Hybrid tilapia weighing 7.71 g were reared in seawater at 24.0-29.0℃ for 8 weeks. The controls were fed to satiation twice a day throughout the experiment, whereas treatment groups were fed at 0.5%, 1.5% or 3.0% body...Hybrid tilapia weighing 7.71 g were reared in seawater at 24.0-29.0℃ for 8 weeks. The controls were fed to satiation twice a day throughout the experiment, whereas treatment groups were fed at 0.5%, 1.5% or 3.0% body weight per day for 4 weeks, and then to satiation for the remainder of the experiment. During the first 4-week period, there was a curvilinear relationship between growth rate and ration size. Fish fed 0.5% and 1.5% rations displayed compensatory growth response of 2 weeks duration during realimentation. The weight-adjusted growth rate of fish fed at 3% ration was not significantly different from that of the controls by the end of the experiment, when none of the treatment groups had caught up in body weight with the controls. Hyperphagia was observed for the first 2 weeks of realimenatation in fish previously fed at 3% ration, but persisted for the whole realimentation period in groups previously fed at 0.5% and 1.5% rations. None of the feed restricted groups showed improved digestibility, feed efficiency, or protein and energy retention efficiency.展开更多
Insects,particularly black soldier fly larvae(BSFM),Hermetia illucens,have been regarded as promising protein and lipid sources in animal feed,including fish.Digestibility is the key factor that affects nutrient utili...Insects,particularly black soldier fly larvae(BSFM),Hermetia illucens,have been regarded as promising protein and lipid sources in animal feed,including fish.Digestibility is the key factor that affects nutrient utilization,feeding physiology and efficiency.In the present work,the effect of BSFM on the digestibility of red hybrid tilapia(RHT)compared to fish meal(FM)was ultimately unveiled.A 56-day growth trial was performed with 60 RHT(~30 g)randomly distributed into six tanks and fed two experimental diets containing FM as a reference diet and BSFM as a test diet.In addition,faeces were collected to determine their chromium concentration and proximate composition.The apparent digestibility coefficient(ADC)of dry matter,crude protein and energy in the BSFM diet were observed to be significantly higher than those in the FM diet.Besides,the growth performance of fish fed with the BSFM diet exhibited significantly higher(P<0.05)weight gain,specific growth rate,protein efficiency ratio and lower feed conversion ratio than those in the FM group.This study shows that the BSFM feed was well digested by tilapia and improved its growth performance.展开更多
This study investigated the effect of dietary supplementation of yeast nucleotides on the growth, nonspecific immunity, intestine growth and intestinal microbiota of juvenile hybrid tilapia. Tilapia(initial average we...This study investigated the effect of dietary supplementation of yeast nucleotides on the growth, nonspecific immunity, intestine growth and intestinal microbiota of juvenile hybrid tilapia. Tilapia(initial average weight of 8.02 g) was fed test diets supplemented with a yeast-originated nucleotide mixture(0,0.15, 0.30, 0.60, and 1.20 g/100 g diet) for 8 weeks. Fish fed the diet with 0.60% nucleotide had significantly higher weight gain than the control group(P < 0.05). Feed efficiency was improved in the fish fed 0.60 and 1.20% nucleotide compared with that in the control group. The optimal doses of nucleotides supplementation for growth and feed efficiency of fish were determined as 0.63 and 0.81%, respectively.Intestinal growth was improved in the 0.30 and 0.60% groups, as indicated by significant increase in intestine length. The fish fed 0.60 and 1.20% nucleotide showed higher super oxide dismutase(SOD)activity and lower malondialdehyde(MDA) level in the liver than the control fish, indicating enhancement of the anti-oxidant status. Serum lysozyme activity was significantly increased in the 0.15 and 0.3%nucleotide supplementation groups, suggesting an enhancement effect on the non-specific immune response. Lastly, dietary nucleotides supplementation exerted moderate influence on the intestinal microbiota of hybrid tilapia. A reduction in the cumulative abundance of putative butyrate-producing species was observed in the intestinal microbiota of fish fed diets with 0.60% nucleotide compared with the control, implying an interaction between dietary nucleotides and butyrate production. Briefly, dietary supplementation with 0.60% nucleotide improve the growth performance, immune activity and intestine growth in tilapia.展开更多
[Objectives]This study was conducted to construct forward and reserve libraries of suppression subtractive hybridization (SSH) in the testis of male tilapia under the stress of methomyl by using SSH technology.[Method...[Objectives]This study was conducted to construct forward and reserve libraries of suppression subtractive hybridization (SSH) in the testis of male tilapia under the stress of methomyl by using SSH technology.[Methods]Using male tilapia as the test animal,the forward and reserve libraries of SSH in the testis of tilapia under the stress of methomyl were constructed by using the SSH technology.[Results]45 expressed sequence tags (ESTs) were obtained,and 25 expressed sequence tags were successfully noted,including 13 forward libraries and 12 reverse libraries.The genes with confirmed functions were classified into five types.Genes related to catalytic activity and cell characteristics were up-regulated,while genes related to structural molecule's activity and biological process were down-regulated.The expression amount of integrin β1 was up-regulated,while serine/threonine protein kinase pim-3,Ca^2+-ATPase,Na^+-K^+-ATPase and ribosomal protein L22 were down-regulated.[Conclusions]The research results could lay a foundation for revealing the molecular mechanism of methomyl's reproductive toxicity to tilapia.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
用5种浓度的十二烷基苯磺酸钠(sodiumdodecyl benzene sulfonic,SDBS)浸泡刺激奥尼罗非鱼(Tilapianilotica♀×T.aurea♂)8周,每2周采血样1次,测定免疫指标。0.05和0.10mg·L-1组对奥尼罗非鱼的氯化硝基四氮唑兰(nitro blue tet...用5种浓度的十二烷基苯磺酸钠(sodiumdodecyl benzene sulfonic,SDBS)浸泡刺激奥尼罗非鱼(Tilapianilotica♀×T.aurea♂)8周,每2周采血样1次,测定免疫指标。0.05和0.10mg·L-1组对奥尼罗非鱼的氯化硝基四氮唑兰(nitro blue tetrazolium,NBT)阳性细胞和IgM含量无影响。0.40mg·L-1组在第8周时,IgM含量显著下降,而NBT阳性细胞突然急剧下降,与对照组相比差异极显著。0.70mg·L-1组从第4周起,NBT阳性细胞和IgM含量开始减少,第6周时差异显著。1.00mg·L-1组NBT阳性细胞数在第2周时量就已经有减少,但与对照组相比差异不显著,到第4周时差异极其显著;在第4周时IgM含量有显著差异,第6周后差异极显著。攻毒试验表明,0.40、0.70和1.00mg·L-1组的死亡率均高于对照组。以上结果表明,当SDBS浓度大于0.40mg·L-1时,奥尼罗非鱼免疫功能不同程度受到抑制,对NBT阳性细胞和IgM的影响存在着时间与剂量效应。展开更多
基金Supported by the State Key Laboratory of Freshwater Ecology and Biotechnology of China and Shanghai Fisheries University (Grant No. 200015).
文摘Hybrid tilapia weighing 7.71 g were reared in seawater at 24.0-29.0℃ for 8 weeks. The controls were fed to satiation twice a day throughout the experiment, whereas treatment groups were fed at 0.5%, 1.5% or 3.0% body weight per day for 4 weeks, and then to satiation for the remainder of the experiment. During the first 4-week period, there was a curvilinear relationship between growth rate and ration size. Fish fed 0.5% and 1.5% rations displayed compensatory growth response of 2 weeks duration during realimentation. The weight-adjusted growth rate of fish fed at 3% ration was not significantly different from that of the controls by the end of the experiment, when none of the treatment groups had caught up in body weight with the controls. Hyperphagia was observed for the first 2 weeks of realimenatation in fish previously fed at 3% ration, but persisted for the whole realimentation period in groups previously fed at 0.5% and 1.5% rations. None of the feed restricted groups showed improved digestibility, feed efficiency, or protein and energy retention efficiency.
基金Ministry of Higher Education Malaysia for the Fundamental Research Grant Scheme (FRGS/1/2019/WAB01/UM/02/3)and FP073-2019A awarded to Dr Norhidayah Mohd Taufek.
文摘Insects,particularly black soldier fly larvae(BSFM),Hermetia illucens,have been regarded as promising protein and lipid sources in animal feed,including fish.Digestibility is the key factor that affects nutrient utilization,feeding physiology and efficiency.In the present work,the effect of BSFM on the digestibility of red hybrid tilapia(RHT)compared to fish meal(FM)was ultimately unveiled.A 56-day growth trial was performed with 60 RHT(~30 g)randomly distributed into six tanks and fed two experimental diets containing FM as a reference diet and BSFM as a test diet.In addition,faeces were collected to determine their chromium concentration and proximate composition.The apparent digestibility coefficient(ADC)of dry matter,crude protein and energy in the BSFM diet were observed to be significantly higher than those in the FM diet.Besides,the growth performance of fish fed with the BSFM diet exhibited significantly higher(P<0.05)weight gain,specific growth rate,protein efficiency ratio and lower feed conversion ratio than those in the FM group.This study shows that the BSFM feed was well digested by tilapia and improved its growth performance.
基金supported by grants from the National Science and Technology Support Program Project of China (2014CB138600, 2012BAD25B02, 2015CB150605)the National Natural Science Foundation of China (31272672 to ZGZ)the Beijing Earmarked Fund for Modern Agro-industry Technology Research System (SCGWZJ20141104-4)
文摘This study investigated the effect of dietary supplementation of yeast nucleotides on the growth, nonspecific immunity, intestine growth and intestinal microbiota of juvenile hybrid tilapia. Tilapia(initial average weight of 8.02 g) was fed test diets supplemented with a yeast-originated nucleotide mixture(0,0.15, 0.30, 0.60, and 1.20 g/100 g diet) for 8 weeks. Fish fed the diet with 0.60% nucleotide had significantly higher weight gain than the control group(P < 0.05). Feed efficiency was improved in the fish fed 0.60 and 1.20% nucleotide compared with that in the control group. The optimal doses of nucleotides supplementation for growth and feed efficiency of fish were determined as 0.63 and 0.81%, respectively.Intestinal growth was improved in the 0.30 and 0.60% groups, as indicated by significant increase in intestine length. The fish fed 0.60 and 1.20% nucleotide showed higher super oxide dismutase(SOD)activity and lower malondialdehyde(MDA) level in the liver than the control fish, indicating enhancement of the anti-oxidant status. Serum lysozyme activity was significantly increased in the 0.15 and 0.3%nucleotide supplementation groups, suggesting an enhancement effect on the non-specific immune response. Lastly, dietary nucleotides supplementation exerted moderate influence on the intestinal microbiota of hybrid tilapia. A reduction in the cumulative abundance of putative butyrate-producing species was observed in the intestinal microbiota of fish fed diets with 0.60% nucleotide compared with the control, implying an interaction between dietary nucleotides and butyrate production. Briefly, dietary supplementation with 0.60% nucleotide improve the growth performance, immune activity and intestine growth in tilapia.
基金Supported by Basic Scientific Research Fund for Chinese Academy of Fishery Sciences(2015C02XK01)Youth Natural Scientific Foundation of Jiansu Province(BK20150117)Earmarked Fund for China Agriculture Research System(CARS-46)
文摘[Objectives]This study was conducted to construct forward and reserve libraries of suppression subtractive hybridization (SSH) in the testis of male tilapia under the stress of methomyl by using SSH technology.[Methods]Using male tilapia as the test animal,the forward and reserve libraries of SSH in the testis of tilapia under the stress of methomyl were constructed by using the SSH technology.[Results]45 expressed sequence tags (ESTs) were obtained,and 25 expressed sequence tags were successfully noted,including 13 forward libraries and 12 reverse libraries.The genes with confirmed functions were classified into five types.Genes related to catalytic activity and cell characteristics were up-regulated,while genes related to structural molecule's activity and biological process were down-regulated.The expression amount of integrin β1 was up-regulated,while serine/threonine protein kinase pim-3,Ca^2+-ATPase,Na^+-K^+-ATPase and ribosomal protein L22 were down-regulated.[Conclusions]The research results could lay a foundation for revealing the molecular mechanism of methomyl's reproductive toxicity to tilapia.
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.
文摘用5种浓度的十二烷基苯磺酸钠(sodiumdodecyl benzene sulfonic,SDBS)浸泡刺激奥尼罗非鱼(Tilapianilotica♀×T.aurea♂)8周,每2周采血样1次,测定免疫指标。0.05和0.10mg·L-1组对奥尼罗非鱼的氯化硝基四氮唑兰(nitro blue tetrazolium,NBT)阳性细胞和IgM含量无影响。0.40mg·L-1组在第8周时,IgM含量显著下降,而NBT阳性细胞突然急剧下降,与对照组相比差异极显著。0.70mg·L-1组从第4周起,NBT阳性细胞和IgM含量开始减少,第6周时差异显著。1.00mg·L-1组NBT阳性细胞数在第2周时量就已经有减少,但与对照组相比差异不显著,到第4周时差异极其显著;在第4周时IgM含量有显著差异,第6周后差异极显著。攻毒试验表明,0.40、0.70和1.00mg·L-1组的死亡率均高于对照组。以上结果表明,当SDBS浓度大于0.40mg·L-1时,奥尼罗非鱼免疫功能不同程度受到抑制,对NBT阳性细胞和IgM的影响存在着时间与剂量效应。
