This study was carried out in 2022 at the Itato agriculture community estate of fish hatchery in eastern Senegal with the aim of finding an alternative method to 17-α-methyl testosterone (MT) by using Garcinia kola ...This study was carried out in 2022 at the Itato agriculture community estate of fish hatchery in eastern Senegal with the aim of finding an alternative method to 17-α-methyl testosterone (MT) by using Garcinia kola “Bitter kola” powder to obtain Oreochromis niloticus male sex populations. 1800 fry of average size between 0.01 and 0.02 g were distributed in 12 aboveground tanks of 1 m3 each at a rate of 150 individuals/tank, following 6 duplicate treatments. The negative (B1 and B2) and positive (B3 and B4) control diets, to which between 0 and 60 mg/kg of 17alpha-methyl testosterone had been added respectively, were mixed with industrial feed containing 40% protein;the tank diets (B5 and B6), (B7 and B8), (B9 and B10) and (B11 and B12) contained 10 g, 20 g, 30 g and 40 g of Garcinia kola powder respectively for 1 kg of industrial feed con-taining 40% protein. These different treatments resulted in high proportions of males in the order of 97.03%;98.09% for the hormone and proportions of 94.03%;93.26% for 20 g of Garcinia kola extracts. In terms of weight growth, the best average weights for the hormone and Garcinia kola were 0.896 g and 0.980 g respectively. With regard to fish survival, the following results were recorded: 95.53% and 94.56% respectively for additions of 20 g and 30 g of Garcinia kola extracts to the feed supplied to the fish. On the other hand, a significant difference in the mortality rate of 35% and 5% respectively for the conventional hormone and 20 g of Garcinia kola extracts was observed. To conclude the study, it is recommended that further studies be carried out to determine the quality of the flesh, their life stages and the profile of the amino acids present in their proteins.展开更多
为比较星洲红鱼(Singapore red tilapia)和奥尼罗非鱼(Oreochromis niloticus)的生长和肌肉营养特性,实验利用两种鱼的不同体色将其混养在同一池塘中,在相同的环境条件和养殖管理下研究其生长特性,并分析肌肉营养成分。结果表明:两种罗...为比较星洲红鱼(Singapore red tilapia)和奥尼罗非鱼(Oreochromis niloticus)的生长和肌肉营养特性,实验利用两种鱼的不同体色将其混养在同一池塘中,在相同的环境条件和养殖管理下研究其生长特性,并分析肌肉营养成分。结果表明:两种罗非鱼生长在前60 d无差异,60 d后星洲红鱼的体长、体质量日增长和特定生长率均大于奥尼罗非鱼,且差异显著(P<0.05)。据此得到了星洲红鱼和奥尼罗非鱼的体长(L)、体质量(W)生长与养殖天数(d)的回归方程。星洲红鱼含肉率高于奥尼罗非鱼9.65%(P<0.05),肌肉水分高于奥尼罗非鱼,蛋白质、粗脂肪和灰分含量均低于奥尼罗非鱼,其中脂肪含量差异显著(P<0.05),其他不显著。两种罗非鱼肌肉的氨基酸组成全面,氨基酸组成均符合FAO/WHO的理想模式,除精氨酸含量有差异外,其他氨基酸含量稍有差异但不显著。星洲红鱼和奥尼罗非鱼肌肉EAA/TAA、EAA/NEAA、DAA/TAA和EAAI分别为41.04%和40.95%,70.00%和69.34%,40.71%和39.08%,67.46%和67.08%,差异不显著。星洲红鱼、奥尼罗非鱼肌肉∑SFA和∑UFA分别为28.03%和28.60%,63.87%和61.38%,各脂肪酸含量除C14:0和C18:2外,其他含量差异不显著。研究表明,星洲红鱼和奥尼罗非鱼生长快、营养丰富、食用价值高,是优质淡水鱼类养殖品种,其中星洲红鱼含肉率高,生长快,养殖效益明显。展开更多
The effects of phenanthrene（Phe） on hepatosomatic index（HSI） and hepatic enzymatic activities in hybrid tilapia（Oreochromis niloticus ♀× O.aureus ♂） were investigated via the static freshwater exposure at...The effects of phenanthrene（Phe） on hepatosomatic index（HSI） and hepatic enzymatic activities in hybrid tilapia（Oreochromis niloticus ♀× O.aureus ♂） were investigated via the static freshwater exposure at dosage of 50,100,and 400 μg/L for 4-14 d.Compared with the control group,HSI was significantly decreased（P 〈 0.05） at 400 μg/L at day 14.Increased enzymatic activities（P 〈 0.05） were observed for catalase（CAT）,glutathione peroxidase（GPx） and superoxide dismutase（SOD） at either 100 or 400 μg/L at day 8 and 14,as well as for CAT at 50 μg/L at day 14,except for GPx at 400 μg/L at day 8.Ethoxyresorufin O-deethylase（EROD） activity was significantly increased（P 〈 0.05） at all dosage at day 4 as well as at 50 μg/L at day 8,but significantly decreased at either 100 or 400 μg/L at day 14（P 〈 0.05）.Glutathione-S-transferase（GST） activity was not affected.The results suggest that CAT,GPx,SOD and EROD,as well as HSI in tilapia may be used as the biomarkers or indexes for evaluating or monitoring the pollution of polycyclic aromatic hydrocarbons（PAHs） such as Phe.展开更多
The efficacy of Endocrine Disrupting Compounds (EDCs), 17β-estradiol was tested on the fish Oreochromis niloticus in order to understand the intersex relationship of fish, in which sequential hermaphrodism can consis...The efficacy of Endocrine Disrupting Compounds (EDCs), 17β-estradiol was tested on the fish Oreochromis niloticus in order to understand the intersex relationship of fish, in which sequential hermaphrodism can consist of a male changing into a female (protandry) or a female changing into a male (protogyny). The fish were equally divided into 3 groups. The first group was the control group;the second and third groups were treated with 10 and 100 mg L-1 of 17β-estradiol, respectively, for 30 days. The overall result in this experiment had no significant effect on the growth parameters. Among the two treated groups, the low concentration group shows results similar to those of the control groups. The high concentration group shows changes to the male reproductive system with the appearance of the testis-ova present resulting in an intersex condition of the male gonads. With this experiment, it can be concluded that 17β-estradiol at high concentration reveals positive changes towards the male reproductive system of the fish, Oreochromis niloticus.展开更多
We present results of a long-term study aimed to optimize Nile tilapia O. niloticus production in a recirculating aquaculture system (RAS) in México City. Three experiments were evaluated: 1) fry production;2) pr...We present results of a long-term study aimed to optimize Nile tilapia O. niloticus production in a recirculating aquaculture system (RAS) in México City. Three experiments were evaluated: 1) fry production;2) production of masculinized fries;and 3) assessment of growth under three different densities (10, 30 and 75 fish/m3). The broodstock produced on average 2400 ± 600 fry every 15 days during six months, with a total production of 28,800 ± 2000. One hundred percent males were produced in 274-L raceways in an eight-week period. The obtained results in fish production in the RAS system indicated variations related to density. A daily growth rate of 3.6 g/day was registered with a density of 10 fish/m3, 0.9 g/day in 30 fish/m3 and 0.4 g/day in 75 fish/m3. This information could be useful for production purposes in this type of systems.展开更多
性类固醇激素对动物生长有一定的影响,但其对鱼类雌、雄生长差异的影响机理尚不清楚。为进一步了解动物雌雄生长差异的内在原因,本文通过在体注射和荧光定量PCR方法,比较了性类固醇激素(E_2、MT)对尼罗罗非鱼雌鱼和雄鱼的生长及对垂体G...性类固醇激素对动物生长有一定的影响,但其对鱼类雌、雄生长差异的影响机理尚不清楚。为进一步了解动物雌雄生长差异的内在原因,本文通过在体注射和荧光定量PCR方法,比较了性类固醇激素(E_2、MT)对尼罗罗非鱼雌鱼和雄鱼的生长及对垂体GH、肝脏GHR1、IGF-I m RNA表达的影响。结果表明:性类固醇激素E2和MT对尼罗罗非鱼的生长及生长轴相关基因的表达均有显著的影响,并且这种影响存在明显的性别二态性。E_2明显促进雌鱼的生长但不显著影响雄鱼的生长,MT显著促进雄鱼和雌鱼的生长;E2可使雌鱼垂体GH和肝脏GHR1、IGF-I的m RNA水平显著升高(P<0.05),但降低雄鱼垂体GH和肝脏GHR1的m RNA表达;MT显著提高雄鱼垂体GH和肝脏GHR1、IGF-I m RNA水平(P<0.05),但降低雌鱼垂体GH的m RNA表达,促进雌鱼肝脏GHR1 m RNA的表达,但对雄鱼肝脏GHR1的促进作用明显大于雌鱼(P<0.05)。上述结果表明,性类固醇激素对不同性别尼罗罗非鱼的生长及生长轴相关基因的m RNA表达有不同的影响,表现出明显的性别二态性,提示不同性别鱼体内性类固醇激素水平的不同可能是导致尼罗罗非鱼雌雄生长二态性的另一内在原因。展开更多
为了研究不同盐度下尼罗罗非鱼(Oreochromis niloticus)、萨罗罗非鱼(Sarotherodon melanotheron)和以色列红罗非鱼(Israel red tilapia)幼鱼生长的影响,试验选择尼罗罗非鱼、萨罗罗非鱼和以色列红罗非鱼幼苗各150尾。初始平均体重分别...为了研究不同盐度下尼罗罗非鱼(Oreochromis niloticus)、萨罗罗非鱼(Sarotherodon melanotheron)和以色列红罗非鱼(Israel red tilapia)幼鱼生长的影响,试验选择尼罗罗非鱼、萨罗罗非鱼和以色列红罗非鱼幼苗各150尾。初始平均体重分别为(2.74±0.12)g、(2.69±0.10)g和(2.75±0.11)g。试验共设置5个盐度水平,分别为0‰、10‰、20‰、30‰、40‰。每种鱼每个盐度30尾,并设置3个平行小组。试验为期60 d。结果显示,终末体重和日均增重量以M0(1)组的最高,其生长速度显著的高于其它处理小组(P<0.05)。除处理M10(1)组外,其它均达到极显著水平(P<0.01)。M0(2)、M10(2)、M40(1)和M40(3)的生长速度则显著的慢于其它各个处理小组,其中经过对比,生长速度最快和生长速度最慢相比相差了4倍。成活率和肥满度以M0(2)、M10(2)、M20(2)、M30(2)和M40(2)相对显著高于其它几个处理小组(P<0.05)。在不同盐度梯度下,对3种鱼进行饲养,其终末体重、日均增重、成活率和肥满系数指标均存在显著性差异(P<0.05),说明盐度和罗非鱼品种对罗非鱼的生长速度、成活率和肥满度均有显著影响。在5种盐度下,萨罗罗非鱼的成活率高于以色列红罗非鱼和尼罗罗非鱼,萨罗罗非鱼的肥满系数显著高于尼罗罗非鱼和以色列红罗非鱼,以色列红罗非鱼与尼罗罗非鱼的肥满系数没有显著差异。该研究发现,尼罗罗非鱼和以色列红罗非鱼在低盐度水中生长快,萨罗罗非鱼在高盐度水中生长快。展开更多
文摘This study was carried out in 2022 at the Itato agriculture community estate of fish hatchery in eastern Senegal with the aim of finding an alternative method to 17-α-methyl testosterone (MT) by using Garcinia kola “Bitter kola” powder to obtain Oreochromis niloticus male sex populations. 1800 fry of average size between 0.01 and 0.02 g were distributed in 12 aboveground tanks of 1 m3 each at a rate of 150 individuals/tank, following 6 duplicate treatments. The negative (B1 and B2) and positive (B3 and B4) control diets, to which between 0 and 60 mg/kg of 17alpha-methyl testosterone had been added respectively, were mixed with industrial feed containing 40% protein;the tank diets (B5 and B6), (B7 and B8), (B9 and B10) and (B11 and B12) contained 10 g, 20 g, 30 g and 40 g of Garcinia kola powder respectively for 1 kg of industrial feed con-taining 40% protein. These different treatments resulted in high proportions of males in the order of 97.03%;98.09% for the hormone and proportions of 94.03%;93.26% for 20 g of Garcinia kola extracts. In terms of weight growth, the best average weights for the hormone and Garcinia kola were 0.896 g and 0.980 g respectively. With regard to fish survival, the following results were recorded: 95.53% and 94.56% respectively for additions of 20 g and 30 g of Garcinia kola extracts to the feed supplied to the fish. On the other hand, a significant difference in the mortality rate of 35% and 5% respectively for the conventional hormone and 20 g of Garcinia kola extracts was observed. To conclude the study, it is recommended that further studies be carried out to determine the quality of the flesh, their life stages and the profile of the amino acids present in their proteins.
基金supported by the National Natural Science Foundation of China (No. 30570325,30671629)the Science and Technology Project of Guangdong Province (No.2005B20301013, 2006A36502004,2007B090400049)
文摘The effects of phenanthrene（Phe） on hepatosomatic index（HSI） and hepatic enzymatic activities in hybrid tilapia（Oreochromis niloticus ♀× O.aureus ♂） were investigated via the static freshwater exposure at dosage of 50,100,and 400 μg/L for 4-14 d.Compared with the control group,HSI was significantly decreased（P 〈 0.05） at 400 μg/L at day 14.Increased enzymatic activities（P 〈 0.05） were observed for catalase（CAT）,glutathione peroxidase（GPx） and superoxide dismutase（SOD） at either 100 or 400 μg/L at day 8 and 14,as well as for CAT at 50 μg/L at day 14,except for GPx at 400 μg/L at day 8.Ethoxyresorufin O-deethylase（EROD） activity was significantly increased（P 〈 0.05） at all dosage at day 4 as well as at 50 μg/L at day 8,but significantly decreased at either 100 or 400 μg/L at day 14（P 〈 0.05）.Glutathione-S-transferase（GST） activity was not affected.The results suggest that CAT,GPx,SOD and EROD,as well as HSI in tilapia may be used as the biomarkers or indexes for evaluating or monitoring the pollution of polycyclic aromatic hydrocarbons（PAHs） such as Phe.
文摘The efficacy of Endocrine Disrupting Compounds (EDCs), 17β-estradiol was tested on the fish Oreochromis niloticus in order to understand the intersex relationship of fish, in which sequential hermaphrodism can consist of a male changing into a female (protandry) or a female changing into a male (protogyny). The fish were equally divided into 3 groups. The first group was the control group;the second and third groups were treated with 10 and 100 mg L-1 of 17β-estradiol, respectively, for 30 days. The overall result in this experiment had no significant effect on the growth parameters. Among the two treated groups, the low concentration group shows results similar to those of the control groups. The high concentration group shows changes to the male reproductive system with the appearance of the testis-ova present resulting in an intersex condition of the male gonads. With this experiment, it can be concluded that 17β-estradiol at high concentration reveals positive changes towards the male reproductive system of the fish, Oreochromis niloticus.
基金Financial support was provided by the Division de Ciencias Biologicas y de la Salud,UAM-Iztapalapa.
文摘We present results of a long-term study aimed to optimize Nile tilapia O. niloticus production in a recirculating aquaculture system (RAS) in México City. Three experiments were evaluated: 1) fry production;2) production of masculinized fries;and 3) assessment of growth under three different densities (10, 30 and 75 fish/m3). The broodstock produced on average 2400 ± 600 fry every 15 days during six months, with a total production of 28,800 ± 2000. One hundred percent males were produced in 274-L raceways in an eight-week period. The obtained results in fish production in the RAS system indicated variations related to density. A daily growth rate of 3.6 g/day was registered with a density of 10 fish/m3, 0.9 g/day in 30 fish/m3 and 0.4 g/day in 75 fish/m3. This information could be useful for production purposes in this type of systems.
文摘性类固醇激素对动物生长有一定的影响,但其对鱼类雌、雄生长差异的影响机理尚不清楚。为进一步了解动物雌雄生长差异的内在原因,本文通过在体注射和荧光定量PCR方法,比较了性类固醇激素(E_2、MT)对尼罗罗非鱼雌鱼和雄鱼的生长及对垂体GH、肝脏GHR1、IGF-I m RNA表达的影响。结果表明:性类固醇激素E2和MT对尼罗罗非鱼的生长及生长轴相关基因的表达均有显著的影响,并且这种影响存在明显的性别二态性。E_2明显促进雌鱼的生长但不显著影响雄鱼的生长,MT显著促进雄鱼和雌鱼的生长;E2可使雌鱼垂体GH和肝脏GHR1、IGF-I的m RNA水平显著升高(P<0.05),但降低雄鱼垂体GH和肝脏GHR1的m RNA表达;MT显著提高雄鱼垂体GH和肝脏GHR1、IGF-I m RNA水平(P<0.05),但降低雌鱼垂体GH的m RNA表达,促进雌鱼肝脏GHR1 m RNA的表达,但对雄鱼肝脏GHR1的促进作用明显大于雌鱼(P<0.05)。上述结果表明,性类固醇激素对不同性别尼罗罗非鱼的生长及生长轴相关基因的m RNA表达有不同的影响,表现出明显的性别二态性,提示不同性别鱼体内性类固醇激素水平的不同可能是导致尼罗罗非鱼雌雄生长二态性的另一内在原因。
