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
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 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.
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。
文摘在试验水温为(25±2)℃时,以150 mg.kg-1的剂量给奥尼罗非鱼单次口灌硫酸新霉素,采用高效液相色谱法测定血浆和肌肉组织中的药物浓度,研究了硫酸新霉素在奥尼罗非鱼体内代谢及消除的规律.结果表明:血药时间数据符合一级吸收二室开放模型,半衰期(T1/2Ka、T1/2α、T1/2β)分别为1.05、2.05、11.94 h,最大血药浓度为7.013μg.mL-1,达峰时间为2.856 h,药时曲线下面积(AUC)为101.22μg.h.mL-1.选取肌肉组织作为残留检测的靶组织,以欧盟残留限量500μg.kg-1为最高残留限量,在本试验条件下,建议休药期不低于7 d.
