尿脱落细胞FISH单染色体拷贝大量异常分析

目的探讨尿脱落细胞FISH单染色体拷贝大量异常病例的FISH检测结果特点与最终活检病理结果的相关性,进一步完善FISH阳性诊断标准。方法收集847例行尿脱落细胞FISH检测,选择其中不符合阳性标准、但存在大量单染色体拷贝的5例作为研究对象,分析它们的临床特征、FISH检测结果特点、脱落细胞学特征和活检组织病理学检测结果。结果观察相应区域100个核异质上皮细胞,例1显示3号染色体3倍体扩增,异常细胞数32个;例2显示17号染色体3倍体扩增,异常细胞数48个;例3显示17号染色体5倍体扩增,异常细胞数56个;例4显示17号染色体单倍体,异常细胞数67个;例5显示p16基因杂合子缺失,异常细胞数61个,其它染色体均无异常。5例活检病理结果均为低级别或高级别乳头状尿路上皮癌。结论在临床实践中,尿脱落细胞FISH单染色体拷贝大量异常的病例应引起重视,将其归入可疑阳性比较合适,从而能提高尿FISH检测的敏感性,使患者获益。

核型分析联合其他遗传学检测技术在高龄孕妇产前诊断中的应用

目的探讨核型分析联合单核苷酸多态性微阵列技术(single nucleotide polymorphism array,SNP array)或荧光原位杂交技术(fluorescence in situ hybridization,FISH)或细菌人工染色体微珠标记技术(BACs on Beads,BoBs)在高龄孕妇产前诊断中的应用价值。方法回顾性研究因高龄行产前诊断的930例孕妇,全部行核型分析,联合BoBs检测420例,联合SNP array检测343例,联合FISH检测167例,分析其染色体结果及妊娠结局。结果930例胎儿中,核型异常192例(20.7%),三体综合征中以21-三体居多,性染色体异常中以克氏征居多。在核型联合其他检测中,联合SNP array检测可显著提高胎儿染色体异常检出率,差异有统计学意义(χ^(2)=6.191,P=0.013)。对于染色体嵌合体的诊断,核型联合FISH检测可更精准地确定嵌合类型及比例。孤立性高龄胎儿染色体异常风险相对较低,高龄合并无创高危胎儿染色体异常率最高,在高龄合并超声软指标中,随超声软指标数目增多,染色体异常率随之升高(P=0.001)。高龄孕妇年龄与核型异常、非整倍体尤其21三体的发生率呈正相关(P<0.05)。结论孤立性高龄孕妇胎儿染色体异常风险相对较低,高龄合并无创高危胎儿染色体异常的风险高,随超声软指标数目增多、孕妇年龄增长胎儿染色体异常的风险增加,核型联合FISH检测可更精准地确定嵌合类型及比例,核型分析联合其他检测尤其与SNP array技术可显著提高染色体异常检出率,有利于遗传咨询及再生育指导,是高龄孕妇首选的产前诊断方案。

伴ETV6-NTRK基因融合的肺非典型类癌1例并文献复习

目的探讨伴ETV6-NTRK基因融合的肺非典型类癌的临床病理学特征。方法回顾性分析1例肺非典型类癌的临床病理学特征,行支气管镜活检,采用免疫组化EnVision法检测蛋白表达,FISH、DNA和RNA二代测序法检测分子学改变,并复习相关文献。结果患者男性,49岁,影像学检查发现左下肺门占位伴肺门和纵隔淋巴结肿大,左侧肋骨病理性骨折。免疫表型:肿瘤细胞pan-TRK、CKpan、Syn、CgA、TTF-1和CK7均(+),SSTR2(个别+),CD56(+/-),Napsin A和p40均(-),Ki67增殖指数约15%;FISH检测ETV6基因和NTRK基因断裂重组;DNA二代测序检测发现IGR(UPSTREAM MCTP2)-ETV6融合,RNA二代测序检测到ETV6-NTRK3融合。NTRK靶向药物治疗后肿瘤明显缩小。结论NTRK基因融合可见于肺神经内分泌肿瘤;晚期肿瘤常规行NTRK免疫组化标记,可筛选NTRK基因改变靶向药物治疗获益的患者。

浅表性CD34阳性纤维母细胞肿瘤6例临床病理分析及文献复习

目的探讨浅表性CD34阳性纤维母细胞肿瘤(superficial CD34 positive fibroblastic tumors,SCPFT)的临床病理特点、免疫表型、诊断和鉴别诊断。方法回顾性分析6例SCPFT,行常规HE染色、免疫组化EliVision法染色。应用FISH法检测PRDM10基因断裂情况,并复习相关文献资料。结果6例SCPFT患者中,男性2例、女性4例。其中4例肿块位于下肢皮下,1例位于下腹部,另1例位于外阴。镜检:肿瘤细胞排列呈束状、实片状,细胞核明显多形性或畸形,核仁明显,可见核内假包涵体,胞质嗜酸性,部分区域细胞呈上皮样,未见核分裂象,间质散在少量炎细胞,免疫表型:肿瘤细胞弥漫强表达CD34和INI1,部分细胞表达CK(AE1/AE3),不表达SMA、CD68、desmin、S-100、CD31和ERG,Ki67增殖指数低于3%。FISH检测:4例SCPFT行FISH检测,其中3例PRDM10呈阳性。结论SCPFT是新近报道的一种软组织肿瘤,具有交界性或低度恶性生物学行为,诊断需与多种CD34阳性的软组织肿瘤相鉴别,避免过度诊断及治疗。

揭秘基因密码—荧光原位杂交分子病理报告解读

生命是一部由基因编写的复杂交响曲,而荧光原位杂交技术(fluorescence in situ hybridization,FISH)是揭示这部交响曲内在奥秘的重要工具之一。FISH是一种生物分子分析技术,用于研究细胞和组织中的染色体结构、基因定位和基因表达。该技术通过使用荧光标记的DNA或RNA探针与目标DNA或RNA序列杂交,然后通过荧光显微镜观察杂交信号的位置和数量。FISH技术让人们能够在细胞和组织层面上观察基因、染色体的情况,了解患者病变部位的分子生物学特征,从而为个体化医疗提供支持。但对于许多患者而言,他们并不了解FISH,甚至对为何进行FISH检测存在疑惑。本文将从科普角度解读FISH分子病理报告,以及FISH走入临床工作的意义。

Assessment of the Characteristics of Demersal Fish Communities Using Species-and Trait-Based Approaches in the Coastal Habitats Along Rongcheng Bay,Shandong Peninsula,China

Biodiversity declines have motivated many studies on the relationship between species diversity and ecosystem functioning.In this study,we described the spatial-temporal characteristics of demersal fish communities along a coastal habitat in Rongcheng Bay,Shandong Peninsula,China with both species-based and biological trait-based approaches.The field survey was carried out monthly using traps from April to October of 2018,and divided into three seasons(spring:April and May;summer:June,July and August;autumn:September,October and November).The study area included five distinct habitats:seagrass bed,natural rocky reef,bare sand,artificial reef together with natural rocky reef,and artificial reef together with bare sand.We analyzed the fish communities with three taxonomic diversity indices,including Shannon-Wiener,Simpson,and Pielou Evenness,as well as four functional diversity indices,including FRic,FEve,FDiv,and FDis,based on 7 functional groups which are categorized into 27 traits.The results showed that there were no significant differences in taxonomic diversity indices among different habitats in the three seasons.However,significant differences were found in the functional richness of fish communities among different habitats in three seasons.Seagrass bed represented the highest functional richness in spring and autumn.This study demonstrates that seagrass bed is very important in enhancing the functional diversity of fish communities in a complex habitat.The study also indicates that the combination of taxonomic diversity and functional diversity will provide a more detailed description of the characteristics of fish communities.

Debaryomyces hansenii supplementation in low fish meal diets promotes growth,modulates microbiota and enhances intestinal condition in juvenile marine fish

Background The development of a sustainable business model with social acceptance,makes necessary to develop new strategies to guarantee the growth,health,and well-being of farmed animals.Debaryomyces hansenii is a yeast species that can be used as a probiotic in aquaculture due to its capacity to i)promote cell proliferation and differen-tiation,ii)have immunostimulatory effects,iii)modulate gut microbiota,and/or iv)enhance the digestive function.To provide inside into the effects of D.hansenii on juveniles of gilthead seabream(Sparus aurata)condition,we inte-grated the evaluation of the main key performance indicators coupled with the integrative analysis of the intestine condition,through histological and microbiota state,and its transcriptomic profiling.Results After 70 days of a nutritional trial in which a diet with low levels of fishmeal(7%)was supplemented with 1.1%of D.hansenii(17.2×10^(5) CFU),an increase of ca.12%in somatic growth was observed together with an improve-ment in feed conversion in fish fed a yeast-supplemented diet.In terms of intestinal condition,this probiotic modu-lated gut microbiota without affecting the intestine cell organization,whereas an increase in the staining intensity of mucins rich in carboxylated and weakly sulphated glycoconjugates coupled with changes in the affinity for certain lectins were noted in goblet cells.Changes in microbiota were characterized by the reduction in abundance of several groups of Proteobacteria,especially those characterized as opportunistic groups.The microarrays-based transcrip-tomic analysis found 232 differential expressed genes in the anterior-mid intestine of S.aurata,that were mostly related to metabolic,antioxidant,immune,and symbiotic processes.Conclusions Dietary administration of D.hansenii enhanced somatic growth and improved feed efficiency param-eters,results that were coupled to an improvement of intestinal condition as histochemical and transcriptomic tools indicated.This probiotic yeast stimulated host-microbiota interactions without altering the intestinal cell organization nor generating dysbiosis,which demonstrated its safety as a feed additive.At the transcriptomic level,D.hansenii pro-moted metabolic pathways,mainly protein-related,sphingolipid,and thymidylate pathways,in addition to enhance antioxidant-related intestinal mechanisms,and to regulate sentinel immune processes,potentiating the defensive capacity meanwhile maintaining the homeostatic status of the intestine.

Exploring the effects of dietary inulin in rainbow trout fed a high‑starch,100%plant‑based diet

Background High dietary carbohydrates can spare protein in rainbow trout(Oncorhynchus mykiss)but may affect growth and health.Inulin,a prebiotic,could have nutritional and metabolic effects,along with anti-inflammatory properties in teleosts,improving growth and welfare.We tested this hypothesis in rainbow trout by feeding them a 100%plant-based diet,which is a viable alternative to fishmeal and fish oil in aquaculture feeds.In a two-factor design,we examined the impact of inulin(2%)as well as the variation in the carbohydrates(CHO)/plant protein ratio on rainbow trout.We assessed the influence of these factors on zootechnical parameters,plasma metabolites,gut microbiota,production of short-chain fatty acids and lactic acid,as well as the expression of free-fatty acid receptor genes in the mid-intestine,intermediary liver metabolism,and immune markers in a 12-week feeding trial.Results The use of 2%inulin did not significantly change the fish intestinal microbiota,but interestingly,the high CHO/protein ratio group showed a change in intestinal microbiota and in particular the beta diversity,with 21 bacterial genera affected,including Ralstonia,Bacillus,and 11 lactic-acid producing bacteria.There were higher levels of butyric,and valeric acid in groups fed with high CHO/protein diet but not with inulin.The high CHO/protein group showed a decrease in the expression of pro-inflammatory cytokines(il1b,il8,and tnfa)in liver and a lower expression of the genes coding for tight-junction proteins in mid-intestine(tjp1a and tjp3).However,the 2%inulin did not modify the expression of plasma immune markers.Finally,inulin induced a negative effect on rainbow trout growth performance irrespective of the dietary carbohydrates.Conclusions With a 100%plant-based diet,inclusion of high levels of carbohydrates could be a promising way for fish nutrition in aquaculture through a protein sparing effect whereas the supplementation of 2%inulin does not appear to improve the use of CHO when combined with a 100%plant-based diet.

比较两种固定液过度固定乳腺癌组织对FISH法检测HER2基因的影响

FISH技术常用于检测和定位染色体上特定的DNA序列[1],有利于病理鉴别诊断[2]、指导临床靶向用药[3]和监测肿瘤的复发[4]。组织标本的前处理对确保临床检验结果的准确性尤为重要,固定是组织处理中最重要的环节,也是整个制片过程中最无法补救的一步[5],组织过度固定或固定不足均会对检测结果造成影响[6]。乳腺癌穿刺样本,在离体后即加入固定液中保存,由于周末节假日等原因,部分样本未能及时送至病理科,穿刺组织体积较小易出现固定过度,在制片中常存在消化难和杂交背景亮等问题。

不同装载条件下小型渔船参数横摇的非定常RANS CFD仿真

Fishing boats have unique features that make them prone to changing loading conditions.When the boat leaves the port,the empty fish tank gradually fills up during fishing operations which may result in parametric roll(PR).This dangerous phenomenon that can lead to capsizing.The present study aims to understand better the behaviour of parametric roll in fishing boats and its relation to changing loading conditions.The study considers the effects of displacement and the GM/KM ratio on parametric roll,as well as the longitudinal flare distribution at the waterline.Two assessments to detect the parametric roll occurrence in early stage were carried out by using the level 1 assessment of parametric roll based on the Second Generation of Intact Stability criteria(SGIS)from International maritime Organisation(IMO)and the Susceptibility criteria of Parametric roll from the American Bureau of Shipping(ABS).Then,the CFD method is used to predict the amplitude of the parametric roll phenomenon.The results provide important insights to fishing vessel operators on how to manage loading conditions to maintain stability and avoid hazardous situations.By following the guidelines outlined in this study,fishing boats can operate more safely and efficiently,reducing the risk of accidents and improving the overall sustainability of the fishing industry.

Fish Gelatin-Based Film Containing Maillard Reaction Products:Properties and Its Use as Bag for Packing Chicken Skin Oil

Maillard reaction is a non-enzymatic browning reaction and its products(MRPs)have been proven to possess antioxidant properties.This research aimed to produce a fish gelatin-based packaging incorporated with MRPs to retard lipid oxidation in chicken skin oil(CSO)during storage at ambient temperature(28℃–30℃).MRPs produced from fish gelatin and fructose(1:1,90℃,pH 11)showed the highest antioxidant properties compared to those prepared under other conditions.Different glycerol/MRPs ratios(30:0,25:5,20:10,15:15,10:20,5:25,0:30)were incorporated into the film and resulting films were characterized.Glycerol/MRPs at 10:20 ratio was chosen to add into the film prior to bag preparation via heat sealing method.CSO packed in the bag was monitored for lipid hydrolysis and oxidation during 15 days of storage(30℃±0.5℃,RH 52%±5%).After 15 days,quality deterioration was lower in CSO packed in the prepared gelatin bag as evidenced by lower FFA,TBARS,and volatile compounds in comparison with CSO packed in LDPE bag.Fish gelatin film added with MRPs possessed an excellent water vapor barrier property(WV-BP).This finding indicated that MRPs could be used to substitute glycerol and simultaneously could serve as antioxidants for the developed active bag.The novel packaging can be a potential alternative packaging for retarding lipid oxidation of lipid or fatty foods.

产甲胎蛋白结直肠癌42例临床病理特征及预后分析

目的探讨产甲胎蛋白(Alpha-fetoprotein,AFP)结直肠癌的临床病理特征及预后。方法收集术前检测了血清AFP的结直肠癌手术标本2012例,筛选42例产AFP结直肠癌和同期性别、年龄、分期完全匹配的传统结直肠癌的临床病理资料。采用免疫组化EnVision法检测HER2、错配修复蛋白、p53、AFP、Glypican3、SALL4的表达,HER22+病例行FISH检测。可疑的壁外血管侵犯病例行弹力纤维染色。比较两组病例的临床病理特征和预后差异,将产AFP结直肠癌分为AFP高值组和AFP低值组,并比较两组临床病理特征和预后差异。结果产AFP结直肠癌占同期结直肠癌的2.1%(42/2012),产AFP结直肠癌和对照组的壁外血管侵犯率分别为35.7%、14.3%,中+高级别肿瘤出芽率分别为61.9%、40.5%,5年生存率分别为66.8%、85.1%,两组间差异有显著性(P<0.05)。AFP高值组肿瘤61.9%位于直肠,低值组23.8%位于直肠,两组间差异有显著性(P<0.05)。结论产AFP结直肠癌是一种少见类型的肠癌,肿瘤易出现壁外血管侵犯和中高级别肿瘤出芽,预后差。

Translocation of a fish spike from the pharynx to the thyroid gland:A case report

BACKGROUND A fish spike stuck in the throat is a common ear,nose,and throat(ENT)emergency.However,it is very rare for a fish spike to reach the thyroid tissue through the throat,which is very dangerous and can lead to pharyngeal fistula,cervical abscess,mediastinal abscess,and thyroid abscess.Proper and timely management can help reduce complications,especially in elderly patients.CASE SUMMARY In the case presented here,the causative factor was dentures,but improper management aggravated the condition.In the case presented here,an elderly woman with a history of accidentally swallowing fish bones for 20 d had a sensation of foreign bodies in her throat.Eventually,computed tomography(CT)of the neck showed that the left side of the thyroid gland had a dense shadow in the form of a stripe.CONCLUSION If a fishbone foreign body is not visible during endoscopic examination but the patient has significant symptoms,the surgeon should be aware that the fishbone may be lodged in the thyroid.To avoid a misdiagnosis,ultrasound,CT,and other tests can be used to clarify the diagnosis.T The first step in treating a fish bone in the thyroid gland is to determine the position of the foreign body and the extent of the infection,and to develop a personalized surgical plan for its removal.At the same time,scientific information should be made available to the general public so that people know that if a fish bone is accidentally lodged,they should not force it to be swallowed or be spit out by inducing vomiting,which are incorrect methods and may aggravate the condition or even cause it to migrate outside the cavity,leading to serious complications,as in this reported case.

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。

Performance Improvement of Kenaf/Glass Polymer Hybrid Composites by Effective Application of Fish Scale Powder as Filler:A Novel Approach

Modern technology for developing new items made from renewable resources is becoming more and more popular as a result of rising environmental concern.Recently,contemporary polymer composites have included the hybridization of natural fibers with synthetic ones,along with the inclusion of a variety of biowaste filler for developing sustainable goods.In this work,the kenaf/glass hybrid polyester composites are strengthened by the addition of fish scale(FS),which is taken from the fishs outermost layer of skin.Five different stacked-order laminates,such as KKKK,KGKG,GKKG,KGGK,and GGGG,are fabricated by using the hand lay-up method with four different weight concentrations of filler content:0%,5%,10%,and 15%.Mechanical possessions such as tensile,flexural,impact strength and micro-hardness have been evaluated through experimentation in accordance with ASTM standards.The experimental findings revealed that,the tensile strength and micro-hardness value of KGKG laminates with 15wt% of FS filler are found to be maximum of 118.72 MPa and 17.82 HV respectively which are 39.67%and 26.11%greater than that of KGKG laminates without FS filler.However,the flexural and impact strength of same laminates with 10 wt% FS filler exhibited a maximum value of 142.77 MPa and 62.08 kJ/m^(2).In order to corroborate its applicability for structural and building materials in open environment,the dimensional stability of the composite has been studied through moisture absorption test.The influences of FS filler loading on dimensional stability and resistance to moisture absorption capacity of laminates are also investigated.The experimental results reflected that the addition of FS-filler has significantly improved the dimensional stability of the laminates in moist environment by reducing the moisture absorption tendency.To further support the mode of failures,a fractography investigation of fractured surfaces was conducted.

高通量测序数据再分析在识别结直肠癌患者ERBB2扩增中的价值

目的评估未涵盖即ERBB2拷贝数变异(copynumbervariation,CNV)分析的高通量测序(highthroughput sequencing,HTS)数据再分析在识别结直肠癌患者ERBB2扩增中的价值。方法回顾性分析经病理活检确诊为结直肠癌并接受外周血cfDNA高通量测序样本的检测数据252例。根据经免疫组织化学(immunohistochemistry,IHC)和/或荧光原位杂交(fluorescence in situ hybridization,FISH)判断为ERBB2未扩增样本的HTS数据,计算17号染色体(Chr17)reads数占总reads数的比例范围,初步确定其为识别ERBB2扩增的阈值。根据初步阈值筛选可疑阳性样本,通过数字PCR、IHC和FISH进行验证。结果89例经IHC和/或FISH判定为ERBB2未扩增样本的Chr17 reads数与总reads数的比值为0.239±0.192(0.188~0.299)。以均数的1.25倍0.298作为识别ERBB2扩增的阈值分析其余163例样本数据,发现7例疑似阳性,比值为0.302~0.853。其中5例经IHC和/或FISH判定为阳性,6例经数字PCR验证为阳性,Chr17 reads与总reads数的比值与ERBB2/EIF2C1比值成正相关,相关性好(r2=0.909)。结论再分析未涵盖ERBB2 CNV分析的HTS数据可以初步识别结直肠癌患者的ERBB2扩增。

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.

Nitrogen and Phosphorus Removal from Lake Kinneret Inputs

The Hula Valley was drained in 1957. The land use was modified from natural wetland and old shallow lake ecosystems to agricultural development. About half of the drained land area was utilized for aquaculture. Population size was enhanced and the diary was developed intensively resulting in the enhancement of domestic and husbandry sewage production that increased as well. The natural intact Hula Valley-Lake Kinneret ecosystem was heavily anthropogenically interrupted: The Hula was drained and Kinneret became a national source for domestic water supply. Some aspects of the environmental and water quality protection policy of the system are presented. The causation and operational management implications for the reduction of Nitrogen and Phosphorus migration from the Hula Valley are discussed. Drastic (81%) restriction of aquaculture accompanied by sewage totally removed achieved a reasonable improvement in pollution control which was also supported by the Hula Project. The implications of anthropogenic intervention in the process of environmental management design are presented.

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.