This study evaluated the effects of Lactobacillus plantarum LP37 and florfenicol (FF) on growth performance, immune response, and nutritional metabolism in Sebastes schlegelii. Four experimental groups of fish were established: a control group (CK, basal diet), LP37 group (basal diet + 10(9) CFU/g LP37), FF group (basal diet + 20 mg/kg FF), and FF-LP37 group (FF-supplemented diet for 15 days, followed by LP37-supplemented diet for 15 days). Serum, liver, and kidney samples were collected for biochemical and molecular analyses. The FF-LP37 group exhibited the highest weight gain and specific growth rates (SGRs) than those in the CK group (p < 0.05). Antioxidant indices showed that superoxide dismutase (SOD) activity was evaluated in LP37 and FF-LP37 groups; catalase (CAT) activity increased in FF group serum and FF-LP37 group liver (p < 0.05); total antioxidant capacity (T-AOC) was higher in all supplemented groups than in CK (p < 0.05); malondialdehyde (MDA) levels were elevated in the FF group (p < 0.05). Nutritional metabolism-related enzymes (hexokinase [HK], pyruvate kinase [PK], phosphoenolpyruvate carboxykinase [PEPCK], glutamine synthetase (GS), glucokinase, phosphoglucomutase, lipoprotein lipase [LPS], and fatty acid synthase [FAS]) were significantly altered, particularly in LP37 and FF-LP37 groups (p < 0.05). Molecular analysis revealed that expression of interleukin-1 receptor-associated kinase 4 (IRAK-4) and myeloid differentiation primary response 88 (MYD88) in the liver and kidney was upregulated in the FF group (p < 0.05), but downregulated in the LP37 and FF-LP37 groups compared with CK. In conclusion, dietary supplementation with LP37, FF, or the FF-LP37 sequence improved S. schlegelii growth, AOC, immunity, and nutritional metabolism, providing valuable insights for aquaculture dietary strategies.

Feeding frequency is a critical factor in Penaeus monodon aquaculture. This study aimed to investigate the effects of an intelligent high-frequency feeding strategy on the growth, intestinal microbiota, and metabolism of Penaeus monodon, a 35-day trial was conducted comparing a high-frequency (HF, 72 times/day) and a low-frequency (LF, 4 times/day) feeding regime using an intelligent feeding system. The physiological and mechanistic responses were assessed through 16S rDNA sequencing and metabolomics. The HF group demonstrated significantly superior growth performance, with markedly higher final body weight, length, WGR, AGR, and SGR, alongside a lower feed conversion ratio (FCR) than the LF group. Intestinal analysis revealed that the HF group possessed higher microbial diversity and a distinctly different community structure compared to the LF group. Beneficial families like Rhodobacteraceae and Lachnospiraceae were enriched in the HF group, whereas the LF group was dominated by Vibrionaceae. Metabolomic profiling showed that the HF group exhibited significant upregulation of key metabolites (e.g., L-alanine, citric acid) compared to the LF group, which were enriched in pathways central to amino acid metabolism and energy production. Correlation analysis further linked these shifts in beneficial microbiota with the altered metabolic profile. These comparative results demonstrate that high-frequency feeding reshapes the intestinal microbiome and host metabolism in P. monodon, providing a mechanistic explanation for its growth-promoting effects.

This study investigates Potentilla anserina L., a traditional medicinal plant in southwestern China, for its potential therapeutic effects on ulcerative colitis (UC). We developed a high-speed shear extraction method to isolate total flavonoids from its rhizomes, achieving a yield of 2.90 ± 0.07

This study investigated the impacts of white spot syndrome virus (WSSV) on the gut microbiota of Penaeus monodon through a comparative microbiota analysis of infected and healthy shrimp using 16S rDNA sequencing. The WSSV-infected shrimp exhibited characteristic white spots, reduced feeding activity, and behavioral lethargy preceding 100% mortality. The comparative microbiota analysis revealed a significantly diminished α-diversity in the infected specimens, marked by phylum-level dominance shifts from Proteobacteria (72.68%) and Firmicutes (11.27%) in the controls to Cyanobacteria (75.51%) and Proteobacteria (15.63%) in the WSSV-infected shrimp. An LEfSe analysis identified Arthrospira_PCC-7345 and Halochromatium as significantly enriched taxa during infection, contrasting with depleted populations of Ruegeria, Marivita, Bacillus, and seven other genera. The distinct dysbiosis pattern characterized by the pathogen-favored taxa proliferation and commensal species suppression demonstrates WSSV-associated microbiota restructuring, potentially contributing to disease progression in farmed P. monodon. These findings establish intestinal microbial biomarkers for early WSSV detection in aquaculture systems.

为探讨亚硝态氮(NO2-N)慢性胁迫对斑节对虾(Penaeus monodon)(非洲群体,以下称金刚虾)生理特性的影响,本实验以体质量为(6.06士0.76)g的金刚虾为研究对象,测定不同NO2-N浓度下金刚虾的行为、非特异性免疫以及消化功能.研究显示,NO2-N浓度≤6 mg/L时,金刚虾的活力、摄食不受影响;NO2-N浓度≥8 mg/L时,金刚虾摄食缓慢、游动异常、胃肠道模糊;NO2-N浓度为14 mg/L时,金刚虾开始死亡.金刚虾肝胰腺中脂肪酶(Lipase)、胰蛋白酶(Trypsin)活性在NO2-N浓度为6 mg/L时达到最大值,之后开始下降,当NO2-N浓度升至14 mg/L时活性最低,与对照组差异显著.NO2-N浓度由0上升至14 mg/L,血淋巴谷胱甘肽(GSH)含量、酸性磷酸酶(ACP)活性呈"先升高后下降"的趋势,谷草转氨酶(GOT)、谷丙转氨酶(GPT)的活性则呈"先升高后下降再升高"的趋势,NO2-N浓度为6 mg/L时,GHS、ACP活性达到最大值;NO2-N浓度为14 mg/L时,GOT、GPT活性达到最大值,与对照组差异显著.综合以上结果,工厂化养殖金刚虾时,建议将水体中NO2-N浓度控制在6 mg/L以下.

鲫(Carassius auratus)是鲤科(Cyprinidae)、鲫属(Carassius),为淡水性鱼类.1000多年前,鲫在中国被驯化,于16世纪引入日本,之后又被引入欧洲和世界大部分地区.除西部高原地区外,鲫广泛分布于我国各地[1].鲫肉质细嫩而鲜美,并且还具有健脾利湿、和中开胃、活血通络、温中下气的功效,对脾胃虚弱、水肿、溃疡、气管炎、哮喘、糖尿病有很好的滋补食疗作用[2].近年来,鲫养殖业发展十分迅速,由于养殖规模的不断扩大,加之养殖户对水质综合调控的重视程度不够,养殖环境条件日趋恶化,各种病害接踵而至,严重影响了鲫养殖产业的健康发展.

The development of microbial communities is important for the growth of the fat greenling Hexagrammos otakii; however, the relationship between microbial communities and fish diet is poorly understood. Here, we used metagenomics sequencing to investigate the gut microbiota of H. otakii at three key time points during development. The gut microbial diversity and community composition of H. otakii presented stage-specific signatures and appeared to shift with different diets and environmental conditions such as NH4 + -NO2- etc. Metagenomics analysis indicated that the dominant phyla were Proteobacteria and Firmicutes. With dietary changes from rotifers and Artemia to formulated feed, the dominant genera shifted from Vibrio and Photobacterium to Lactococcus, and variations in the gut microbiota increased with age. Based on metagenomics functional annotation using the Kyoto Encyclopedia of Genes and Genomes database, growth and diet at different stages affected the metabolic function of the gut microbiome by activating carbohydrate and amino acid metabolism while weakening lipid and nucleotide metabolism. In addition, as predicted by the Carbohydrate-Active enZymes database, glycoside hydrolase and glycosyl transferases may be involved in food degradation. Our results suggest that the H. otakii gut microbiota assembly was coupled to animal development and host age-associated biotic features and changes. Diet had a considerable effect on these distinct communities at different times, indicating that the fish gut microbiota rapidly adapted to dietary shifts. The microbiota therefore likely plays an indispensable role in nutrient turnover and fermentation. These findings can provide guidance for the development of probiotics and the application of feed additives.

[目的]解析斑节对虾(Penaeus monodon)(非洲群体)(俗称"金刚虾",以下同)携带耐药菌及耐药基因现状.[方法]本研究从山东滨州北海新区采集了金刚虾,对其肠道细菌常用抗生素的耐药菌性质及数量、占比及种类进行检测,通过荧光定量PCR技术分析肠道内容物样品中的4类抗生素的4种耐药性基因分布特征.[结果]肠道中可培养细菌总数约1.45×105-2.13×106 CFU/g,有四环素、萘啶酸、氟苯尼考、庆大霉素4种抗生素耐药菌的检出,其中喹诺酮类萘啶酸耐药菌占比最高,达到35.00％,氨基糖苷类庆大霉素占比最少.10种抗生素药敏性质分析表明,肠道可培养细菌对庆大霉素、氟苯尼考等6种抗生素高度敏感,对四环素、卡那霉素中度敏感,对萘啶酸、青霉素、阿莫西林耐药.从分离的耐药菌鉴定结果可以得出,可培养的抗生素耐药菌主要集中在弧菌属,基于属水平的不同抗生素耐药菌统计显示,不同抗生素耐药菌种类存在明显差异,且同一菌属有耐多种抗生素的情况.荧光定量PCR检测分析,4种耐药基因的丰度不同,tetA基因相对拷贝数和四环素耐药菌比例、floR基因和氟苯尼考耐药菌比例之间存在显著相关性(P＜0.01);qnrA基因相对拷贝数和萘啶酮酸耐药菌比例、aadA基因相对拷贝数和庆大霉素耐药菌比例之间均不存在显著相关性(P＞0.01).[结论]本研究说明,金刚虾肠道微生物中存在一定的耐药菌和耐药基因,具有携带风险.

本研究探讨饲料中添加地衣芽孢杆菌(Bacillus licheniformis)对大泷六线鱼(Hexagrammos otakii)生长、肠道消化酶、血清非特异性免疫及抗病力的影响.选取平均体重为(22.0±2.0)g的大泷六线鱼270尾,随机分成3组(对照组和2个不同菌剂水平的实验组),每组3个平行,每个平行30尾鱼.对照组投喂仅有蛋白液包裹的基础饲料,实验组投喂含活菌量达5× 107 CFU/g(0.5％)和1×108 CFU/g(1.0％)地衣芽孢杆菌的实验饲料.投喂50 d后进行致病菌杀鲑气单胞菌(Aeromonas salraonicida)攻毒感染,测定14 d内累积死亡率.结果 显示,实验组饲料中地衣芽孢杆菌可显著提高大泷六线鱼的特定生长率(SGR) (P＜0.05).与对照组比较,0.5％和1.0％地衣芽孢杆菌均可提高大泷六线鱼血清中SOD、CAT及T-AOC活性(P＜0.05),降低MDA含量(P＜0.05);GSH-Px活性在1.0％实验组较对照组下降,而0.5％实验组较对照组提高.地衣芽孢杆菌实验组鱼血清GS、MDH和HK活性均得到提高(P＜0.05),0.5％和1.0％不同剂量组的提高程度不同.地衣芽孢杆菌实验组鱼血清中AST和ALT活性较对照组均降低(P＜0.05),CHE和ADA活性较对照组有提高(P＜0.05).实验组鱼肠道胰蛋白酶、淀粉酶和脂肪酶活性均有不同程度的提高,且1.0％实验组活性最强(P＜0.05).攻毒实验结果显示,1.0％地衣芽孢杆菌组大泷六线鱼14 d内累积死亡率仅有35.55％ (P＜0.05).由此可见,饲料中添加地衣芽孢杆菌可促进大泷六线鱼生长,提高其肠道消化酶活性及非特异性免疫酶活性,增强其对杀鲑气单胞菌的抵抗能力.

This study evaluated the effect of probiotics (Clostridium butyricum, Bacillus coagulans) and Chinese herb polysaccharides (Astragalus polysaccharides, APS) on growth performance, immunity, disease resistance, and intestinal microbiota of rainbow trout (Oncorhynchus mykiss). Specimens of O. mykiss (n = 360; 79.9 +/- 2.2 g) were fed for 42 days with different diets containing a basal diet (control, C0), supplemented with 10(9) CFU/kg of C. butyricum + 10(9) CFU/kg of B. coagulans (E1) and 10(9) CFU/kg of C. butyricum + 10(9) CFU/kg of B. coagulans + 100 g/kg of APS (E2) as experimental diets. The results indicated that both E-1 and E-2 diets increased specific growth rate, reduced feed conversion ratio, and optimized muscle composition. Compared with the control treatment, after trout were fed with E-2 diet 42 days, activities of SOD, T-AOC, and CAT increased significantly, while malondialdehyde content decreased significantly in the E1 treatment. After Aeromonas salmonicida challenge, cumulative mortality was 80%, 41%, and 29% in C0, E1 and E-2 treatments, respectively. The abundance of Bacillales, Actinomycetales, and Pseudomonadales increased in the fish intestine of E-2 treatment, while that of Rhodobacterales and Rhizobiales decreased. These data showed that C. butyricum + B. coagulans with APS improved growth performance, enhanced immunity and disease resistance, and modulated intestinal microbiota of O. mykiss.

The gut microbiota composition of sea cucumber (Apostichopus japonicas) was investigated using high-throughput sequencing techniques. The mRNA expression of complement component 3 and lysozyme genes was evaluated using quantitative fluorescence PCR. Sea cucumbers were fed with a basal diet (control group) and an experimental diet supplemented with Codonopsis pilosula (experimental group) for 30 days. The results showed that the alpha diversity of the gut microbiota was changed in different indices, including Chao1, the abundance-based coverage estimator, the Shannon index, and Good's coverage. Dietary C. pilosula promoted the proliferation of the Flavobacteriaceae family of the Proteobacteria phylum and reduced the relative abundance of the Verrucomicrobiaceae family of the Verrucomicrobia phylum. We concluded that dietary C. pilosula supplementation could alter the network interactions among different microbial functional groups by changing the ecological network's microbial community composition and biological evolution. A positive effect on A. japonicus immune responses in the gut was seen via increasing the mRNA expression of the complement component 3 and lysozyme genes. It seems to happen via modulating the balance in gut microbiota.

The aim of this study was to evaluate effects of Bacillus licheniformis supplementation on growth, intestine digestive, antioxidant and metabolic capacity, intestine short-chain fatty acids content, and intestine microbiota composition of the Pacific white shrimp Litopenaeus vannamei. In total 2700 shrimp (initial weight 2.5 ± 0.1 g/shrimp) were randomly distributed into six tanks (450 shrimp/500-L tank) and fed at 28 ± 0.5 ℃ for 35 days (four times/day) with control diet and experimental diet supplemented with 108 CFU/g B. licheniformis, followed by an acute nitrite stress for 10 days. At the end of the feeding trial, shrimp dietary B. licheniformis showed improved weight gain, specific growth rate, survival rate after nitrite stress, and decreased feed conversion rate compared to control group. And acetic acid and butyric acid content in the intestine of shrimp dietary B. licheniformis increased significantly except for propionic acid content. In addition, activities of amylase, lipase, and trypsin and activities of glutamine synthetase, hexokinase, and malate dehydrogenase increased significantly compared to control group. After shrimp were exposed to nitrite stress for 10 days, glutathione peroxidase, peroxidase, total antioxidant capacity, and superoxide dismutase levels were still higher in dietary B. licheniformis-shrimp, which showed that B. licheniformis enhanced the resistance to environmental stressor such as nitrite from the level of immune. The 16S rRNA sequencing showed that B. licheniformis increased diversity and abundance of some bacteria. In particular, the abundance of Proteobacteria and Planctomycetes decreased, and the abundance of Firmicutes and Bacteroidetes increased. These results revealed that B. licheniformis could improve the growth performance, increased intestine short-chain fatty acids (SCFA) content, change intestine digestive and metabolic enzyme activity, and regulated microbiota composition, so enhance the intestine antioxidant ability of shrimp subjected to nitrite stress, which is beneficial for shrimp aquaculture.

从患病的鲤鱼体内分离出一株致病菌S-1,通过16S rRNA测序分析及系统进化树构建等综合鉴定该菌为维氏气单胞菌(Aeromonas veronii).序列分析结果显示,该菌株与维氏气单胞菌的亲缘关系最近,相似率达到99.8％.该菌株对氯霉素、庆大霉素、四环素、头孢氨苄、头孢哌酮、头孢曲松、头孢唑林、头孢他啶、头孢呋辛、米诺环素、氧氟沙星、哌拉西林、丁胺卡那、复方新诺明等抗生素高度敏感,对诺氟沙星、环丙沙星、羧苄西林、痢特灵、多粘菌素B、卡那霉素、苯唑西林、万古霉素、克林霉素、氨苄西林、青霉素等药物具有耐药性.该研究对防治由维氏气单胞菌引起的水产养殖动物疾病有积极意义.

目前北方高位池养殖模式正处于发展阶段,借鉴南方高位池养殖模式的建设,北方高位池主要采用覆膜高位池养殖模式,具有高产量、高投入、高收益的特点.介绍了北方高位池养殖模式的发展,分析了高位池养殖模式发展中存在的问题.最后,根据北方地区的实际情况,提出了3种创新健康生态高位池养殖模式.

青鱼在中国各地均有分布,随着养殖规模的扩大,养殖环境严重恶化、养殖模式和病害防控措施相对滞后等弊端日益突出,导致青鱼各类病害频繁暴发.其中细菌性病原对青鱼的危害最为严重,主要包括嗜水气单胞菌(Aeromonas hydrophila)和荧光假单胞菌(Pseudomonas fluorescens) (Wang H R et al, 2009;张波等,2010),容易引起鱼病急性暴发,造成青鱼大规模死亡.近年来研究发现,青鱼病原菌种类有增加的趋势,如叶键等(2016)在青鱼体内发现一种新发病病原类志贺邻单胞菌,引起青鱼暴发疾病. 2020年山东某青鱼养殖场暴发病情,病鱼行动缓慢、反应迟钝、停止摄食,解剖可见肠道充血、肾脏肿大.本研究从濒死的病鱼体内通过分离纯化获得一株优势菌株,并对该菌进行了鉴定、系统进化树分析和耐药性研究,旨在为生产中青鱼的疾病防治提供基础资料.

为研究中草药复方制剂对牙鲆Paralichthys olivaceus免疫力及抗病力的影响,实验基于中草药药物功效与配伍原则,研制出一种复方中草药免疫增强剂(YLK),配方包含黄芪、茯苓、党参、蒲公英、鱼腥草、白花蛇舌草、金银花、玉竹、甘草、五味子等;将复方中草药分别以1％(W:W)和3％(W:W)的添加量拌入基础配合饲料中,连续投喂牙鲆30 d,然后用迟钝爱德华氏菌Edwardsiella tarda攻毒,分别于攻毒后24 h和72 h取鱼血清进行免疫相关酶活性测定,同时在攻毒后6,12,24,48,72 h取鱼脾脏进行免疫相关基因表达水平的检测,并观察记录鱼体的累计死亡情况.结果表明,在迟钝爱德华氏菌感染后24 h和72 h,3％中草药添加组的牙鲆血清中碱性磷酸酶(Alkaline Phosphatase,ALP)、酸性磷酸酶(Acid Phosphatase,ACP)、超氧化物歧化酶(Superoxide Dismutase,SOD)以及溶菌酶(Lysozyme,LSZ)活性水平均显著高于仅投喂基础饲料的对照组;1％中草药添加组除ALP活性以外,其他3种酶活水平也显著高于对照组(P<0.05),2组不同中草药添加组鱼体血清酶活整体上差异不显著性;荧光定量PCR检测结果显示,各投喂组牙鲆脾脏组织中白介素1β(IL-1β)、白介素6(IL-6)、TCRα受体及C型溶菌酶基因表达量均出现不同程度的上调,而2个中草药投喂组牙鲆在感染后多个时间点的基因表达水平均高于单独投喂饲料组的牙鲆(P<0.05);添加3％中草药和1％中草药对牙鲆抗迟钝爱德华氏菌感染的相对保护率分别为34.2％和26.3％.研制的复方中草药制剂具有明显的免疫增强效果,能显著提高牙鲆抗迟钝爱德华氏菌感染能力,研究结果将为水产养殖中草药防病技术研究提供重要参考.

Aeromonas salmonicida subsp. masoucida (ASM) is an important bacterial pathogen of salmonid fish, which can cause huge economic losses to the fish farming industry. In order to screen effective vaccine candidate proteins, four outer membrane proteins of ASM, including OmpA, OmpC, OmpK and OmpW, were selected and recombinantly expressed in Escherichia coli. The result of western blotting showed that these four recombinant proteins could be recognized by rainbow trout anti-ASM antibodies. The immune protective effects of the four rOMPs were also investigated, and the relative percentage survival (RPS) of rOmpA, rOmpC, rOmpK and rOmpW were 71.1%, 81.6%, 55.3% and 42.1%, respectively. The RPS of rOmpC was significantly higher than the other three rOMPs, so the immune responses of rainbow trout induced by rOmpC were further investigated. The results showed that vaccination with rOmpC could significantly induced the production of specific serum antibodies and proliferation of sIg + lymphocytes in peripheral blood. Meanwhile, RT-qPCR analysis showed that rOmpC could significantly enhance the expression of the MHC-II, TCR, CD4, CD8, IL-8 and IgM genes compared with the BSA immunized group. These results demonstrated that rOmpC could induce strong humoral immune response in rainbow trout and provided effective immune protection against ASM challenge, which indicated that OmpC is a promising vaccine candidate against Aeromonas salmonicida infection.

为调查青岛即墨丁字湾潮间带菌种资源及优势度情况,采集丁字湾潮间带沉积物,利用平板划线法分离纯化细菌,根据生理生化实验和16S rRNA 基因序列分析对分离细菌进行菌种鉴定.结果表明:共分离到细菌66株,属于细菌域的2个大系统发育类群:变形菌门(Proteobacteria)和厚壁菌门(Firmicutes)中的2个科(Vibrionaceae和Bacillaceae))3个属(V ibrio 、Bacillus和Shew anella) .青岛即墨丁字湾潮间带内地衣芽孢杆菌(12 .12%) 、枯草芽孢杆菌(22 .73%)和蜡状芽孢杆菌(12 .12%)属于优势种,其他菌株均为常见种,芽孢杆菌属为优势属(74 .24%) .

本研究旨在比较分析益生菌制剂和抗生素对凡纳滨对虾(Litopenaeus vannamei)非特异性免疫及肠道微生物的影响.以初始平均体质量为(2.2±0.1)g的凡纳滨对虾为试验材料,随机分成3组,每组3个重复,每个重复100尾虾.对照组(C0)投喂基础饲料,试验组分别投喂添加0.5％益生菌制剂(El)和抗生素土霉素(E2)的试验饲料,通过生物化学、高通量测序方法检测对虾血清非特异性免疫功能及肠道微生物菌群结构变化.试验周期为14天.结果显示,益生菌制剂El组对虾血清酸性磷酸酶ACP、过氧化物酶POD活性显著提高(P ＜0.05),谷丙转氨酶GPT、谷草转氨酶GOT活性降低,而抗生素E2组效果反之;E2组土霉素对血清总抗氧化能力T-AOC活性产生显著增强作用,但效果短暂,随时间延长,活性发生骤降.El组益生菌制剂显著增强对虾肠道淀粉酶、脂肪酶、胰蛋白酶活性(P＜ 0.05),而E2组土霉素降低3种消化酶活性.E1组益生菌制剂可优化肠道微生物菌群结构,变形菌门Proteobacteria、放线菌门Actinobacteria、疣微菌门Verrucomicrobia 和Candidatus Saccharibacteria 丰度增加,E2组放线菌门Actinobacteria、Candidatus Saccharibacteria和拟杆菌门Bacteroidetes丰度稍有增加.0.5％益生菌制剂对凡纳滨对虾非特异性免疫功能及肠道微生物均产生了积极效应,且效果优于抗生素土霉素,适合作为免疫增强剂或饲料添加剂在凡纳滨对虾养殖中应用.