且总体上显著低于对照(p H 5.6模拟酸雨);四川大头茶叶片的Pn、Gs和Tr值在p H 2.0模拟酸雨作用下显著低于对照、在p H 3.5模拟酸雨作用下显著高于对照;但不同p H值模拟酸雨对2树种叶片的水分利用效率总体上无显著影响。经不同p H值模拟酸雨处理后2树种叶片的光响应曲线与对照明显不同。与对照相比,经p H 2.0、p H 2.5和p H 3.5模拟酸雨处理后粉叶新木姜子叶片的最大净光合速率(Pmax)、光饱和点(LSP)和表观量子产量(AQY)总体上显著降低,光补偿点(LCP)显著升高;其暗呼吸速率(Rd)在p H 2.0和p H 3.5模拟酸雨作用下显著高于对照、在p H 2.5模拟酸雨作用下显著低于对照。四川大头茶叶片的Pmax和LSP值在p H 2.0和p H 2.5模拟酸雨作用下显著低于对照,但在p H 3.5模拟酸雨作用下显著高于对照;其LCP和Rd值在p H 2.5和p H 3.5模拟酸雨作用下显著低于对照,但在p H 2.0模拟酸雨作用下均高于对照;其AQY值在p H 2.0、p H 2.5和p H 3.5模拟酸雨作用下均低于对照。研究结果显示:酸性较强(p H 2.0和p H 2.5)的模拟酸雨均可抑制2树种的光合作用,而酸性较弱(p H 3.5)的模拟酸雨对四川大头茶的光合作用有一定的促进作用,表明四川大头茶对酸雨的抗性相对强于粉叶新木姜子。展开更多
Mesocosm hatcheries using semi-intensive culture methodologies are characterized by large tanks （40 m3） for fish larvae production at low densities （2-8 larvae/L）, with live prey production within the tank supplem...Mesocosm hatcheries using semi-intensive culture methodologies are characterized by large tanks （40 m3） for fish larvae production at low densities （2-8 larvae/L）, with live prey production within the tank supplemented by exogenous sources of feed. Due to the high biological quality of larvae produced and low level of technological input, these methodologies are regarded as an interesting option to meet the increasing fry demand from the aquaculture industry. This study aimed to describe the experience at Centro de Maricultura da Calheta, Madeira Island, Portugal, with the establishment of a mesocosm hatchery for the production of marine fish larvae. Production trials were initiated with gilthead seabream Sparus aurata. This larval species presented faster growth in total body length （TL） per day （TL = 3.7516e~ ~293day, R2 = 0.9404）, higher survival rate （SR = 31.9%） and comparable swimbladder inflation rates （SB = 90%） to those of larvae reared with intensive methodologies. High larval performance was obtained with two candidate species for aquaculture： the red porgy Pagruspagrus （TL = 3.212e~~39day, R2 = 0.995; SR = 15.3%; SB = 95.7%） and the white seabream Diplodus sargus （TL = 3.6355e~~413day, R2= 0.9824; SR = 25%; SB --- 100%）. Testing ofa 110 m3 mesocosm rearing tank with white seabream larvae revealed limitations associated to larger tanks namely, the amount and quality of live feed required daily. First trials with striped jack （Pseudocararoc dentex） larvae resulted in low larval survival （0.04%）, but the use of a white tank avoided culture management constraints related to positive phototropism. The present results suggest that a mesocosm using semi-intensive methodologies may contribute to species diversification and consequently, to the sustainable development of aquaculture.展开更多
Spawning performance-relative fecundity and fertilization success-was studied in two hatchery-reared broodstocks of gilthead seabream(Sparus aurata)held under relatively constant well-water temperature(18-20◦C)and sim...Spawning performance-relative fecundity and fertilization success-was studied in two hatchery-reared broodstocks of gilthead seabream(Sparus aurata)held under relatively constant well-water temperature(18-20◦C)and simulated natural photoperiod,for five consecutive spawning seasons,between 3 and 7 years of age.The spawning season lasted between 4 and 6 months each year,and the total number of eggs produced annually ranged between 1480000 and 3100000 eggs/kg female body weight,being the highest during the first and second spawning season.No difference was observed in monthly relative fecundity between years-although high variation existed within years,whereas fertilization success was the highest during the second and third reproductive season,and dropped significantly during the last year of the study.The male percentage of the broodstocks was 35%during the first spawning season of the females,and thereafter it decreased further and remained stable at around 15%-20%for the second and third spawning season.Substitution of older females with smaller males to readjust male percentage to 50%in the fourth spawning season,was followed by sex change of larger males to females and a drop of the male percentage to 18%in the following spawning season.The present study demonstrated the long spawning season of gilthead seabream-especially under constant water temperature,the high fecundity and fertilization success,and the stabilization of male percentage to~20%after the first spawning season or when a broodstock is modified to increase male percentage.These results are useful to the aquaculture industry,demonstrating that there is no need to add males to gilthead seabream broodstocks over the years,as the sex ratio is stabilized and egg production and fertilization success remain high with a relatively low male:female sex ratio.展开更多
Objective:To determine the concentration of heavy metals(Cd,Cu,Fe,Ni,Pb and Zn)in the liver,gills and muscle of Liza aurata(L.aurata)collected from the Kerkennah Islands.The target hazard quotient was also used as an ...Objective:To determine the concentration of heavy metals(Cd,Cu,Fe,Ni,Pb and Zn)in the liver,gills and muscle of Liza aurata(L.aurata)collected from the Kerkennah Islands.The target hazard quotient was also used as an indicator of human health risks associated with fish consumption.Methods:The sample was collected from Kerkennah Islands(Gulf of Gabes,Tunisia).Heavy metals in L.aurata tissues(gills,liver and muscle)were analysed with an atomic absorption spectrometer(PerkinElmer).Results:As expected,muscle always possessed the lowest concentrations of all metals.The maximum concentrations of Cd(0.52 mg/kg wet weight),Cu(5.43 mg/kg wet weight),Fe(115.27mg/kg wet weight)and Zn(112.20 mg/kg wet weight)were measured in the liver,while the highest Ni(1.54 mg/kg wet weight)and Pb(1.43 mg/kg wet weight)were recorded in gills.The target hazard quotient through consumption of fish and calculated by adding the inividual target hazard quotient was below 1,indicating that there was no significant potential health risk associated with consumption of L.aurata.Conclusions:L.aurata from the Kerkennah Islands may be suitable for human consumption.展开更多
文摘The effects of natural fish oil, DHA oil and soybean lecithin in microparticulate diets on stress tolerance of larval gilthead seabream ( Sparus aurata ) were investigated after 15 days feeding trials. The tolerance of larval gilthead seabream to various stress factors such as exposure to air ( lack of dissolved oxygen), changes in water temperature (low) and salinity ( high) were determined. This study showed that microparticulate diet with natural fish oil and soybean lecithin was the most effective for increasing the tolerance of larval gilthead seabream to various stresses, and that microparticulate diet with natural fish oil and palmitic acid (16:0) was more effective than microparticulate diet with DHA oil and soybean lecithin.
基金supported by the Faculty of Public Health,Tehran University of Medical Sciences(grant No.TUMS/HF/2009/8811)
文摘Objective:To determine the amount of azinphos methyl and diazinon residues in two river fishes,Liza aurata and Cyprinus carpio,in the north of Iran.Methods:This study was done during2006-2007.In this survey,152 water and fish samples from Gorgan and Qarasu rivers,north of Iran,were investigated.Sampling was done in three predetermined stations along each river.Organophosphorus compounds(OPs)were extracted from the fishes and the water of rivers.After extraction,purification and concentration processes,the amount and type of insecticides in water and fish samples were determined by high performance thin layer chromatography(HPTLC).Results:There was a significant difference in the residue of the insecticides in the water and fish samples between summer and other seasons in the two rivers.The highest amount of insecticides residue was seen during summer.In both rivers,the amount of diazinon and azinphos methyl residues in the two fishes was more than 2000 mg/L in summer.There was no significant difference in insecticides residue between the fishes in two rivers.The diazinon residue was higher than the standard limits in both rivers during the spring and the summer,but the residual amount of azinphos methyl was higher than the standard limits only during the summer and only in Qarasu River.Conclusions:It can be concluded that the amount of OPs in the water and the two fishes,Liza aurata and Cyprinus carpio,is higher than the permitted levels.
文摘以生长于重庆缙云山国家级自然保护区内的粉叶新木姜子(Neolitsea aurata var.glauca Yang)和四川大头茶〔Polyspora speciosa(Kochs)B.M.Barthol.et T.L.Ming〕2年生幼苗为实验材料,研究了不同p H值的模拟酸雨对叶片气体交换参数、光响应曲线和光响应参数的影响,并比较了2树种对模拟酸雨的抗性。结果表明:四川大头茶叶片的各项气体交换参数和光响应参数总体上高于粉叶新木姜子。随模拟酸雨p H值降低,粉叶新木姜子叶片的净光合速率(Pn)、气孔导度(Gs)和蒸腾速率(Tr)逐渐降低且总体上显著低于对照(p H 5.6模拟酸雨);四川大头茶叶片的Pn、Gs和Tr值在p H 2.0模拟酸雨作用下显著低于对照、在p H 3.5模拟酸雨作用下显著高于对照;但不同p H值模拟酸雨对2树种叶片的水分利用效率总体上无显著影响。经不同p H值模拟酸雨处理后2树种叶片的光响应曲线与对照明显不同。与对照相比,经p H 2.0、p H 2.5和p H 3.5模拟酸雨处理后粉叶新木姜子叶片的最大净光合速率(Pmax)、光饱和点(LSP)和表观量子产量(AQY)总体上显著降低,光补偿点(LCP)显著升高;其暗呼吸速率(Rd)在p H 2.0和p H 3.5模拟酸雨作用下显著高于对照、在p H 2.5模拟酸雨作用下显著低于对照。四川大头茶叶片的Pmax和LSP值在p H 2.0和p H 2.5模拟酸雨作用下显著低于对照,但在p H 3.5模拟酸雨作用下显著高于对照;其LCP和Rd值在p H 2.5和p H 3.5模拟酸雨作用下显著低于对照,但在p H 2.0模拟酸雨作用下均高于对照;其AQY值在p H 2.0、p H 2.5和p H 3.5模拟酸雨作用下均低于对照。研究结果显示:酸性较强(p H 2.0和p H 2.5)的模拟酸雨均可抑制2树种的光合作用,而酸性较弱(p H 3.5)的模拟酸雨对四川大头茶的光合作用有一定的促进作用,表明四川大头茶对酸雨的抗性相对强于粉叶新木姜子。
文摘Mesocosm hatcheries using semi-intensive culture methodologies are characterized by large tanks （40 m3） for fish larvae production at low densities （2-8 larvae/L）, with live prey production within the tank supplemented by exogenous sources of feed. Due to the high biological quality of larvae produced and low level of technological input, these methodologies are regarded as an interesting option to meet the increasing fry demand from the aquaculture industry. This study aimed to describe the experience at Centro de Maricultura da Calheta, Madeira Island, Portugal, with the establishment of a mesocosm hatchery for the production of marine fish larvae. Production trials were initiated with gilthead seabream Sparus aurata. This larval species presented faster growth in total body length （TL） per day （TL = 3.7516e~ ~293day, R2 = 0.9404）, higher survival rate （SR = 31.9%） and comparable swimbladder inflation rates （SB = 90%） to those of larvae reared with intensive methodologies. High larval performance was obtained with two candidate species for aquaculture： the red porgy Pagruspagrus （TL = 3.212e~~39day, R2 = 0.995; SR = 15.3%; SB = 95.7%） and the white seabream Diplodus sargus （TL = 3.6355e~~413day, R2= 0.9824; SR = 25%; SB --- 100%）. Testing ofa 110 m3 mesocosm rearing tank with white seabream larvae revealed limitations associated to larger tanks namely, the amount and quality of live feed required daily. First trials with striped jack （Pseudocararoc dentex） larvae resulted in low larval survival （0.04%）, but the use of a white tank avoided culture management constraints related to positive phototropism. The present results suggest that a mesocosm using semi-intensive methodologies may contribute to species diversification and consequently, to the sustainable development of aquaculture.
基金supported by an internal program (GnRHa implants,60.70101)from the Institute of Marine Biology,Biotechnology and Aquaculture of the Hellenic Center for Marine Research to CCM.
文摘Spawning performance-relative fecundity and fertilization success-was studied in two hatchery-reared broodstocks of gilthead seabream(Sparus aurata)held under relatively constant well-water temperature(18-20◦C)and simulated natural photoperiod,for five consecutive spawning seasons,between 3 and 7 years of age.The spawning season lasted between 4 and 6 months each year,and the total number of eggs produced annually ranged between 1480000 and 3100000 eggs/kg female body weight,being the highest during the first and second spawning season.No difference was observed in monthly relative fecundity between years-although high variation existed within years,whereas fertilization success was the highest during the second and third reproductive season,and dropped significantly during the last year of the study.The male percentage of the broodstocks was 35%during the first spawning season of the females,and thereafter it decreased further and remained stable at around 15%-20%for the second and third spawning season.Substitution of older females with smaller males to readjust male percentage to 50%in the fourth spawning season,was followed by sex change of larger males to females and a drop of the male percentage to 18%in the following spawning season.The present study demonstrated the long spawning season of gilthead seabream-especially under constant water temperature,the high fecundity and fertilization success,and the stabilization of male percentage to~20%after the first spawning season or when a broodstock is modified to increase male percentage.These results are useful to the aquaculture industry,demonstrating that there is no need to add males to gilthead seabream broodstocks over the years,as the sex ratio is stabilized and egg production and fertilization success remain high with a relatively low male:female sex ratio.
文摘Objective:To determine the concentration of heavy metals(Cd,Cu,Fe,Ni,Pb and Zn)in the liver,gills and muscle of Liza aurata(L.aurata)collected from the Kerkennah Islands.The target hazard quotient was also used as an indicator of human health risks associated with fish consumption.Methods:The sample was collected from Kerkennah Islands(Gulf of Gabes,Tunisia).Heavy metals in L.aurata tissues(gills,liver and muscle)were analysed with an atomic absorption spectrometer(PerkinElmer).Results:As expected,muscle always possessed the lowest concentrations of all metals.The maximum concentrations of Cd(0.52 mg/kg wet weight),Cu(5.43 mg/kg wet weight),Fe(115.27mg/kg wet weight)and Zn(112.20 mg/kg wet weight)were measured in the liver,while the highest Ni(1.54 mg/kg wet weight)and Pb(1.43 mg/kg wet weight)were recorded in gills.The target hazard quotient through consumption of fish and calculated by adding the inividual target hazard quotient was below 1,indicating that there was no significant potential health risk associated with consumption of L.aurata.Conclusions:L.aurata from the Kerkennah Islands may be suitable for human consumption.
