浅谈围塘文蛤养殖的几个问题

文蛤，属于软体动物门、瓣鳃纲、真瓣鳃目、帘蛤科。贝壳近于心脏形，表面平滑。文蛤多分布在较平坦的砂质海滩中。幼贝多分布于高潮区下部，成贝分布于中潮区下部、至低潮线以下水深５－６米处。文蛤为广温性半咸水贝类，最适水温在１５－２５℃，适应海水比重在１．０１４０－１．０２４０，地理分布较广。文蛤具有随着生长由中潮区向低潮区下带移动的习性，俗称“跑流”。 文蛤为高经济价值贝类，我县规模开发也只有近两年。１９９９年４月份引进北方文蛤７２００公斤，规格为１６０颗／公斤，分别放入５口海水围塘（总面积为１５．３公…     

文蛤增养殖技术讲座

1暂养区文给大批死亡的情况我国南方地区文蛤出口主要集中在10月至翌年5月。这一期间温度偏低，尤其是冬季气温可达到零度以下，潮间带分布的文蛤在寒冷的冬季潜居深，采捕相当困难，生产单位和经营部门一般在高温期将商品文蛤收购来集中暂养，需要时可以在短期内捕得一定数量的文蛤，按期完成出口任务。商品文蛤暂养期间一个突出的问题，就是常发生文蛤的突然大批死亡。暂养场文蛤大批死亡季节往往发生在9～10月份，而春、冬两季一般无这种突然大批死亡现象。但在冬天，大风浪后，文蛤被打出滩面，积聚成堆在围网四周，又未及时疏散，也会…     

浅海筏式吊养文蛤初步试验

文蛤具有迁移习性，滩涂围栏养殖管理不便。为此，进行了筏式吊养初步试验。5月开始投放壳长2．5—3．0cm文蛤苗种2500kg，至10月10日收获壳长4cm以上文蛤7200kg，平均每笼纯收人17．6元，文蛤长势良好。对影响存活率的因素以及放养密度、苗种选择进行了探讨。     

文蛤养殖技术讲座 第一讲 文蛤生物学特性及增养殖概况

文蛤（Meretrixmeretrix）是我国沿海常见的一种重要经济贝类，肉质细嫩、味道鲜美、营养丰富、创汇率高。养殖文蛤具有投入少、见效快、收益大、技术管理方便等优点，已成为我国沿海渔区加速实现农村小康和现代化进程一项支柱产业。1文蛤的生物学特性1．1文蛤的形态特征文蛤属软体动物门，真瓣腮纲，帝蛤科，文蛤属的一种双壳贝类。贝壳背线呈三角形，腹缘呈圆形，两壳大小相等。贝壳表面膨胀，光滑，被有一层黄褐色光滑似漆的壳皮，壳面花纹随个体差异甚大，小形个体，贝壳花纹细致、清晰、典雅，花样多端，大型个体则较为恒定，通常在贝…     

黄河三角洲地区文蛤底播增殖研究

<正>历史上黄河三角洲海域盛产文蛤。海洋渔业系统1984年5-10月调查显示潮间带文蛤平均生物量为41.23克/米2,1988年7-9月调查显示文蛤的平均生物量为94.57克/米2。但自上世纪90年代以后由于酷捕乱采以及黄河断流的影响,黄河三角洲海域文蛤的生物量急剧下降,至2008年滩涂资源调查时,5月份     

更正

文蛤是我国沿海分布较广的海产经济贝类。贝壳略呈三角形，表面膨胀，光滑，被有一层黄褐色光滑表皮，大多栖息在河口附近含沙量60-80％的平坦滩涂上。适宜文蛤生活的海水比重约为1．010～1.020之间，比重低文蛤生长缓慢，比重超过1．020以上就会发生死亡。文蛤对温度的适应性较广，水温在30℃以下均能良好生长。     

文蛤人工育苗技术探讨

文蛤是我国重要的养殖贝类,广泛分布在我国的各个海区。文蛤为蛤中精品,享有"天下第一鲜"的盛名。文蛤的贝壳在药典上称蛤壳,可做药材治病。几年来,由于市场的     

不同花纹文蛤杂交育种初步研究

挑选不同花纹并且性腺成熟较好的文蛤亲贝进行阴干刺激,在水温约30 ℃,海水相对密度1.016～1.018,pH 7.9～8.1的条件下采用升温刺激、异性产物等诱导方法促使其产卵排精.共育出2组文蛤苗种.亲贝于2004年6月30日(即自交组)排放的精卵经过受精后,受精卵在底面积为0.1 m2、体积为60 L的水桶中,经过孵化、附着变态等生长发育过程, 至9月6日, 共得到平均壳长2.18 mm,壳高1.87 mm的稚贝8703个,共15.57 g;经过室内培养至12月8日,测量得到壳长8.32 mm, 壳高7.03 mm的幼贝1843个,共150 g.至2005年6月28日,得到壳长19.22 mm,壳高16.39 mm文蛤2.5 kg.亲贝于7月9日(即杂交组)排放的精卵受精后,经孵化、附着变态等生长发育过程,至9月6日,共得到平均壳长4.19 mm,壳高3.71 mm的稚贝12721个,共102.50 g.至12月8日,测量得到壳长15.32 mm,壳高12.93 mm的幼贝4999个,共4000 g.2005年6月28日,称量得到壳长28.06 mm,壳高22.73 mm文蛤30 kg.在文蛤幼虫培育及稚贝培育过程中,观察了文蛤稚贝生长状况及贝壳花纹的形成变化过程.试验中发现文蛤稚贝生长状况较好,并且稚贝在生长发育过程中贝壳出现不同形状的花纹.     

紫菜丝状体的病害防治

紫菜丝状体的生长基质是各种贝壳，但以文蛤壳较好。贝壳使用前应洗刷干净，剔去残留的闭壳肌，以免影响水质。 丝状体常见病可以分为３类：一类是由病菌引起的传染性病害，如黄斑病、泥红病；一类是培养条件不适造成的病害，不具传染性，如乙型泥红病；再是丝状体贝壳在培养过     

文蛤粪卟啉原Ⅲ氧化酶基因克隆及与壳色性状的相关性分析

粪卟啉原Ⅲ氧化酶(coproporphyrinogen-III oxidase,CPOX)是卟啉类化合物合成过程中的关键酶,而卟啉是形成机体色素的重要化合物。采用RACE方法克隆获得文蛤粪卟啉原Ⅲ氧化酶基因(MmCPOX)的cDNA序列,该序列全长1490 bp,其中开放阅读框1173 bp,编码390个氨基酸,预测分子量为12.04 ku,理论等电点为5.05;预测该酶含有跨膜结构域和Coprogen-oxidas结构域;从构建的系统进化树来看,软体动物门的文蛤、加州海兔和太平洋牡蛎首先聚在一起,显示出较近的亲缘关系。qRT-PCR结果显示,MmCPOX基因在文蛤早期发育的各个时期均有表达,但在D形幼虫期以后表达量显著升高;在文蛤成贝的7个组织中,外套膜和血液中表达量显著高于其他组织,表明其与血卟啉合成和壳色卟啉形成相关;在不同壳色文蛤中,红壳文蛤、暗纹文蛤、细纹文蛤的外套膜中表达量显著高于黑斑文蛤和白壳文蛤,表明其参与形成红色和褐色壳色。     

胶州湾移植底播菲律宾蛤仔的生长和死亡特性

2004年5月至2005年4月对胶州湾菲律宾蛤仔（Rudimpes philippinarum）底播增殖区进行了逐月定点采样，将样品带回放于实验室内水族箱暂养，每站随机取样，共对3269个个体进行了基本生物学特性测定，研究了移植底播菲律宾蛤仔的生长、死亡等渔业生物学特性。结果表明，底播增殖菲律宾蛤仔苗种的平均个体质量0．26g、平均壳长11．1mm；底播蛤仔与野生蛤仔在生长规律上基本一致，春末至秋初（4～9月）是其主要生长期；1～3龄期间个体生长速度较快，1～2龄、2～3龄，个体质量分别增长3．88g和4．02g；1～2龄生物量增长最快，2～3龄由于死亡率增大，其生物量增长缓慢；1～3龄蛤仔软体部的生长速度快于贝壳，5～6月是菲律宾蛤仔的繁殖肥育期。根据个体生长特性，3龄为最佳采捕年龄；根据目前的养殖状况，2龄蛤仔已达到商品规格，从生物量上分析，采捕2龄蛤仔收益最高；6月是最佳的捕获时期。蛤仔生长具有明显的季节变化，水温是影响菲律宾蛤仔生长的主要环境因子。[中国水产科学，2006，13（4）：642—649]     

砂海螂底播增养殖的研究↑（*）

在烟台北部沿海进行了砂海螂底播增养殖技术研究,选择风浪小、流速不大于０．１ｍ／ｓ的砂泥底质内湾海区。底播前应松动底表层,清除敌害。１０～１１月播放壳长１２ｃｍ的贝苗。经约３年的生长,平均壳长达７．３ｃｍ,平均个体重５０ｇ,存活率达１５％以上。     

Size-based physical properties of hard-shell clam (Mercenaria mercenaria) shell relevant to the design of mechanical processing equipment

The knowledge of physical properties of food products is of fundamental importance for efficient design, dimensioning, manufacturing and operation of different mechanical equipment used in the processing of these products. Clams of different sizes are utilized during processing, thus, all the sizes must be given adequate consideration for efficient processing. This study was conducted to investigate the size-based physical properties of hard-shell clam (Mercenaria mercenaria) shell relevant to the design of mechanical processing equipment. The sizes of the clam shells were identified and categorized as small, medium and large; and its effect on the physical properties were studied. The parameters investigated were length, width, thickness, arithmetic and geometric diameters, surface area, sphericity, aspect ratio, moisture content, bulk and true densities, porosity, clam shell weight, coefficient of static friction and angle of repose. Increase in the length and width of clam shells increased the arithmetic and geometric diameters, and the surface area, but decreased the sphericity and aspect ratio. Moisture content, bulk and true densities, porosity and clam shell weight increased with increase clam shell size. Coefficient of static friction of clam shell was highest on rubber surface and lowest on glass surface, and was positively correlated with size; while angle of repose decreased with size. There was an excellent agreement between the prediction of the normal distribution and the actual distribution of the clam shell sizes. All the parameters were significantly different with respect to clam shell size at p < 0.05, which makes a strong case for the consideration of clam shell size during processing.     

浙江沿海彩虹明樱蛤生物学特性初步研究

通过对浙江沿海4个海区彩虹明樱蛤的壳长、壳宽、软体质量、鲜出肉率、肥满度、蛋白质和脂肪含量等在一年生长最快的季节(5—9月)变化趋势的研究,进一步证明了壳长与壳宽、壳长与软体质量均呈线性正相关,慈溪的彩虹明樱蛤的鲜出肉率、肥满度、蛋白质含量都是最高的。如果以出肉量为标准,7月是最佳的采捕季节。乐清的彩虹明樱蛤脂肪含量最高可作种贝。     

Light and electron microscopic studies of Eperythrozoon suis]

A light and electron microscopic study was carried out on pigs experimentally infected with Eperythrozoon (E.) suis during the acute and chronic phase of infection. During the acute phase Eperythrozoon organisms can be recognised by light microscopy as bright to dark orange points or circles. In contrast, in the chronically infected pigs E. suis appear as bright yellow or green small dots on the edge of the erythrocytes or in the plasma. By scanning electron microscopy, immature, juvenile and mature forms of E. suis could be seen on the same erythrocyte during the acute phase. In chronically infected pigs ring-shaped, rounded resting-stage forms, measuring about 1 micron in diameter, can be observed.     

EFFECT OF LIGHT INTENSITY AND MALE AND FEMALE EYESTALK ABLATION ON REPRODUCTION OF Penaeus stylirostris AND P. vannamei

This 97-day study, conducted during midwinter using a recirculating water system, was designed to evaluate the effect of light intensity and male and female eyestalk ablation on reproduction of P. vannamei and P. stylirostris. Four light intensities were established using various levels of fluorescent lighting (bright, 14.7 μEm^-2s^-1; moderate, 4.4 μEm^-2s^-1; dim, 0.6 μEm^-2s^-1; and dark, 0.0 μEm^-2s^-1) and the fifth consisted of artificial lighting supplemented with natural light through a translucent skylight (skylight, 4.7–9.3 μEm^-2s^-1). Unilateral eyestalk ablation was performed on all male P. vannamei in one of each pair of tanks within a treatment. In addition, half of the females in each tank were unilaterally ablated. Ovarian maturation, spawning, molting rate, and survival were monitored daily within each tank. Growth and gonad development were measured at termination. The optimum light intensity for P. stylirostris appeared to be lower than that for P. vannamei. P. stylirostris matured and spawned more frequently in the skylight and dim treatments than in the moderate, dark, and bright treatments. P. vannamei matured and spawned more frequently in the skylight, bright, and moderate treatments than in the dim and dark treatments. Natural light supplementation beneficially affected reproduction of both species. Male eyestalk ablation increased gonad size and doubled mating frequency of P. vannamei in comparison to unablated controls. This is the first documentation of increased penaeid shrimp reproduction by unilateral eyestalk ablation of males. Even more significant may be recognition that male gonadal development is a limiting factor in reproduction of shrimp in captivity.     

波纹巴非蛤的性腺发育和生殖周期

根据波纹巴非蛤生殖细胞发育的规律和它们在滤泡中所占的比例,把波纹巴非蛤生殖腺发育过程分为增殖期、生长期、成熟期、排放期和休止期五个阶段。根据相对重量、鲜出肉率、干出肉率等指标的变化,并结合性腺的组织切片确定,波纹巴非蛤的性腺发育在闽南海区一年—个周期。繁殖期在5月中旬——10月下旬,但其繁殖高峰则有两次,分别在5月下旬和10月上旬。这表明波纹巴非蛤的成熟期和生殖期是相互重叠的。此外还观察到该种有雌雄同体现象。     

文蛤红色选育系幼贝滤水率响应面法分析

为比较文蛤红壳色选育系与江苏野生群体在不同条件下滤水率的差异并找出文蛤最佳滤水率条件,采用了试验生态学方法和响应面法对文蛤红壳色选育系幼贝进行滤水率的研究。试验结果显示,在一定范围内,文蛤幼贝滤水率随盐度、温度和藻类密度的增加而增大,超过一定范围,幼贝滤水率随盐度、温度和藻类密度的增加而减小;在同等条件下,文蛤红壳色选育系幼贝与野生群体滤水率无显著差异,但文蛤红壳色选育系生长速率显著高于野生群体;通过响应面法优化,文蛤红壳色选育系幼贝的最佳滤水率条件为:盐度21.82、温度27.40℃、藻类密度9.96×10^4个/mL,此条件下滤水率的预测值为1.62 mL/(个·min)。     

SEM observations on larval shell morphology of Manila clam Ruditapes philippinarum and their utility

Manila clam Ruditapes philippinarum is common and abundant on Japanese tidal flats, forming a commercially important clam fishery. However, annual catches of Manila clam have decreased drastically since 1975?C1985. To study larval recruitment processes of Manila clam, we carried out scanning electron microscopy (SEM) observations on larval and juvenile shells of clams reared at 20 and 24?°C. There was no significant difference in final shell length of trochophores between 20 and 24?°C. However, the larval duration was much longer and the shell length of settled size of pediveligers was much larger for clams reared at 20?°C than those reared at 24?°C. These findings suggest that larval duration and growth, as well as settlement size, may vary markedly depending on temperature (and probably on season). The larval shell morphology of Manila clam can provide essential information about larval recruitment processes.     

文蛤动态能量收支模型构建、验证与应用

为评估文蛤生态容量,实验根据动态能量收支理论,基于R语言构建了文蛤动态能量收支模型,采用线性与非线性回归法估算模型参数,通过对比围塘环境下文蛤壳长、湿重、软体部湿重的实测值与模拟值验证模型,并应用于模拟黄海海域滩涂区文蛤的生长过程。结果显示,文蛤模型主要参数形状系数、阿伦纽斯温度系数和单位体积结构物质所需能量分别为0.57、9 278 K和2 056 J/cm³;实测与模拟的文蛤壳长、湿重和软体部湿重相关系数R²平均为0.996,模拟值与实测值的平均误差为3.58%;如东沿海区域6月实测文蛤软体部干重为0.48 g,壳长3.12 cm,模型模拟的软体部干重、湿重和壳长分别为0.476 g,6.6 g和3.2 cm。研究表明,实验构建的文蛤动态能量收支模型的准确度较高,可真实地反映出文蛤在自然水域中的生长过程,为评估文蛤生态容纳量及构建文蛤相关的生态系统模型提供科学参考。