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71.
Commercial abalone growers and aquaculture researchers need to monitor and compare the growth rate of their stocks. Growth rates based on both length and weights are often calculated, but the process of disturbance for measurement will affect the results of most studies. In natural populations, constant (linear) growth in length has been supported, while logarithmic transformations for growth rates (length and weight) have been used for aquaculture studies. This study of growth of greenlip abalone (Haliotis laevigata, Leach) over a prolonged period (3 years) indicates that both data treatments are suitable. If weights are being used, then a growth model that allows for exponential growth, such as specific growth rate (SGR), must be used. If lengths are measured, then the calculation of simple differences in the lengths over time is sufficient. The apparent paradox in use of two forms of measure is comfortably rationalized as a result of the weight–length relationship and the von Bertalanffy relationship for this species. Thus, methods of minimal disturbance and stress, such as photographic estimation of length, could be used to accurately monitor growth trends in aquacultural studies as well as in industry.  相似文献   
72.
本文用高效液相色谱-串联质谱法测定鲍鱼中3-氨基-2-噁唑烷基酮(AOZ)、5-甲基吗啉-3-氨基-2-噁唑烷基酮(AMOZ)、氨基脲(SEM)、1-氨基-2-内酰脲(AHD)4种硝基呋喃类代谢物残留量的方法。0.2mol/L盐酸溶液水解鲍鱼组织中与蛋白结合的硝基呋喃类代谢物,用0.05mol/L的2-硝基苯甲醛溶液(2-NBA)37℃衍生16小时。用1.0mol/L磷酸氢二钾溶液调节pH至7.0~7.5,乙酸乙酯萃取。采用电喷雾电离,正离子扫描,选择反应监测模式(SRM)监测,内标法定量。本方法对4种硝基呋喃类代谢物标准曲线的线性回归系数均在0.99以上,线性范围为0.5μg/kg~20μg/kg。方法定量限为0.5μg/kg。在添加浓度0.5μg/kg~5μg/kg,回收率在75.2%~102.1%之间,相对标准偏差为3.56%~12.6%。说明本方法简单、灵敏,结果可靠,可满足实验室大量、快速分析的需求。  相似文献   
73.
This study developed a technique of sperm cryopreservation using liquid nitrogen (LN) vapour in farmed blacklip abalone Haliotis rubra through evaluating the following five key factors: (1) cryoprotectant agent (CPA) toxicity; (2) cooling temperature; (3) thawing temperature; (4) sperm to egg ratio and (5) sugar addition, using sperm motility or fertilization rate as quality assessment indicators. The results demonstrated that 6% dimethyl sulfoxide (DMSO) was the best single CPA for sperm cryopreservation in this species. The highest post‐thaw sperm motility was achieved when sperm were exposed to LN vapour for 10 min at 5.2 cm above the LN surface and thawed at 60°C and recovered at 16°C in seawater baths. Post‐thaw sperm motility was found to be significantly higher when 6% DMSO was used in combination with 1% or 2% glucose than 6% DMSO alone. Further evaluation of fertilization rate between these CPAs showed that 6% DMSO+2% glucose achieved the highest fertilization rate of 70% at a sperm to egg ratio of 10 000:1.  相似文献   
74.
综述了鲍幼虫变态及其分子机制的研究进展.鲍因其幼虫营卵黄营养,且同昆虫和蛙类相比,鲍幼虫变态速度快、存在提早发育(‘anticipatory’developmental program)现象,是研究贝类乃至海洋无脊椎动物变态现象的理想模式.早期研究采用药理学和电生理学方法发现了GABA等能够诱导鲍变态的物质,并且提出了变态过程信号通路,但调节幼虫变态的分子机制仍然所知甚少.研究人员采用差异显示PCR和基因芯片等手段获得了一些变态前后差异表达的基因.但是变态是由众多的基因和信号分子共同决定和影响的.传统获得差异基因的方法效率低、获得基因数量少、受公布的EST(表达序列标签)限制大,所以调控变态的分子网络和机制还尚未建立,缺乏对调控这一细胞过程的整体认识.转录组学分析获得大量变态差异基因,并且有助于建立差异基因相互作用网络,是研究变态分子机制的新方向.此外,变态差异基因的功能验证和注释是鲍变态分子机制研究的另一问题,基因干扰可能是解决方向之一.  相似文献   
75.
潮间带垒石蒙网养鲍技术研究   总被引:1,自引:0,他引:1  
1994年4月~1995年10月,在4个岩礁区共设置136个石垛,放养壳长1.3~3.0cm鲍苗55.1万只,进行潮间带垒石蒙网养鲍试验。对场址选择、放养密度、规格、投饵方法等进行了研究。结果:产商品鲍19.254t,平均亩产1397.8kg,平均壳长6.81cm,平均个体重39g,成活率89.6%,实现产值693.144万元、利润352.81万元。专家鉴定认为,养殖方式为国内首创,技术水平属世界先进。  相似文献   
76.
Substitution effect of Undaria pinnatifida with citrus peel by‐product (CPB) on growth, body composition and air exposure stressor of abalone was determined. A total of 1,080 abalone were distributed into 18 net cages. Five formulated diets were prepared in triplicate. The CPB0 diet contained 200 g/kg Upinnatifida. The 250, 500, 750 and 1,000 g/kg U. pinnatifida were substituted with the equal amount of CPB, referred to as the CPB250, CPB500, CPB750 and CPB1000 diets, respectively. Finally, dry U. pinnatifida was prepared. Abalone were fed for 16 weeks and then subjected to air exposure stressor for 24 hr. The cumulative mortality of abalone was monitored for the following 4 days after 24‐hr air exposure. Survival, weight gain and specific growth rate (SGR) of abalone fed all formulated diets were greater than those of abalone fed the U. pinnatifida. The greatest weight gain and SGR were achieved in abalone fed the CPB500 diet. The chemical composition of the soft body of abalone was not affected by the experimental diets. Higher cumulative mortality was observed in abalone fed the CPB0 and dry Upinnatifida at 16 hr after 24‐hr air exposure compared to abalone fed all other diets. In conclusion, U. pinnatifida could be completely substituted with CPB in abalone feed.  相似文献   
77.
ABSTRACT:   Amylase, with MW of 59 kDa, was purified from small abalone Haliotis sieboldii by ammonium sulfate fractionation, CM Sepharose Fast Flow and Sephacryl S-100 HR chromatographies. The optimal pH and temperature of purified amylase were 6.0 and 37°C, respectively. The purified enzyme was stable at pH 6.0–8.0 and low temperatures. It was activated by Ba2+, Mg2+, Ca2+, Co2+, Ni2+, Mn2+, K+, Ag+, Na+ and Li+, but completely or partially inhibited by Al3+, Cu2+, Cd2+, Hg2+ and Zn2+. EDTA could completely inhibit, while iodoacetamide, N-ethylmaleimide and urea partially inhibit the purified amylase. According to the digestion mode of various polysaccharides, the purified enzyme was considered to be an α-amylase.  相似文献   
78.
对杂色鲍(Haliotis diversicolor)分别按每kg体质量注射250mg、500mg和1000mg的L-精氨酸和5mg、10mg、20mg的环磷酰胺。每隔5d足部肌肉注射1次,共注射3次。第16天检测其血清中NO含量以及NOS活性的变化情况。同时采用注射环磷酰胺的方法(剂量为10mg/kg体质量),对杂色鲍血清中NOS活性进行负调控,分别在注射后3h、6h、12h、24h、48h、96h对血清NO水平和血清NOS、超氧化物歧化酶(SOD)、酸性磷酸酶(ACP)、碱性磷酸酶(AKP)以及溶菌酶(LZM)活性进行测定,并探讨它们之间的相关性。结果显示,注射500mg/kg的L-精氨酸可以显著提高实验鲍血清中NO水平和NOS活性,而注射10mg/kg的环磷酰胺则可以显著降低实验鲍血清中NO水平和NOS活性。血清中NOS活性与ACP、AKP以及LZM等活性的相关系数分别为0.8074、0.8292和0.7408,相关显著(P<0.05)或极显著(P<0.01),NO与SOD及LZM的相关系数分别为0.9302和0.9413,相关极显著(P<0.01)。实验结果为人工调控鲍体内的NO含量、增强其自身的非特异性免疫功能,从而提高鲍的抵抗疾病的能力提供了科学依据,同时也证明NO和NOS可以作为评价鲍免疫功能强弱的指标。  相似文献   
79.
蔡俊鹏  程璐  陈惠源 《水产科学》2006,25(9):480-482
鲍是珍贵的海产贝类之一,具有很高的营养价值。但近几年,我国台湾、福建、广东以及海南等省发生大规模九孔鲍苗掉板死亡的现象,很多鲍鱼场连续多月多批培苗,但或颗粒无收或每批次收获率极低,不到正常的10%。鲍苗掉板已是南方养鲍业中的一个非常普遍的问题,给我国南方各省鲍鱼养殖业带来极大的负面影响。  相似文献   
80.
The locations and effects of quantitative trait loci (QTL) were estimated for nine characters for growth‐related traits in the Pacific abalone (Haliotis discus hannai Ino) using a randomly amplified polymorphic DNA (RAPD), amplification fragment length polymorphism (AFLP) and SSR genetic linkage map. Twenty‐eight putatively significant QTLs (LOD>2.4) were detected for nine traits (shell length, shell width, total weight, shell weight, weight of soft part, muscle weight, gonad and digestive gland weight, mantle weight and gill weight). The percentage of phenotypic variation explained by a single QTL ranged from 8.0% to 35.9%. The significant correlations (P<0.001) were found among all the growth‐related traits, and Pearson's correlation coefficients were more than 0.81. For the female map, the QTL for growth were concentrated on groups 1 and 4 linkage maps. On the male map, the QTL that influenced growth‐related traits gathered on the groups 1 and 9 linkage maps. Genetic linkage map construction and QTL analysis for growth‐related traits are the basis for the marker‐assisted selection and will eventually improve production and quality of the Pacific abalone.  相似文献   
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