有“fish”,而无“鱼”意

“fish”是“鱼”的意思，这是稍识英文的人都知道的。但并非含有“fish”的短语和句子都包含有“鱼”的意思。

IHC与FISH在乳腺癌HER2蛋白表达和基因扩增检测中的应用

目的比较免疫组织化学法(immunohistochemisity,IHC)和荧光原位杂交法(fluorescence in situ hybridization,FISH)在乳腺癌患者中检测人表皮生长因子受体2(human epidermal growth factor receptor 2,HER2)的应用。方法2019年2月至2022年1月本院收治158例乳腺癌患者作为研究对象,均采用IHC和FISH检测HER2的蛋白表达和基因扩增情况,比较两种方法的检测结果和一致性。结果IHC结果显示158例患者中HER2(1+)、HER2(2+)、HER2(3+)分别为5例(3.16%)、97例(61.39%)、56例(35.44%),FISH结果显示HER2扩增73例(46.20%),未扩增85例(53.80%),其中,HER2(1+)患者FISH均显示未扩增,阴性符合率为100%;HER2(3+)患者FISH均显示扩增,阳性符合率为100%;97例HER2(2+)患者FISH显示扩增17例,阳性符合率为17.52%。两种方法检测HER2一致性较好且具有统计学意义(Kappa值=0.775,P<0.05)。结论HIC与FISH在乳腺癌患者HER2表达检测中一致性较好,可在临床推广使用,必要时需结合两种方法检测。

IHC、FISH、qRT-PCR检测NSCLC ALK融合基因的对比分析

目的对比分析免疫组化(IHC)、荧光原位杂交(FISH)、实时荧光定量PCR(qRT-PCR)检测非小细胞肺癌(NSCLC)ALK融合基因情况。方法收集453例NSCLC标本。随机选取IHC检测的ALK融合基因不同表达程度标本40例[ALK(-)、(+)、(2+)、(3+)标本各10例],采用FISH和qRT-PCR法分别检测各组ALK融合基因表达水平,并进行一致性分析。结果IHC与FISH、qRT-PCR的ALK融合基因检测结果比较,IHC ALK(-)/(3+)与FISH、qRT-PCR检测结果一致率均为100%,具有高度一致性(r=0.781、r=0.740,P<0.05)。FISH与qRT-PCR的检测结果一致率为97.5%,具有高度一致性(r=0.943,P<0.05)。结论FISH、qRT-PCR法与IHC法检测在不同表达程度ALK融合基因样本中检测结果存在差别,IHC敏感性更高。FISH、qRT-PCR法在ALK融合基因样本的检测结果具有高度一致性。

Microbial Quality and Molecular Identification of Enterotoxigenic Staphylococcus Strains Isolated from Dried, Smoked, and Braised Fish Sold in Ouagadougou Markets

Background: The investigation of toxin genes in strains involved in staphylococcal food poisoning contributes to food safety. The aim of this study was to isolate and identify enterotoxigenic Staphylococcus strains from dried, smoked, and braised fish sold in Ouagadougou markets. Methodology: Staphylococci were isolated using standard microbiology methods. Staphylococcus strains were identified using API Staph kit (Reference # 20500, BioMerieux S.A., Marcy l'Etoile, France). The molecular identification of isolated Staphylococcus aureus strains was specifically confirmed by PCR using the Staur4 and Staur6 primers. The genes encoding enterotoxins, enterotoxin-like toxins, exfoliative toxins, and TSST-1 toxin were detected by multiplex PCR using specific primers from Inquaba Biotec West Africa Ltd, Africa's Genomics Company. Results: The results of the microbiological quality assessment indicated that most of the samples analyzed were found to be of unsatisfactory microbiological quality according to the Staphylococcus aureus microbiological criteria (m = 102). Overall, only 12.55% of samples were satisfactory, while 97.45% were unsatisfactory. The STAPH API gallery allowed the identification of the following species: Staphylococcus aureus, Staphylococcus xylosus, Staphylococcus lugdunensis, Staphylococcus hominis, Staphylococcus haemolyticus, Staphylococcus lentus, Staphylococcus sciuri and Staphylococcus capitis. Of the 108 Staphylococcus isolates, 81 (75%) showed at least one (1) toxin gene. Among the 21 toxin genes tested in this study, 20 genes were detected in all strains analyzed. The staphylococcal toxin genes detected were present in both Staphylococcus aureus and the other coagulase-negative strains isolated in this study. In addition, these genes are found individually or in association in certain strains. The most frequent genes detected in toxin gene-positive strains were: the tsst-1 gene in 45 isolated strains (41.7%), sei (16/14.8%), seg (13/12%), ser (7/6.5%) sec (6/5.5%), and sea (5/4.6%) for staphylococcal enterotoxins, seln (14/12.9%), selq (8/7.4%), for enterotoxin-like toxin gene and eta (3/2.7%) for exfoliative toxin genes. Conclusion: This study highlighted the pathogenicity of Staphylococcus strains isolated from dried, smoked, and braised fish sold in Ouagadougou markets. Monitoring toxin-producing strains of Staphylococcus is invaluable for better prevention of food poisoning.

Distribution and Contamination of Arsenic in Fish, Gastropods and Bivalves in the Aby and Tendo Lagoons in East of Ivory Coast

Lagoons are ecosystems for biodiversity and the livelihoods of coastal communities. The main objective of the study was to analyze the variability of arsenic concentrations in gastropods and bivalves in the Aby and Tendo lagoons, taking into account spatial, seasonal and hydrological variations. The study was carried out in four stages spread over two successive hydroclimatic cycles, including two seasons during the rainy season and two more during the dry season. The samples were taken in two areas of the Aby and Tendo lagoons. Arsenic levels were measured by ICP-MS. The results showed that mean arsenic concentrations in the muscles of organisms in Aby Lagoon ranged from 0.01 to 1.26 μg As/g, with a mean and median of 0.17 and 0.06 μg As/g, respectively. Fish had the highest levels of arsenic, followed by crustaceans, while molluscs and plants had lower and comparable concentrations of As. Arsenic concentrations in tilapia and jawbones varied significantly between sites and seasons, with higher concentrations at Tendo and during the rainy season. Arsenic concentrations in gastropods and bivalves were significantly higher than those of other species, with averages of 0.74 and 1.03 mg As/kg, respectively.

Evaluation of Agricultural Contamination Level by Heavy Metals and Pesticides in Sediments of Rivers and Water Bodies for Shrimp Fishing in the Lower Ouémé: Case of the Aguigadji, Ahlan and Sele Stations in Benin

This study assessed sediment contamination by heavy metals and pesticide active ingredients linked to chemical inputs used in agricultural activities in the lower Ouémé. Pesticide residues from the organochlorine, pyrethroid and organophosphorus families were investigated by gas chromatography, and heavy metals (Cd, Pb, As, Ni, Zn, Fe, Mg, Cr and Hg) by atomic absorption spectrophotometry. The metallic pollution indices, the contamination factor (CF) and the ecological risk index were calculated. The results revealed 8 active ingredients in the rainy season and 9 in the dry season. Glyphosate was the active ingredient with the highest concentration at all stations, 9.65 ± 0.84 mg/kg recorded in the dry season at the Aguigadji station. All glyphosate values were above the EQS. DDT, Atrazine and Endosulfan also showed high concentrations in the dry and rainy seasons. Emamectin, Abamectin and Lambda Cyhalothrin also showed high concentrations in the dry season at Aguigadji, Ahlan and Sele. Only glyphosate was recorded at the control station (Toho), but in very low concentrations. Lead showed the highest concentrations at all the stations, 265.96 ± 21.02 mg/Kg in the rainy season and 255.38 ± 79.09 mg/Kg in the dry season, all detected at the Aguigadji station and above the EQS. Zn, Ni, Fe, Cu and Cr were all representative in both the dry and rainy seasons at the contaminated stations. Manganese showed high concentrations in the rainy season. Pb showed very high contamination (FC ≥ 6) at the Aguigadji and Ahlan stations and significant contamination (3 ≤ FC 6) at the Sele station in both the rainy and dry seasons. Ni, Hg and Cd, showed either moderate or significant contamination at the contaminated stations. The risk values showed a considerable ecological Ri (190 ≤ Ri < 380) in the rainy season and a moderate ecological Ri (95 ≤ Ri < 190) in the dry season at these contaminated stations.

Effect of the Dietary Substitution of Fish Meal with Achatina fulica Meat Meal on the Growth Performance and Production Cost of African Catfish (Clarias gariepinus) Fingerlings

Fishmeal is the most preferred source of protein in aquafeeds, but it is expensive and scarce. Hence, Achatina fulica meat meal (AFM), which is much less preferred for human consumption out of three species of African giant land snails, was tested as a fishmeal substitute for Clarias gariepinus growth. Five iso-nitrogenous and iso-calorific diets were formulated, in which AFM substituted fish meal at 0% (control or Diet A), 25% (Diet B), 50% (Diet C), 75% (Diet D) and 100% (Diet E). These dietary treatments were each replicated thrice in a completely randomized design experiment, using 36-L plastic tanks in which the fish were fed daily rations corresponding to 5% of their body weight, for 8 weeks. Water quality parameters in the tanks were monitored. Proximate analyses were conducted on the fish meal, snail meal and experimental diets before the feeding trials. Cost-benefit analysis of the different diets was performed. The crude protein content of AFM (69.18%) was significantly higher than that of fish meal (55.81%). There was no significant difference (P > 0.05) in the mean weight gain, specific growth rate, feed conversion ratio, protein efficiency ratio and survival rate in fish fed Diet A and Diet B. The best protein efficiency ratio (0.77) was recorded in fish fed Diet B. Furthermore, the survival rate of fish increased with increased levels of AFM substitution. Water quality parameters were within a suitable range for tropical fish culture, indicating that the AFM did not pollute the water. The fish fed 25% AFM diet significantly (P Clarias gariepinus diets at a 25% substitution level. The aquaculture industry can thus exploit the availability of this feed resource.

Study of the Biological Quality of the Water in the Manantali Dam Reservoir: Analysis of the Fish Fauna and Plankton Communities

The aim of this study of the Manantali dam reservoir is to investigate the biological quality of the water through inventories and analysis of the ichthyofauna and planktonic communities (zooplankton and phytoplankton). Inventories of ichthyofauna and plankton communities were carried out quarterly from 2003 to 2022. The fish populations studied on the basis of bioindicators (species richness, diversity index, equitability index, diversification index) identified 29 species belonging to 10 families. The Cichlidae family is the most represented, while the Schilbeidae and Tetraodontioae families are less represented in terms of number of species. The species Hydrocynus forskalii and Brycinus nurse with relative abundances of 40.12% and 21.4% respectively, both from the family Alestidae, are the most abundant. The species H. forskalii has a frequency of occurrence of 100%. The specific diversity index of 2.9 and the equitability index of 0.6 show an average diversity of fish species. The diversification index of 2.9 indicates a theoretical number of habitats of 2 to 3. The planktonic community is made up of zooplankton and phytoplankton. The inventory of zooplankton shows the presence of 28 zooplankton species belonging to 9 families of the three zooplankton groups Rotifera, Cladocera and Copepoda. Analysis of the frequencies of occurrence of the various taxa showed that the characteristic species of Lake Manantali are the omnipresent rotifers Keratella cochlearis, Keratella quadrata and Trichocerca chattoni. For phytoplankton, the inventories carried out show the presence of 65 species belonging to 5 families (Chlorophycees, Diatomees, Dinophycees, Chrysophycees and Cyanophycees). An analysis of the frequency of occurrence of the various taxa shows that the characteristic species of Lake Manantali are Chlorophycees, with 7 species: Desmidium baileyi, Micrasterias alata, Sphaerocystis schroeteri, Spondylosium sp., Staurastrum heimii, Staurastrum subanchora, Staurodesmus wandae;Diatoms, with one species: Navicula sp. and Cyanophycees, with one species: Microcystis aeruginosa.

Oligo-FISH涂染揭示柚粗线期1号染色体的结构及配对

【目的】深化柑橘减数分裂粗线期染色体结构组成和配对分析。【方法】首次利用柑橘染色体全长特异寡核苷酸荧光原位杂交(oligo-fluorescence in situ hybridization,oligo-FISH)涂染探针,精准示踪鉴定沙田柚粗线期1号染色体的结构特征,比较其与有丝分裂间期细胞核、有丝分裂前中期和中期染色体的结构差异,并揭示粗线期全长染色体的同源配对。【结果】观测到同源配对的全长粗线期与有丝分裂中期较大染色质结构差异。经测定,柚粗线期1号染色体平均全长、长臂长、短臂长和臂比分别为中期的13.93倍、16.54倍、10.44倍和1.54倍,表现出更高FISH信号分辨率。检测到柚粗线期1号染色体着丝粒附近约3.01 Mb的探针信号缺失区。【结论】首次实现柑橘特定全长粗线期染色体的跟踪研究,为深入开展其结构和配对遗传利用的精准研究提供了新方法。

微滴式数字PCR与IHC联合FISH对乳腺癌新辅助化疗前后HER-2检测的分析

目的分析乳腺癌患者在新辅助化疗前后,采用微滴式数字PCR、IHC联合FISH检测人表皮生长因子受体2(epithelial growth factor receptor-2,HER-2)变化的价值。方法筛选96例乳腺癌患者均自2020年1月~2022年1月入院实施新辅助化疗,在化疗前后采用微滴式数字PCR(设为观察组)、IHC联合FISH法(设为对照组)检测HER-2变化,分析两种方案检测结果、与金标准符合率。结果化疗前,观察组检测显示阳性为46(47.92%)例,阴性为50(52.08%)例;对照组检测显示阳性为42(43.75%)例,阴性为54(56.25%)例,两组检测结果显示对比无明显差异(P>0.05),符合率为96.88%、98.96%;化疗后,观察组检测显示阳性为44(45.83%)例,阴性为52(54.17%)例;对照组检测显示阳性为40(41.67%)例,阴性为56(58.33%)例,两组检测结果显示对比无明显差异(P>0.05),符合率为98.96%、98.96%。结论将微滴式数字PCR与IHC联合FISH法应用在乳腺癌新辅助化疗前后HER-2检测过程中,两种方案与金标准符合率较高,可有效弥补常规检测不足之处,并为临床疾病的诊断提供丰富参考,值得借鉴。

Fish Canyon Tuff榍石He扩散及(U-Th)/He年代学研究

榍石富含U和Th,是(U-Th)/He定年的理想矿物之一。本文以Fish Canyon Tuff榍石为例,开展了榍石He扩散行为和榍石(U-Th)/He定年实验方法研究。榍石分步加热扩散实验结果表明He扩散系数ln(D/a2)与温度倒数呈负相关,与期望的热活化扩散过程一致。测试Fish Canyon Tuff榍石(U-Th)/He年龄分布在28.3~24.6 Ma之间,平均值为26.7±1.2 Ma(1σ),Th/U分布在4.6~5.5之间,平均值为5.2±0.2,在误差范围内与国际上已出版数据一致,表明建立的榍石(U-Th)/He定年实验方法可靠。本次测试15粒榍石碎片外表层(~20μm)存在不同程度的磨蚀(即不完整晶体),且榍石表层磨蚀厚度随着等效半径的增加而增大。榍石碎片(U-Th)/He年龄介于完整晶体(U-Th)/He年龄和真实(U-Th)/He年龄之间,且随着榍石等效半径及表层磨蚀厚度(<20μm)的增大,(U-Th)/He年龄更接近真实年龄,这表明榍石(U-Th)/He年龄不确定度与等效半径大小和表层磨蚀厚度有关。

基于FISH和SNP标记分析百农64对其衍生品种的遗传贡献

百农64因其抗病性好、适应性广,已成为黄淮南片麦区小麦育种的重要亲本之一。本研究将荧光原位杂交(FISH)和小麦55K SNP芯片分析相结合,对百农64及其衍生品种(百农207、百农160、华育198和04中36)和相关亲本共8份小麦材料进行全基因组分析,揭示百农64对其衍生后代的遗传贡献。结果表明,在研究材料中共鉴定出48种染色体多态类型(block),A、B和D基因组分别为18、20和10种,其中1A和6B染色体多态类型最多;在百农64和百农207中鉴定出了臂间倒位perInv6B,在5份小麦材料中鉴定到了小麦-黑麦T 1RS/1BL易位。利用55K SNP芯片在供试材料的A、B和D基因组分别获得8504、9726和5093个多态性SNP标记,多态信息含量(PIC)变异范围在0.110~0.375之间,平均值为0.295;百农64特异性SNP在衍生品种的A、B和D三个基因组上的分布比例分别为54.2%、46.9%和36.5%,6A染色体比例最高(85.4%),在百农207、华育198和04中36各染色体上分布比例的平均值均超过了50.0%。整合48个细胞学和23323个SNP标记分析显示,除百农160以外,其余3个衍生后代与百农64的遗传相似系数(GS)都超过了0.700;聚类分析结果显示百农64与其4个衍生品种聚为一类,与遗传相似系数结果一致。研究表明百农64对其衍生后代遗传贡献率较高,这为小麦种质资源利用和新品种选育过程中的亲本选配提供了理论支撑。

多发性骨髓瘤患者FISH检测结果与Durie-Salmon分期和R-ISS分期的相关性分析

目的探究多发性骨髓瘤(MM)患者原位荧光杂交技术(FISH)检测结果与Durie-Salmon分期(DS)和R-ISS分期的相关性。方法回顾性选取2020年1月至2022年2月河北北方学院附属第一医院90例MM患者作为研究对象,所有患者均行FISH检测,主要包括lq21扩增、l3q14缺失、IGH重排与P53缺失,并予以DS分期与R-ISS分期,记录患者的临床特征,分析FISH检测结果与DS分期和R-ISS分期的相关性。结果FISH检测结果显示,90例MM患者中lq21扩增阳性35例,l3q14缺失阳性27例,IGH重排阳性24例,P53缺失4例;lq21扩增阳性与阴性患者在DS分期、R-ISS分期方面差异有统计学意义(P<0.05);l3q14缺失阳性与阴性患者在DS分期、R-ISS分期方面差异有统计学意义(P<0.05);IGH重排阳性与阴性患者在DS分期、R-ISS分期方面差异有统计学意义(P<0.05);P53缺失阳性与阴性患者在DS分期、R-ISS分期方面差异无统计学意义(P>0.05)。经过Spearson相关性分析,结果显示lq21扩增、l3q14缺失、IGH重排与DS分期和R-ISS分期均呈明显正相关(P<0.05);P53缺失与DS分期和R-ISS分期无相关性(P>0.05)。结论MM患者多伴随FISH检测结果异常,表现为lq21扩增、l3q14缺失、IGH重排与P53缺失,其中lq21扩增、l3q14缺失、IGH重排与患者DS分期、R-ISS分期呈正相关,可将FISH检测与Durie-Salmon分期、R-ISS分期联合应用于MM预后评估。

Phenotypic and Molecular Characterization of Staphylococcaceae and Enterobacteriaceae Species Isolated from Smoked, Dried, and Braised Fish Marketed in Ouagadougou

Background: To preserve its nutritional properties, fish must have good sanitary quality. The objective of this study was to investigate some pathogens contaminating smoked, dried, and braised fish marketed in Ouagadougou. Methodology: Potential pathogens of Enterobacteriaceae and Staphylococcus were screened in eight (8) species of processed fish. The investigation of the germs was carried out following the normative methods of microbiology. The identities of the strains were determined by API 20 E (BioMerieux S.A., France) and API STAPH (BioMerieux S.A., France) kits for Enterobacteriaceae and Staphylococcus species respectively. The uidA gene profile in Escherichia coli isolates was determined by simplex PCR. The identity of Staphylococcus aureus was confirmed by amplification of specific 23S rDNA regions and nuc gene profile with PCR. Results: A total of 235 fish samples were analyzed. A diversity of Enterobacteriaceae and Staphylococcus was detected. Twenty species of Enterobacteriaceae were identified among which, the most frequent were Escherichia coli, Salmonella sp, Raoultella ornithinolytica and Serratia odorifera, respectively in 22.6%, 4.3%, 28.9%, 17.4% of the samples analyzed. However, eleven species of Staphylococcus were identified among which, Staphylococcus xylosus, Staphylococcus aureus, Staphylococcus lugdunensis, and Staphylococcus sciuri were the most frequent with respective percentages of 47.7%, 23.4%, 12.8% and 10.6% of samples. For all the samples, the species frequently isolated were: Raoultella ornithinolytica, Escherichia coli, Serratia odorifera, Staphylococcus aureus, Staphylococcus xylosus, and Staphylococcus lugdunensis. The uidA gene specific to Escherichia coli was detected in 82.85% of strains (29/35). Amplification of the specific 23S rDNA region using staur primers was observed in 98% (49/50) of the isolated Staphylococcus aureus strains and the nuc gene was detected in 86% of Staphylococcus aureus strains. Conclusion: The isolated bacteria are potential pathogens involved in foodborne illnesses and intoxications. Effective sanitary safety systems must be implemented to guarantee the sanitary quality of fish supplied to consumers.

预制烤鱼水分分布及关键挥发性风味物质分析

以即热型预制烤鱼为研究对象,采用低场-核磁共振技术(Low field-nuclear magnetic resonance,LF-NMR)、顶空固相微萃取与气相色谱质谱联用技术(Headspace-solid phase microextraction-gas chromatography mass spectrometry,HS-SPME-GC-MS)对不同电烤条件下烤鱼水分分布及挥发性风味物质进行研究。结果表明:250℃烤制20 min的烤鱼加工损失率最低,持水力最高。烤鱼中水分主要形式为不易流动水,200℃烤鱼的弛豫时间T22、T23最低,其次是250℃烤鱼,T2反演谱整体向左移动,说明水的自由度降低。250℃烤制20 min的烤鱼不易流动水峰面积占比(A22)最高,达94.03%,自由水峰面积占比(A23)最低,为1.93%,说明肌肉组织持水较优。在5组烤鱼中共鉴定出70种挥发性物质,主要为醛类、酮类、醇类及烃类等。通过相对气味活度值(Relative odor activity value,ROAV)筛选出关键挥发性风味物质分别为12、9、11、8和8种。5组样品贡献较大的风味物质为己醛、1-辛烯-3-醇、壬醛等,其中愈创木酚和4-甲基苯酚是碳烤烤鱼特有的关键风味物质。通过主成分分析,不同条件烤制的烤鱼关键挥发性风味物质差异明显。相关性分析表明,A22与异戊醛、庚醛和2,3-辛二酮呈显著正相关(P<0.05),与壬醛和愈创木酚呈显著负相关(P<0.05)。该研究结果为预制烤鱼开发提供参考。

耦合水文情势及鱼类繁殖的江垭水库生态调度需求研究

为了修复河流水文情势、维持河流生态系统健康,通过环境DNA采样、IHA水文指标变动分析和文献资料总结等方法,开展了江垭水库坝下水文情势及鱼类繁殖需求关系研究,提出了水库生态调度需求与建议。结果显示,2021年9月在溇水干支流综合调查获得鱼类55种,与20世纪90年代相比,流水性种类在干流江段显著减少了51.35%;按照生态调度优先等级评估原则,确定江垭水库生态调度的主要目标物种为产漂流性卵的银鲴(Xenocypris argentea)、银鮈(Squalidus argentatus)、贝氏䱗(Hemiculter bleekeri)和产粘沉性卵的鲤(Cyprinus carpio)、鲫(Carassius auratus);江垭建坝前后下游水文情势变化较大,发生高度改变且对鱼类洄游产卵及鱼卵发育有重要作用的水文指标包括年最大1日、3日平均流量指标、年出现高流量脉冲事件的次数和持续时间以及连续日流量上涨率。研究表明,以促进坝下不同产卵类型的鱼类繁殖为目标,生态调度需要一定的高流量脉冲次数和历时,还需要控制下游水位的日降幅,通过泄放合理的生态流量来维持下游鱼类的生物多样性。

抗菌肽对鱼类肠道菌群及免疫功能影响的研究进展

抗菌肽是先天免疫的组成部分,构成许多生物体抵御入侵病原体的第一道防线。抗菌肽是基因编码的(小于100个氨基酸),具有空间排列的疏水性和阳离子氨基酸特性的两性分子,具有多种生物学功能。抗菌肽(作为饲料添加剂)能够改善水产动物的生长性能,增强水产动物机体的抗病能力。鱼类肠道承担着营养物质消化吸收的功能,同时鱼类肠道内的微生物也参与机体的免疫反应。文章对抗菌肽的来源、分类、生物学功能、抗菌机制以及抗菌肽对鱼类肠道菌群和机体免疫功能的影响进行了系统的阐述,进而分析了抗菌肽、肠道菌群、机体免疫三者的关系。为抗菌肽替代抗生素在鱼类健康养殖中的应用提供了技术指导,为揭示抗菌肽在鱼体的相关作用机制奠定基础。

东山湾海马齿嫩茎和嫩叶的营养成分分析与评价

[目的]分析福建省东山湾鱼类网箱养殖区的海马齿(Sesuvium portulacastrum)可食用部位的营养成分与品质.[方法]采用国标法检测海马齿嫩茎、嫩叶和嫩茎叶的主要营养成分、维生素含量和氨基酸组成,采用氨基酸评分(AAS)、氨基酸比值系数分(SRCAA)和必需氨基酸指数(EAAI)进行氨基酸评价.[结果]海马齿嫩茎叶的水分、蛋白质、可溶性糖、粗灰分和粗纤维质量分数分别为90.87%,8.75%,3.29%,2.72%和1.18%,嫩茎的粗灰分和粗纤维质量分数显著高于嫩叶(P<0.05),而嫩叶的水分和蛋白质质量分数显著高于嫩茎(P<0.05).海马齿嫩茎叶的维生素A、维生素B_(2)、维生素C和β-胡萝卜素质量分数分别为0.028,0.049,10.992和1.090 mg/100 g,其在嫩叶中的质量分数分别是嫩茎中的3.27,2.31,2.05和7.14倍.海马齿嫩茎和嫩叶均能测出17种氨基酸,以谷氨酸质量分数最高,而胱氨酸质量分数最低;嫩茎叶的总氨基酸质量分数为1.241%,必需氨基酸、药用氨基酸和甜味氨基酸分别占氨基酸总质量的35%,63%和31%;除脯氨酸、胱氨酸和甲硫氨酸外,嫩叶的14种氨基酸质量分数均显著高于嫩茎(P<0.05).氨基酸评价结果显示,海马齿各部位氨基酸种类齐全,比例分配良好,蛋白质营养价值高,嫩茎的SRCAA和EAAI均高于嫩叶.[结论]经比较,海马齿的营养价值不亚于商业化海水蔬菜北美海蓬子(Salicornia bigelovii)以及福建省常见食用海藻兼鲍饵料如龙须菜(Gracilaria lemaneiformis)和海带(Laminaria japonica),其含有更多的蛋白质和粗纤维,且SRCAA和EAAI评分更高,可为海马齿作为新型海水蔬菜、鲍饵料开发利用以及“鱼菜共生”养殖模式的推广提供参考.

益生菌对幼鱼生长发育的影响及调控机制

近年来,高密度、集约化的水产养殖模式导致养殖鱼类疾病频发,其中幼鱼发病率和死亡率的上升严重影响水产养殖业的健康快速发展。如何保障幼鱼的健康是当前水产养殖业亟需解决的问题。益生菌能够通过多种方式提高幼鱼的抗病力、增强幼鱼对营养素的摄取、促进幼鱼的生长发育。已有大量的研究阐述了益生菌在幼鱼生长发育及免疫调节中的作用,但相关机制还需深入探究。本文综述了近年来益生菌在幼鱼生长发育及抗病方面发挥的有益作用及其可能的机制,讨论了益生菌在幼鱼养殖应用时可能存在的问题以及发展方向,为益生菌在水产动物幼体养殖中的应用提供了理论参考。

鱼类产卵敏感期河流生态流速的分区分类阈值研究

敏感生态流量目标的合理制定是生态流量管理的重难点问题。针对目前敏感生态流量目标制定中存在的计算方法繁杂、关键参数缺乏等问题,本文以鱼类产卵期为重点,提出了分区分类河流敏感期生态流速和生态流量核算方法,制定了不同区域(东北、黄淮海、西南、长江中下游和东南沿海)、不同类型(按集水面积、山区河段和平原河段等划分)河流敏感期生态流速阈值。结果显示,全部分区分类推荐流速平均值为0.66 m/s,其中山区大站平均值为0.94 m/s、山区小站平均值为0.62 m/s、平原大站平均值为0.63 m/s、平原小站平均值为0.46 m/s。基于阈值核算了全国217个鱼类产卵生境保护河段的敏感期生态流量目标,并结合部分断面湿周法结果对阈值合理性与适应性进行了验证,验证结果表明相关阈值和方法适应于不同类型、不同规模河流,可为我国现阶段河流敏感生态流量管控提供参考。