上海市滩涂冬季底栖硅藻种类组成和生态分布

报道了上海市滩涂冬季底栖硅藻的种类组成、生态特征和数量分布情况。样品于2005年12月从7个站点中采集。经处理、镜检观察,从中鉴定出硅藻有90个分类单位,包括64种和22变种2变型(有两个未定种名),分别隶属于2纲6目9科27属。从水体咸度来看,淡水种类最多,为52个分类单位,占总数的57.78%;从温度性质来看,广温种占优势,有65个分类单位,占72.22%;从生活习性来看,底栖种占优势,有77个分类单位,占87.5%。数量分析表明,底栖硅藻细胞丰度变化为6.25×106~16.25×106cells/m2,平均为10.43×106cells/m2,在吴淞口站点含量最高。优势种为肘状针杆藻尖喙变种、斯氏布纹藻、膨胀桥弯藻和卵形双菱藻等,它们在各站点中都有分布,分别占总数的13.42%、12.56%、14.00%、9.88%。     

赤点石斑鱼与鞍带石斑鱼杂交子一代肌肉营养成分分析与评价

为分析赤点石斑鱼与鞍带石斑鱼杂交子一代的营养组成,参照国家标准,测定了体质量(182.84±29.35) g杂交石斑鱼肌肉的常规营养成分、氨基酸和脂肪酸组成,并对肌肉营养价值进行了评定。试验结果显示,杂交石斑鱼肌肉水分、粗蛋白、粗脂肪和灰分的含量分别为(74.07±0.71)%、(21.52±0.78)%、(4.03±0.15)%和(1.29±0.07)%。肌肉鲜样中测定了17种氨基酸,总量为(19.88±0.15)%;必需氨基酸和鲜味氨基酸总量分别为(8.64±0.13)%和(7.64±0.16)%,必需氨基酸指数为85.19,必需氨基酸组成符合联合国粮农组织/世界卫生组织标准。肌肉鲜样中含有17种脂肪酸,饱和脂肪酸、单不饱和脂肪酸和多不饱和脂肪酸分别占肌肉脂肪酸总量的(27.63±1.15)%、(22.75±1.22)%和(32.59±1.90)%,其中二十二碳六烯酸和二十碳五烯酸占肌肉脂肪酸总量的(19.27±1.27)%。研究表明,赤点石斑鱼与鞍带石斑鱼杂交子一代具有较高营养价值,可作为新品种进行开发。     

Effect of Dietary Antarctic Krill Meal on Growth Performance,Muscle Proximate Composition,and Antioxidative Capacity of Juvenile Spotted Halibut,Verasper variegatus

A 7‐wk feeding trial was conducted to evaluate the effects of dietary Antarctic krill meal (AKM) on the growth performance, proximate composition of muscles, and antioxidative capacity of juvenile spotted halibut. Six diets were formulated to contain about 50% protein and 8% lipid. A control diet (R0) without AKM and the other five diets with 8.1, 16.2, 24.3, 32.4, and 42.5% AKM supplementation (R10–50) to replace 10, 20, 30, 40, and 50% fishmeal protein were used to feed to juvenile spotted halibut. The juveniles were fed with each diet using three replicates and cultivated in the indoor culture system. Results showed that the specific growth rate, feed intake, and protein efficiency ratio in the R30 and R40 groups were significantly higher than that in other groups (P < 0.05). Survival rate in the R50 group was significantly lower compared with the R0 group and the other four AKM supplementation groups. Moreover, the rising AKM levels in diets had significant effects on the chemical composition of juvenile spotted halibut, showing significantly decreased contents of crude protein, but increased lipid and ash contents (P < 0.05). The total superoxide dismutase activity and catalase activity of serum and liver in AKM groups were significantly higher than those in the control group (P < 0.05). In contrast, the contents of malondialdehyde in serum and liver were significantly lower compared with the control group. These findings illustrate that a moderate AKM level in diets can significantly improve the growth performance, feed utilization, and antioxidative capacity in juvenile spotted halibut, which support the finding that AKM may be used as a good protein source for halibut in the aquafeed industry.     

东海和黄海南部七星底灯鱼摄食习性的研究

根据2008年5月至2009年2月东海和黄海南部4个航次大面调查所获得的七星底灯鱼(Benthosema pterotum)胃含物样本,对其食物组成、摄食强度、食物多样性程度及营养级进行了研究.结果表明,东海和黄海南部七星底灯鱼属浮游动物食性,桡足类是其最主要的食物类群,其％ IRI值、质量百分比和个数百分比分别为75...     

The changes in proximate compositions and glycogen contents in the dorsal ordinary muscles of the full-cycle cultured Pacific bluefin tuna Thunnus orientalis occurring with growth

ABSTRACT:   Using full-cycle cultured (FC) Pacific bluefin tuna (body length [BL], 42.6–66.4 cm; body weight [BW], 1.66–7.40 kg, n  = 15), the changes in chemical compositions and histological structure of the cephalal parts of the dorsal ordinary muscles (DOM) occurring with growth were investigated. A positive correlation ( r  = 0.9644, P  < 0.05) was observed between BL and BW with growth. The protein, lipid and ash contents of DOM and condition factor did not change with growth. However, the glycogen content of DOM increased ( P  < 0.05) from approximately 55 cm (BL) in this study. Using optical microscopic photographs, the various shapes of muscle fibers were observed and it was noted that the muscle fiber diameter increased ( P  < 0.05) with growth. Using transmission electron microscopic observation, many glycogen granules were observed in muscle fibers (especially, side of connective tissue) of DOM throughout the growth stage in this study. These results indicate that the glycogen content of DOM of FC Pacific bluefin tuna increases before the lipid with growth.     

Effects of alternative dietary lipid sources on growth performance,health status and fillet fatty acid composition of hybrid sturgeon (Acipenser baeri Brandt ♀ × Acipenser schrenckii Brandt ♂)

An 8‐week trial was conducted to determine the effects of total replacement of 12.9% fish oil (FO) with soybean oil (SBO), peanut oil (PNO), sunflower seed oil (SFSO), corn oil (CO) and canola oil (CNO) on growth performance, health status and fillet fatty acid composition of hybrid sturgeon (194.28 ± 0.14 g). Compared to the FO group, dietary SBO decreased growth performance (p < .05), increased serum glucose and hepatic lipid content (p < .05). No obvious adverse effects on growth performance and health status were observed in PNO, SFSO and CO groups (p > 0.05). The fish fed with CNO had increased growth performance (p < .05), reduced serum ALT, AST, LDL‐C (p < .05) and enhanced serum GSH‐Px, T‐AOC, and LZM, MPO, C4 (p < .05). The contents of C18:1n9, C18:2n6, and ∑n‐3 PUFA and ∑n‐6 PUFA in fillets showed a positive linear correlation with the diets (p < .05). In summary, PNO, SFSO and CO are probable alternative lipid sources to fully replace FO. Hybrid sturgeon prefers to use CNO as a lipid source with improved growth performance and health status. The fillet fatty acid composition mirrors the dietary fatty acid composition.     

福建海区浮游动物种类组成及数量分布特点

根据2003～2004年福建海区春季和夏季2个季度月浮游动物调查资料,分析和研究该调查海区浮游动物种类组成和数量分布特点。结果表明:浮游动物经鉴定共有226种,其中桡足类114种,占总种数的50.4%,以广盐高盐亚热带和热带种为主。浮游动物总生物量分布夏季比春季高,春季平均值为90.3mg·m-3,夏季为150.8mg·m-3,春季总生物量呈现由北向南递减,以闽东渔场最高,闽中渔期次之,闽南台湾浅滩渔场最低,密集区不明显,夏季则相反,随着暖流势力的增强,闽中、闽南台湾浅滩总生物量明显增加,以闽南台湾浅滩最高,且密集区明显;在调查海区总生物量起主导作用的优势种为普通波水蚤、锥形宽水蚤、微陀隆哲水蚤、亚强真哲水蚤,其密集区基本上是各种作业的主要渔场,与历史资料和邻近海域相比较,一直保持优势种地位有普通波水蚤、亚强真哲水蚤等,生物密集区基本相同。     

食糜在矛尾复鰕虎鱼消化道排空速度及其营养含量的变化

选择规格一致、健康无病、初始体质量(43.42±0.75)g的矛尾复鳙虎鱼240尾,随机分到20个水族箱内,每箱12尾.饱食量投喂鲜杂鱼.然后不同时间取样,测定胃、前肠、中肠、后肠内容物的质量及其粗蛋白、脂肪和水分含量,探讨食糜在矛尾复鰕虎鱼消化道排空速度及其营养含量的变化.试验结果表明,矛尾复鰕虎鱼在刚摄食后胃内容物达到最大值,并随着时间的延长减少,至22 h排空为0.线性回归模型能较好地用来模拟食糜在胃中的变化;食糜在前肠、中肠和后肠出现的时间分别为摄食后1、3 h和4 h.达到最大值的时间分别为摄食后12、9 h和10 h.试验结束时(投喂后26 h)前肠、中肠和后肠仍有剩余食糜.食糜中粗蛋白和脂肪含量在胃、前肠、中肠、后肠逐渐降低,但胃中粗脂肪含量高于食糜中的含量,而粗蛋白含量低于食糜中含量.     

16S rDNA克隆文库技术在活性污泥系统微生物组成分析中的应用

采用构建16S rDNA克隆文库方法对活性污泥系统的细菌种群多样性进行研究。随机测定了71个克隆子序列(1 500bp),BLAST比对结果表明,活性污泥中微生物群落具有高度多样性,可分为6个主要类群,其中,拟杆菌(Bacteroides)类群和γ变形菌(γ-Proteobacteria)类群在文库中所占比例最大,分别为38.03%和32.39%;其次是β-Proteobacteria,占19.72%;Firmicutes,Candidate division TM7和α-Pro-teobacteria类群所占比例相对较小,分别为4.23%,4.23%和1.04%。序列分析结果表明,活性污泥中具有可强化生物脱氮除磷效果的食酸菌(Acidovorax),包括假单胞菌(Pseudomonas),红环菌(Rhodocyclus)等细菌。     

中草药对斑节对虾生长、饲料利用和肌肉营养成分的影响

研究了中草药对斑节对虾Penaeusmonodon(初始体重0.30g.尾-1)生长性能、饲料利用以及肌肉营养成分和氨基酸的影响。6种实验饲料(按顺序分别为1,2,3,4,5和6)中中草药的添加量分别为0,0.5,1.0,2.0,4.0和8.0g·kg-1饲料。除了饲料2之外,斑节对虾的成活率、饲料系数和蛋白质效率都显著(P<0.05)优于对照组(饲料1)。投喂饲料3的斑节对虾增重率与对照组相比,虽然统计学上不存在显著差异,但有较大幅度的提高。投喂添加中草药的饲料对斑节对虾肌肉的水分和蛋白质含量无显著影响,但脂肪含量明显下降。结果表明,斑节对虾饲料中添加适量的中草药能够促进生长、显著提高成活率和降低饲料系数,并改变斑节对虾肌肉中脂肪含量和氨基酸组成。