黄鳝的年龄鉴定和生长

用黄鳝的耳石,脊椎骨和舌骨三种材料相对照,对其年龄进行了鉴定。认为舌骨是黄鳝年龄鉴定比较理想的材料,并首次提出尾舌骨也可以作为年龄鉴定的材料。分析了体长,体重的分布,分别用幂函数关系和直线回归方程计算体长与体重的关系式,并进行比较。     

南极鱼类年龄与生长研究进展

南极鱼类生长相对缓慢,独特的生物学特性使其年龄鉴定较其他海区鱼类更为困难。但考虑到鱼类年龄鉴定是开展渔业资源评估的基础,因此过去一些年来,硬质部位,如鳞片、鳍条(棘)、脊椎骨以及耳石等仍成为南极鱼类的主要鉴龄材料。本文对南极鱼类年龄鉴定的方法和材料进行了总结回顾,将年龄鉴定的方法和材料进行比较,分析各自优缺点。结果显示:(1)对于具鳞的南极鱼类,因鳞片在鱼类生长过程中存在重吸收现象,因而利用鳞片及鳍条(棘)单独鉴龄所得出的结果通常小于耳石的鉴龄结果,缺乏精确性;(2)南极鱼类生活跨度较大,高龄鱼体长频次分布严重重叠,以致无法准确判断其年龄结构;(3)耳石重量法易受到特殊个体影响而误判年龄;(4)因鳍条易损坏,脊椎骨采集较为困难,且许多南极鱼类无鳞,目前大多数南极鱼类使用耳石鉴定年龄,其也成为目前最为精准的南极鱼类鉴龄方法,但同时利用鳞片和耳石重量等对鉴定结果进行验证;(5)南极鱼类尚存在无统一的鉴龄标准、人为主观性较强以及缺乏早期生活史研究等不足之处;(6)为了研究南极鱼类早期生活史,耳石微化学及微结构等方法将被广泛利用。     

甲壳类同工酶研究进展

虾蟹类在分类学上属十足目(Decapoda)甲壳动物,在水产养殖业中占有重要的地位。20世纪60年代以来,随着众多经济虾蟹类(如罗氏沼虾、对虾、中华绒螯蟹)人工育苗的成功,使其养殖业发展迅猛,身价倍增。然而,当今的虾蟹养殖生产中还存在许多亟待解决的问题:首先,目前养殖的虾蟹     

鲨鱼类年龄和生长特性的研究进展

鲨鱼是海洋生态系统的重要生物类群。鲨鱼的年龄与生长作为基础的生活史特征,是资源评估所需的关键种群信息。鲨鱼的年龄与生长研究需要解决样本的选择与处理、年龄鉴定的方法和校正、生长模型的运用和参数估计等基本问题,否则难以得到可靠的结果。总结分析了两大类年龄鉴定方法及3种年龄校正技术的优缺点和应用局限性,比较分析了各种生长模型的应用差别,并对常见大洋性鲨鱼的生长参数进行了总结。研究认为,第一背鳍上部的脊椎骨是鲨鱼年龄鉴定的最佳硬质,硬质的处理需要借助化学方法,以提高轮纹清晰度;对年龄鉴定的校正是避免或减少系统误差的关键,校正方法的选择需要考虑鱼种的寿命;生长曲线的拟合需要选择多种备选模型,建议通过AIC信息准则筛选最优模型,为鲨鱼年龄与生长的进一步研究提供方法和技术上的参考,也可以为有关种类的资源评估提供生长参数。     

重金属对甲壳类毒理效应的研究进展

从重金属在甲壳类动物体内的毒性作用机制、富集规律及对机体生理代谢的影响等几个方面综合阐述了重金属对甲壳类毒性效应的研究进展,可为更深入地开展重金属对甲壳类的毒理学研究提供指导。     

新疆额尔齐斯河银鲫年龄鉴定比较与生长特征研究

以2013年4－10月从新疆额尔齐斯河采集的546尾银鲫（Carassius auratus gibelio）样本为材料,比较4种钙化组织（微耳石、鳞片、鳃盖骨和脊椎骨）年龄鉴定结果,选择最佳的年龄鉴定材料,研究其生长特征。结果表明,4种钙化组织中,微耳石磨片年龄读数的平均百分比误差（IAPE）最低（1.89%）,同一观察者2次读龄的吻合率最高（91.9%）,为4种材料中最为准确的年龄鉴定材料;采用微耳石进行年龄鉴定,银鲫样本由1～9龄组成,以3～4龄为主,占77.28%;银鲫体长与体重呈幂函数关系,雌雄群体间无显著性差异,体长与体重的关系为：W=2.661×10-5L3.085（R2=0.96,n=546）;生长规律用von Bertalanffy生长方程表示为：Lt=359.7 [1-e-0.172(t+1.066)], Wt=2042.3[1-e-0.172(t+1.066)]3.085;个体的生长拐点年龄为5.49龄,对应的体长及体重分别为243.2 mm和610.81 g。     

鱼类年龄鉴定研究概况

鱼类年龄鉴定是渔业资源评估的基础内容,经过长时间的发展,众多的方法被应用到这一领域。综述了目前应用较广泛的一些年龄鉴定方法,包括硬组织鉴定法和长度分析法两大部分方法,并分析了它们的优点和缺点。目前,鱼类年龄鉴定工作中存在的主要问题有:鉴定方法的精确度不高;鉴定方法多数较冗繁,耗时耗力;鱼类年龄鉴定未经标准化。有鉴于此,有必要对各种鉴定方法进行校验。介绍了几种常用的年龄校验方法,并对其进行了分析。     

甲壳类酪氨酸酶促褐变的研究进展

甲壳类的虾、蟹以其味美及营养价值高而深受人们喜爱.虾、蟹既是我国渔业经济中的重要产业,又是出口创汇的主要产品之一.近年来,我国虾、蟹养殖业发展迅猛,已经成为渔业经济发展的一大产业.2005年,我国甲壳类生产量达到3.2406×106 t,占水产品总产量的近10%,其中,海水养殖产量8.285×105 t,淡水养殖产量3.108×106 t.但是,由于虾、蟹在常温保存中容易褐变,生产者为延长货架期往往在加工中过量使用添加剂,从而导致二氧化硫超标的现象时有发生;此外,腌制梭子蟹在低温保存加工中也容易发生褐变.这些不仅严重影响产品本身的经济价值,而且亚硫酸盐等不适当的添加还给食品安全埋下了隐患.因此,深入开展虾蟹等甲壳类防褐变保鲜技术的研究显得尤为重要和迫切.     

利用耳石鉴定头足类年龄与生长研究进展

年龄和生长是头足类生物学研究的重点内容,利用耳石轮纹鉴定其年龄、分析其生长特性是一种可靠而有效的方法。耳石经提取、研磨、抛光后制备成切片,对切片观察面轮纹进行计数可得到日龄。研磨平面的选择是头足类耳石制片的最关键步骤,通常选择纵截面研磨。轮纹计数时,一般选择轮纹相对比较清晰的背区计数。适合头足类的生长模型有线性、指数、幂函数、逻辑斯谛、Gompertz和Von Bertalanffy等多种。分析认为,同一种头足类在不同生长阶段以及不同种群间,其年龄组成、生长率以及适合的生长模型往往不同,因此,建议应先对研究对象进行不同产卵季节或地理种群的划分,然后根据不同种群分别研究其生长并建立生长模型。     

Nutritional studies in crustaceans and the problems of applying research findings to practical farming systems1

Methodological approaches for undertaking research on the dietary nutrient requirements of farmed crustaceans should ensure that the studies are designed and conducted in such a manner that the ensuing results can be applied under practical farming conditions. Sadly, the majority of studies to date have had little practical applicability, the bulk of nutrient-requirement studies having been conducted under controlled, artificial, laboratory conditions. Despite the fact that the giant tiger prawn (Penaeus monodon Fabricius), the whiteleg shrimp (Penaeus vannamei Boone) and the fleshy prawn (Penaeus chinensis Osbeck) are the three most-cultivated crustacean species in the world (total aqua-culture production of these crustacean species in 1993 totalled 625487 metric tonnes or 66.9% of the total world farmed crustacean production), little or no information exists concerning their dietary nutrient requirements under practical semi-intensive pond-farming conditions (where the bulk of the production is currently realized). To a large extent this has been due to the apparent reluctance of the conventional laboratory-based crustacean nutritionist to also work under field conditions and the difficulty of quantifying the contribution of natural food organ-isms in the overall nutritional budget of pond-raised crustaceans. If meaningful conclusions are to be drawn from nutrient requirement studies and dietary feeding trials, it is essential that the experimental animals be reared under conditions mimicking as far as possible those of the intended farm production unit and environment, including holding facility (indoor or outdoor tank, cage or pond), feed preparation technique (grinding, pelleting, drying; diet texture, form, shape, size, buoyancy and water stability), feeding method (hand, demand or automatic feeding; feeding frequency and feeding rate–fixed or satiation feeding; day or night-time feeding), water quality (temperature, turbidity, salinity, oxygen and mineral concentration; water exchange rate, water circulation pattern and artificial aeration), photoperiod (artificial or natural) and crustacean stocking density. Finally, but not least, it is essential that the growth performance of the experimental animals be at least equal to or greater than that of the target crustacean species under practical farming conditions if realistic conclusions are to be drawn, and it is necessary that dietary nutrient requirements can be ascertained under conditions of maximum attainable growth.     

The reliability of whitefish (Coregonus lavaretus (L.)) age determination - differences between methods and between readers

Abstract— Age determinations of whitefish ( Coregonus lavaretus (L.)) were compared in two different tests. In the first test, the readers determined the age of each individual from one calcified structure (scale, otolith, or opercular bone) at a time. The samples from three populations, 50 specimens in each, were mixed so that the readers did not know which population each calcified structure was from. A sample of known-age whitefish was used in the second age determination test, where information such as time of catch, length, weight, and sex was available to the readers. In each of the 50 envelopes the reader got scale impressions and two otoliths, one of which had been burned and ground. In the first test, the precision of the readers was low both between readers and between different structures. In the samples of slow-growing populations, the determinations made from the otoliths showed older ages than the determinations from the scales. In the second age determination test the results were better; 73-90% (average 82%) of the determinations were correct. The use of two calcified structures and the knowledge of the material were considered to improve the accuracy. Age determination bias may occur that affects the age distribution: even though 80% of the fish were aged correctly, an exceptionally strong or weak year class could remain unidentified. The estimation of growth rate seemed less sensitive to incorrect age determination than age distribution.     

Bioactive roles of carotenoids and retinoids in crustaceans

Among the proposed functions of carotenoids in aquaculture have been those of pigmentation, antioxidant functions, as a source of pro-vitamin A, cellular protection from photodynamic damage, enhancement of growth and reproductive potential. However results reported by various authors are often contradictory. Some evidence suggests that these pigments may perform vital roles in growth and reproductive success in Crustaceans. Additional efforts need to be devoted to the understanding of the active forms of the carotenoid derived metabolites, retinoids in crustaceans. Dietary carotenoids are the sole biological precursors of retinoids in crustaceans. The importance of carotenoids as bioactive molecules reside to a large degree on their conversion to retinoids that are involved in the activation of hormonal nuclear receptors. Retinoids play a prominent role in many developmental processes, including embryonic development and differentiation of various cell types. The presence of receptors of retinoic acid in crustaceans and our findings of retinoids in the neuroendocrine complex and in reproductive tissue, as well as the enhancement of the ovarian development in shrimp suggests an important role of these metabolites in shrimp physiology for their successful aquaculture.     

两种培育方法对泥东风螺稚螺生长与存活的影响

本文报道了有底沙与无底沙培育方法对泥东风螺( Babylonia Lutosa)稚螺生长与存活影响的实验结果。以牡蛎为饵料,实验设计3×1042、5×104和7×104 ind/m2三个密度梯度,采用有底沙与无底沙两种方法培育刚变态的泥东风螺稚螺。经35 d培育,有底沙组稚螺壳高、体重的生长速度和存活率都高于无底沙组,壳高生长速度差异显著( P <0．05)。而两种培育方法不同的密度培育结果,密度7×104 ind/m2与3×104 ind/m2和5×104 ind/m2实验组稚螺壳高生长速度差异显著(P<0．05),而3×104 ind/m2与5×104 ind/m2实验组壳高生长速度差异不显著( P>0．05)。随着稚螺的生长其潜沙行为越明显,说明有沙培育更符合其具有的潜埋栖息习性,有利其生长和存活。     

粘菌素、杆菌肽及维吉尼霉素的检测方法研究进展

围绕水产品中粘菌素、杆菌肽及维吉尼霉素药物残留的检测问题,本文主要介绍了国内外动物源性食品和饲料中这3种药物残留的检测方法,分析比较了微生物法、酶联免疫分析法、毛细管电泳法、高效液相色谱法和液相色谱串联质谱法等几种检测方法的优缺点,认为HPLC法和Lc—MS法比较适合于水产品中这类药物残留的定量和确证检测。     

Experimental infection of European crustaceans with white spot syndrome virus (WSSV)

Eight European marine and freshwater crustaceans were experimentally infected with diluted shrimp haemolymph infected with white spot syndrome virus (WSSV). Clinical signs of infection and mortalities of the animals were routinely recorded. Diagnosis was by direct transmission electron microscopy (TEM), DNA hybridization (dot-blot and in situ hybridization) using WSSV probes and by PCR using WSSV specific primers. High mortality rates were noted between 7 to 21 days post-infection for Liocarcinus depurator , Liocarcinus puber , Cancer pagurus , Astacus leptodactylus , Orconectes limosus , Palaemon adspersus and Scyllarus arctus . Mortality reached 100%, 1 week post-infection in P. adspersus . When infection was successful, direct TEM observation of haemolymph revealed characteristic viral particles of WSSV, some observed as complete virions (enveloped), others as nucleocapsids associated with envelope debris. WSSV probes showed strong positive reactions in dot-blots and by in situ hybridization in sections and specific virus DNA fragments were amplified successfully with WSSV primers. White spot syndrome virus was pathogenic for the majority of the crustaceans tested. This underlines the epizootic potential of this virus in European crustaceans.     

Shell growth and age determination of the brackish water bivalve Corbicula japonica in Lake Shinji, Japan

ABSTRACT:   Shell growth and age determination of Corbicula japonica were investigated from samples collected monthly at two sites and field growth experiments from November 1999 to November 2000 in Lake Shinji. Both specimens did not grow in winter when the water temperature was below 11°C, but grew rapidly from spring to early summer when the water temperature rose from 15°C to 30°C, before further growing slowly from summer to autumn after the main breeding period. The monthly marginal growth distribution of the samples indicated that the concentric groove on the shell surface was an annual growth ring. It is concluded that the age of C .  japonica in the i -ring group when the shell growth resumed in spring was i  + 0.5 ( i  = 1, 2, · · ·), because the first true growth ring was formed at 0–2 mm in shell length, which then faded with growth. Lee's phenomenon was observed in the age determination results, and thus the growth coefficient and the asymptotic shell length of the von Bertalanffy growth equation were not estimated from the samples. However, these parameters were estimated from the annual shell length increments of the experimental individuals, which were 0.331/year and 28.2 mm, respectively.