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Science China(Life Sciences) 2017年第11期60卷 1260-1270页

作者： suxu he quanmin wang shuning li chao ran xiaoze guo zhen zhang zhigang zhou key laboratory for feed biotechnology of the ministry of agriclture feed research institutechinese academy of agricutural sciencesBeijing 100081China

Low dose antibiotics have been used as growth promoters in livestock and fish. The use of antibiotics has been associated with reduced pathogen infections in livestock. In contrast, antibiotic growth promoter has been suspected of leading to disease outbreaks in aquaculture. However, this phenomenon is circumstantial and has not been confirmed in experimental conditions. In this study,we showed that antibiotic olaquindox increased the susceptibility of zebrafish to A. hydrophila infection. Olaquindox led to profound alterations in the intestinal microbiota of zebrafish, with a drastic bloom of Enterobacter and diminishing of Cetobacterium. Moreover, the innate immune responses of zebrafish were compromised by olaquindox(Phe immuo-suppression effect of olaquindox is a combined effect mediated by both OLA-altered micro biota and direct action of the antibiotic(Phe increased pathogen susceptibility was driven by the OLA-altered microbiota and was not dependent on direct antibiotic effect. Taken together, these data indicate that low level of OLA induced gut microbiota dysbiosis in zebrafish, which led to increased pathogen susceptibility.

关键词： antibiotic growth promoter pathogen susceptability gut microbiota fish olaquindox

Effects of dietary yeast nucleotides on growth, non-specific immunity intestine growth and intestinal microbiota of juvenile hybrid tilapia Oreochromis niloticus ♀ × Oreochromis aureus ♂

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Animal Nutrition 2015年第3期1卷 244-251页

作者： Li Xu Chao Ran suxu he Jianli Zhang Jun Hu Yalin Yang Zhenyu Du Yanou Yang Zhigang Zhou Key Laboratory for Feed Biotechnology of the Ministry of Agriculture Feed Research Institute Chinese Academy of Agricultural Sciences Science of Animal and Technology College Anhui Agricultural University School of Life Sciences East China Normal University

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 he 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%, *** 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.

关键词： Nucleotides Growth performance Hybrid tilapia Intestinal microbiota Denaturing gradient gel electrophoresis

Cloning and expression of a novel chitinase gene from Citrobacter sp. P isolated from the intestine content of large yellow croakers and characterization of its protein product, an exo-chitinase with broad pH stability

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Cloning and expression of a novel chitinase gene from Citrob...

High-yield Production of a Chitinase from Aeromonas veronii B565 as a Potential Feed Supplement for Warm-water aquaculture

中国生物工程学会2014年学术年会暨全国生物技术大会

作者： Jie Xu Yalin Yang Yang Liu suxu he Li Xu Chao Ran Chunxiang Ai Zhigang Zhou College of Ocean & Earth Sciences Xiamen University Key Laboratory for Feed Biotechnology of the Ministry of Agriculture Feed Research Institute Chinese Academy of Agricultural Sciences

Chitinase plays an important role in the decomposition of chitin and potentially in the utilization of chitin as a renewable resource. In this research, we screened chitin-degrading bacteria from the intestinal samples of juvenile large yellow croaker fed with trash fish. A Citrobacter strain with chitin-degrading activity was isolated. The chitinase gene(chi-X) was cloned and expressed in Escherichia coli. The chitinase gene encodes a protein containing 493 amino acid residues. The nucleotide sequence of chi-X was deposited into the GenBank database under the accession number KC290945. Blast analysis showed that the deduced CHI-X sequence was most similar to the hypothetical protein of Citrobacter freundii(WP19078334.1), with 100% sequence identity. CHI-X has a glycoside hydrolase family-18 catalytic domain(Glyco8) containing the conserved DXDXE motif. Asp224, Glu226, and Tyr299 residues were predicted to be critical for catalytic activity for CHI-X by structure prediction. The maximum yield of CHI-X in Escherichia coli BL21(DE3) was 52.81% of total protein in the lysate supernatant. CHI-X was purified from the cell lysate by Ni2+-affinity chromatography. CHI-X may hydrolyze colloidal chitin(137.7 U/mg) and α-chitin from shrimp shells with similar activity. The Km and Vmax values of CHI-X toward colloidal chitin at pH 4.0 and 60°C are 6.24 mg/mL and 2.49 μmol/min,respectively. The optimal pH and temperature for CHI-X were 4.0 and 60°C, respectively. Excellent pH stability was observed for CHI-X, with around 90% of the activity maintained after incubation at pH from 3.0 to 11.0 for 1 hour. The enzymatic activity of CHI-X was stimulated by Mn2+, Li+, and K+, and inhibited strongly by Ag+, while proteases don’t inhibit its activity. The LC-ESI-MS analysis showed that CHI-X hydrolyzes colloidal chitin into GlcNAc and(GlcNAc)2, indicating it to be an exo-chitinase. Furthermore, an additive effect was observed between CHI-X and ChiB565 on colloidal chitin. CHI-X has good

关键词： Pseudosciaena crocea Citrobacter sp Chitinase

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High-yield Production of a Chitinase from Aeromonas veronii ...

芽孢杆菌R1共培养对嗜水气单胞菌NJ-1毒力基因表达的影响

中国生物工程学会2014年学术年会暨全国生物技术大会

作者： Yuting Zhang Zhigang Zhou Yuchun Liu Yanan Cao suxu he Fengmin Huo Chubin Qin Bin Yao Einar Ring

Chitin, present in crustacean shells, insects, and fungi, is the second most plentiful natural organic fiber after wood. To effectively use chitin in a cost-saving and environmentally friendly way in aquaculture, crustacean shells(e.g., shrimp-shell meal) are supplemented into aquafeed after degradation by chemical methods. herein, we describe a chitinase from Aeromonas veronii B565, designated Chi B565,, which potently degrades shrimp-shell chitin and resists proteolysis., We isolated recombinant ChiB565 of the expected molecular, mass in large yield from Pichia pastoris. ChiB565 is optimally, active at pH 5.0 and 50 °C and stable between pH 4.5 and, 9.0 at 50 °C and below. Compared with the commercial chitinase, C-6137, which cannot degrade shrimp-shell chitin, ChiB565, hydrolyzes shrimp-shell chitin in addition to colloidal chitin,, powdered chitin, and β-1,3-1,4-glucan. The optimal enzyme, concentration and reaction time for in vitro degradation of, 0.1 g of powdered shrimp shell are 30 U of ChiB565 and 3 h,, respectively. A synergistic protein-release effect occurred when, ChiB565 and trypsin were incubated in vitro with shrimp shells., Tilapia were fed an experimental diet containing 5 %(w/w), shrimp bran and 16.2 U/kg ChiB565, which significantly, improved growth and feed conversion compared with a control, diet lacking ChiB565. Dietary ChiB565 enhanced nitrogen, digestibility and downregulated intestinal IL-1β expression., The immunologically relevant protective effects of dietary, Chi B565 were also observed for 2 to 3 days following exposure, to pathogenic Aeromonas hydrophila.

关键词： Chitinase Aeromonas sp . Overexpression Feed supplements Aquaculture

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水产学报 2016年第3期40卷 299-307页

作者：何夙旭王全民黄路周志刚中国农业科学院饲料研究所农业部饲料生物技术重点开放实验室

为探讨芽孢杆菌潜在的淬灭靶点,本研究通过芽孢杆菌R1与嗜水气单胞菌NJ-1共培养,并对NJ-1生物量、信号分子产生量、毒力因子基因和群体感应（QS）关键调控基因表达量进行检测。结果显示:1NJ-1单独培养时,信号分子BHL和HHL的产量与NJ-1... 详细信息

为探讨芽孢杆菌潜在的淬灭靶点,本研究通过芽孢杆菌R1与嗜水气单胞菌NJ-1共培养,并对NJ-1生物量、信号分子产生量、毒力因子基因和群体感应（QS）关键调控基因表达量进行检测。结果显示:1NJ-1单独培养时,信号分子BHL和HHL的产量与NJ-1生长趋势一致,在27 h时达到峰值并启动Lux R表达,进而调控毒力因子金属蛋白酶、丝氨酸蛋白酶、肠毒素、气溶素和血溶素等表达,其在27;0 h时呈现峰值表达,通路Qse B在27;0 h启动表达,48 h时达到峰值,而种间调控Lux S基因表达一直处于低水平状态;2与芽孢杆菌R1共培养时,仅痕量AHLs信号分子被检出,毒力因子相关基因表达量均显著下调;Lux R表达受抑制,Lux S在36 h时表达量显著上调,未影响Qse B正常表达;3AHLs与R1共培养可被显著降解。研究表明,芽孢杆菌R1抑制NJ-1毒力因子相关基因表达可能与其对NJ-1多QS系统进行调控相关联。

关键词：嗜水气单胞菌芽孢杆菌群体感应毒力因子

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鸡胚给养调控鸡体健康研究进展

饲料工业 2023年第24期44卷 105-112页

作者：何夙旭吴子林刘强景胜凡张海军中国农业科学院饲料研究所北京100081 河北咏诺生物科技有限公司河北石家庄050200

随着无抗养殖和豆粕减量替代行动的不断推进,对肉鸡和蛋鸡的无抗和高效健康养殖方面提出了新的要求,尤其需要关注养殖过程中的健康问题。鸡胚给养技术可以通过人为的营养干预和调控在孵化期提高鸡的早期营养和免疫能力,并对鸡体的生长... 详细信息

随着无抗养殖和豆粕减量替代行动的不断推进,对肉鸡和蛋鸡的无抗和高效健康养殖方面提出了新的要求,尤其需要关注养殖过程中的健康问题。鸡胚给养技术可以通过人为的营养干预和调控在孵化期提高鸡的早期营养和免疫能力,并对鸡体的生长和健康产生长期和深远的影响。文章对近五年发表的关于鸡胚给养技术对鸡的器官发育、肠道菌群、抗逆性和抗病性等方面的作用进行了系统综述,旨在为鸡胚给养在禽类的健康养殖中的应用和研究提供理论依据。

关键词：鸡胚给养器官发育肠道菌群抗逆性

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嗜酸乳杆菌对斑马鱼子代幼鱼免疫功能的影响

动物医学进展 2013年第11期34卷 77-80页

作者：张羽盛洁李青余强邓扬卿素珠何夙旭西北农林科技大学动物医学院陕西杨凌712100 中国农业科学院饲料研究所北京100081

以嗜酸乳酸杆菌JCM 1132作为益生菌添加剂饲喂亲代斑马鱼,研究其对子代幼鱼免疫功能的影响。试验设对照组(饲喂基础饲料)和益生菌组(基础饲料中添加108 cfu/g嗜酸乳酸杆菌JCM 1132),饲喂30d后,对其孵化的幼鱼进行嗜水气单胞菌攻毒,分别... 详细信息

以嗜酸乳酸杆菌JCM 1132作为益生菌添加剂饲喂亲代斑马鱼,研究其对子代幼鱼免疫功能的影响。试验设对照组(饲喂基础饲料)和益生菌组(基础饲料中添加108 cfu/g嗜酸乳酸杆菌JCM 1132),饲喂30d后,对其孵化的幼鱼进行嗜水气单胞菌攻毒,分别检测攻毒后幼鱼死亡情况及攻毒期间鱼体内免疫因子il1b和nfkbiaa mRNA相对表达量。结果表明,在攻毒后5d到8d,益生菌组的幼鱼死亡率显著高于对照组(P<0.05);在攻毒后5h、24h和48h,益生菌组幼鱼的il1b和nfkbiaa转录显著低于对照组(P<0.05)。表明嗜酸乳酸杆菌饲喂斑马鱼亲鱼并不能提高子代斑马鱼的免疫功能。

关键词：益生菌嗜酸乳酸杆菌斑马鱼子代免疫

一株北方地区鲟鱼源病原细菌金黄杆菌B8致病性研究

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中国农业科技导报 2019年第4期21卷 96-103页

作者：何夙旭马国庆牛文静李由申周志刚中国农业科学院饲料研究所农业农村部饲料生物技术重点实验室北京100081 北京市水产科学研究所北京100125

从西伯利亚鲟(Acipenser baerii)病灶处筛选病原菌,结合药敏性试验、侵染路径及宿主相关指标分析,以期了解该病原菌的致病性。通过人工回归感染试验,从病鱼肾脏部位分离得到1株病原菌B8,对鲟鱼、罗非鱼和斑马鱼均有较强的致病性。经16S ... 详细信息

从西伯利亚鲟(Acipenser baerii)病灶处筛选病原菌,结合药敏性试验、侵染路径及宿主相关指标分析,以期了解该病原菌的致病性。通过人工回归感染试验,从病鱼肾脏部位分离得到1株病原菌B8,对鲟鱼、罗非鱼和斑马鱼均有较强的致病性。经16S rDNA序列分析鉴定为金黄杆菌,B8菌对庆大霉素和氯霉素等10种常用抗生素具有耐药性,对新霉素和红霉素敏感。侵染路径结果显示B8菌首先定殖在粘膜组织(鳃和肠),然后是淋巴组织(肝、脾和肾),各组织定殖菌量在48 hpi达到峰值,然后呈缓慢下降。肠道炎症因子IL-1β表达水平呈先上升(24 hpi为峰值)后下降趋势,在12～48 hpi间较未感染组差异显著(P<0.05),头肾溶菌酶和ROS活性表现出类似趋势(48 hpi为峰值),在感染的24～48 hpi间较未感染组差异显著(P<0.05)。首次报道了鲟鱼源致病株金黄杆菌,通过其致病性研究为西伯利亚鲟金黄杆菌引发的病害防控提供参考。

关键词：西伯利亚鲟金黄杆菌药敏性侵染路径

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藻类调控动物机体健康研究进展

中国饲料 2024年第17期 168-178页

作者：司丙文吴子林卢海凤童勤陈诺刘强何夙旭姚闽中国农业科学院饲料研究所北京100081 中国农业大学水利与土木工程学院北京100193 徐州爱乐佳生物科技有限公司江苏徐州221416 河北咏诺生物科技有限公司河北石家庄050200 青岛海兴源生物科技有限公司山东青岛266000

藻类作为古老的微生物之一,在自然界广泛存在。其富含多糖、蛋白质、脂肪酸等生物活性成分,具有抗炎、抗氧化、免疫调节等多种生物功能。因此,藻类添加在饲料中调控动物健康已成为热门的研究领域。本综述旨在总结藻类调控动物健康的研... 详细信息

藻类作为古老的微生物之一,在自然界广泛存在。其富含多糖、蛋白质、脂肪酸等生物活性成分,具有抗炎、抗氧化、免疫调节等多种生物功能。因此,藻类添加在饲料中调控动物健康已成为热门的研究领域。本综述旨在总结藻类调控动物健康的研究进展,深入探讨其生物活性成分及作用机制,并分析其在饲料领域的应用前景,以期为相关领域的研究者提供借鉴和参考,推动藻类饲料的应用和发展,为动物养殖业提供更高效、低成本的健康调控策略。

关键词：藻类饲料免疫调节动物健康

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不同类型犬粮营养品质的调查分析

现代畜牧兽医 2024年第10期 12-17页

作者：何夙旭黄春赵海明陈诺何昭明雒飞飞中国农业科学院饲料研究所北京100081 华谱科仪(北京)科技有限公司北京101407 上海伯纳天纯生物科技有限公司上海201100 徐州爱乐佳生物科技有限公司江苏徐州221400 北京农畔科技产业发展有限公司北京100080 青岛元信检测技术有限公司山东青岛266109

研究旨在评估4种不同类型犬粮的营养品质。试验选取市售的膨化粮(M)、鲜肉粮(F)、烘焙粮(B)和益生菌粮(P)等4种类型的犬粮各10份,检测其中重要营养成分蛋白质、氨基酸、钙、磷、维生素及塑化剂主要成分双酚A (BPA)的含量。结果显示:各... 详细信息

研究旨在评估4种不同类型犬粮的营养品质。试验选取市售的膨化粮(M)、鲜肉粮(F)、烘焙粮(B)和益生菌粮(P)等4种类型的犬粮各10份,检测其中重要营养成分蛋白质、氨基酸、钙、磷、维生素及塑化剂主要成分双酚A (BPA)的含量。结果显示:各组样品蛋白质含量为21.1%~40.4%,M组、F组、B组和P组的粗蛋白含量平均值分别为30.5%、30.5%、26.5%、30.7%,其中B组样品实测值与标定值存在较大差距。不同样品的氨基酸组成存在差异,个别样品中组氨酸和蛋氨酸+胱氨酸的含量未达到最低需求量。部分样品的VE含量未达标,尤其是P组VE含量未达标的样品较多。各组样品钙磷比在1.2~1.7范围内,符合犬类需求。所有样品中均检出了BPA,以B组含量较低。研究表明,大部分犬粮样品能够满足犬类营养需求,但个别样品在必需氨基酸和维生素方面仍存在提升空间。因此,未来强化监管和标准化管理犬粮至关重要,以确保犬营养需求。

关键词：犬粮氨基酸钙磷维生素营养品质