Aphanomycosis of crayfish: crayfish plague

This is the Aphanomycosis of crayfish: crayfish plague report produced by the Environment Agency in 2000. Crayfish plague is an extremely virulent fungal disease of European crayfish species, the white clawed or stone crayfish of Western Europe Austropotamobius pallipes, the Noble crayfish of northern Europe Astacus astacus and the narrow clawed crayfish of Eastern Europe, Astacus leptodactylus. The white claw crayfish A. pallipes is the indigenous native crayfish of the British Isles. Until the early 1980s there were extensive healthy populations of this crayfish in almost all suitable alkaline river and lake environments in England and Wales as far north as Northumberland. The conservation importance of this native crayfish is widely recognised. This report provides a general review of the literature of crayfish plague, including an overview of its spread through the British Isles from CEFAS records. Information on current diagnostic methods from the Office International des Epizooties (OIE) Aquatic Disease Manual is provided. Information on the taxonomy, morphology and physiology of the pathogen is reviewed, together with the pathogenicity and pathology of the disease and current means of prevention and control.

Geocronologia (40Ar/39Ar e U-Pb), petrografia e litogeoquímica da intrusão alcalina do Marapicu RJ

A intrusão alcalina do Marapicu é uma intrusão localizada no maciço Marapicu-Gericinó-Mendanha situado na região metropolitana do Rio de Janeiro. Este maciço é formado por dois corpos alcalinos: Marapicu e Mendanha que fazem parte do lineamento magmático Poços de Caldas-Cabo Frio. Este lineamento inclui dezenas de corpos ígneos alcalinos de idade Cretácea com uma direção preferencial WNW-ESE. Os litotipos mais abundantes do Maciço Marapicu são representados por nefelina sienitos e sienitos de caráter plutônico, além de, fonolitos caracterizados por intrusões rasas geralmente em forma de diques. Além desses litotipos foram amostradas duas rochas com características químicas de magma parental (lamprófiro e fonolito tefrítico), porém, essas duas amostras não apresentam relação genética com as demais. Também foi amostrado um nefelina sienito que possui sodalita azul como feldspatóide, sendo assim, chamado de nefelina sodalita sienito. Entre os fonolitos coletados para esse trabalho, uma amostra apresenta granada melanita em sua assembleia mineralógica, e esta foi então denominada melanita fonolito. Quimicamente as rochas do Marapicu formam uma série alcalina predominantemente insaturada em sílica, miaskítica e metaluminosa. Dentro desta série se observam duas suítes sendo uma potássica (predominante) e outra sódica. A evolução química do corpo se deu por processo de cristalização fracionada com ou sem assimilação de crosta continental provavelmente dentro de uma fonte mantélica enriquecida. Duas idades de cristalização foram obtidas para o Maciço do Marapicu sendo uma idade 40Ar/39Ar de 80,46 0,58 Ma em hornblenda, e uma idade U-Pb em zircão bastante concordante de 78,0 2,1 Ma. Os dados apresentados aqui em conjunto com dados da literatura apontam para dois modelos geodinâmicos de geração dos corpos alcalinos do sudeste brasileiro, um considera a existência de uma pluma mantélica gerada na astenosfera, o outro tem por base a hipótese de flexura crustal e considera que a carga de sedimentos depositados na plataforma continental exerceria esforços que provocariam fraturas profundas permitindo a ascenção desses magmas. O presente trabalho vem para contribuir no entendimento do alojamento dos corpos alcalinos do sudeste brasileiro através do estudo especifico do Maciço Marapicu em conjunto com dados da literatura

Reserved parking : marine reserves and small-scale fishing communities: a collection of articles from SAMUDRA report

As the earth’s resources continue to face increasing pressure from a variety of human and natural causes, protection of the environment and biodiversity is a matter of contemporary concern, The conservation of coastal and marine resources, in particular, has become a priority for countries around the world. In this context, marine protected areas (MPAs) are being widely promoted as one of the most effective tools for the conservation of coastal and marine resources. Most MPAs are located in coastal areas of great biodiversity, and hence their development has direct impacts on the lives and livelihoods of coastal communities, especially small-scale and traditional fishing communities. Typically, they are the ones who have to bear the costs of conservation practices–lost livelihood options, expulsion from traditional fishing grounds and living spaces, and violation of human/community rights, to name a few. The articles in this dossier, drawn chronologically from the pages of Samudra Report, the triannual publication of ICSF, draw attention to these issues. They show that conservation and livelihoods are closely intertwined, and that top-down, non-participatory models of conservation can be counter-productive. Despite being poor and powerless, fishing and coastal communities can be powerful allies in conservation efforts, given their longstanding dependence on natural resources and their traditional ecological knowledge systems. As the examples in this dossier reveal, it is possible for fishing communities to protect and conserve the environment, while continuing with sustainable fishing operations. Clearly, only an integrated approach to fisheries management and conservation will prove successful. This dossier will be useful for policymakers, social scientists, non-governmental organizations and others interested in fisheries, conservation, communities and livelihoods.

Global transcriptional responses of the toxic cyanobacterium, Microcystis aeruginosa, to nitrogen stress, phosphorus stress, and growth on organic matter

Whole transcriptome shotgun sequencing (RNA-seq) was used to assess the transcriptomic response of the toxic cyanobacterium Microcystis aeruginosa during growth with low levels of dissolved inorganic nitrogen (low N), low levels of dissolved inorganic phosphorus (low P), and in the presence of high levels of high molecular weight dissolved organic matter (HMWDOM). Under low N, one third of the genome was differentially expressed, with significant increases in transcripts observed among genes within the nir operon, urea transport genes (urtBCDE), and amino acid transporters while significant decreases in transcripts were observed in genes related to photosynthesis. There was also a significant decrease in the transcription of the microcystin synthetase gene set under low N and a significant decrease in microcystin content per Microcystis cell demonstrating that N supply influences cellular toxicity. Under low P, 27% of the genome was differentially expressed. The Pho regulon was induced leading to large increases in transcript levels of the alkaline phosphatase phoX, the Pst transport system (pstABC), and the sphX gene, and transcripts of multiple sulfate transporter were also significantly more abundant. While the transcriptional response to growth on HMWDOM was smaller (5–22% of genes differentially expressed), transcripts of multiple genes specifically associated with the transport and degradation of organic compounds were significantly more abundant within HMWDOM treatments and thus may be recruited by Microcystis to utilize these substrates. Collectively, these findings provide a comprehensive understanding of the nutritional physiology of this toxic, bloom-forming cyanobacterium and the role of N in controlling microcystin synthesis.

新疆紫草细胞悬浮培养生产紫草宁衍生物的动态测定机理化因子调控

本文在本实验室提供的新疆紫草愈伤组织高产系A1的基础上，采用二步培养法，进行摇瓶悬浮培养，分别在生长及生产培养基中测定了细胞生长，次生产物合成，培养基的C源（蔗糖）消耗，溶氧，电导率和pH值的动态变化曲线，确定了各动态曲线之间的关系，为进一步的放大培养提供了参考依据。同时，还测定了与细胞生长密切相关的过氧化物酶及与产物合成密切相关的苯丙氨酸解氨酶(PAL)的活性的动态变化曲线，进一步将宏观参数的动态变化与微观参数的动态变化联系起来。 本文还对不同理化因子对生产培养基中悬浮培养的细胞的生长及紫草宁衍生物合成的影响进行了研究。结果表明：过高或过低的供氧水平均不利于细胞的生长及产物的合成;C源及N源有较好的协同作用，适当地提高C源及N源的水平能明显提高紫草宁衍生物的产量：接种前往培养基里加入一定量的前体苯丙氨酸( Phe)，能明显提高紫草宁衍生物的产量，而在培养中期添加则有一定的负致应;一定量的拜土及琼脂(agar)的添加，对产物的合成均具有正效应，并且作用大小和细胞的生理状态有关。高密度培养的研究表明，在合适的接种量和培养基浓度下，适当提高溶氧，较大幅度地提高产量是有可能的，这还有待于进一步的研究验证。

稀土元素生物效应的蛋白质组学研究

蛋白质组学是研究细胞内全部蛋白的动态表达及其相互关系的新兴学科，是功能基因组学研究的重要组成部分和战略制高点，广泛应用于生命科学的各个领域，研究对象涵盖微生物、动物和植物等。 　　稀土元素（rare earth elements），亦称镧系元素（lanthanides），是性质相似的15种金属元素。随着稀土元素在工业、农牧业和医疗等领域的应用日益深入，它们对生物体的作用机制亟待研究。生物固氮作用为生命世界提供75%的绿色氮源，根瘤菌是重要的固氮微生物，具有基因组结构简单、培养周期短等特点。酿酒酵母是与人类关系最密切的一种酵母，不仅因为传统上其用于制作食品及酿酒，而且是现代分子生物学和细胞生物学中的真核模式生物。为了全面地了解稀土元素对细胞的作用，我们运用高分辨率的蛋白质双向电泳分离技术和高通量的蛋白质质谱分析手段以及生物信息学等方法，分析了稀土元素钆（Gadolinium，Gd）在原核生物费氏中华根瘤菌（Sinorhizobium fredii）USDA205和真核生物酿酒酵母（Saccharomyces cerevisiae）YM4271的生物效应。 　　结果表明，经1mM Gd(NO3)3处理12小时后，费氏中华根瘤菌USDA205中 22个蛋白质表达有差异。这些蛋白质可根据功能分为8类，包括转运蛋白、胁迫相关蛋白、代谢相关蛋白等。其中13个蛋白质表达量增加，9个蛋白质表达量下降。膜蛋白在差异蛋白中占有很大比重。另外，我们分析了不同浓度的钆处理后蛋白质表达的变化情况，发现蛋白质组的变化是与处理浓度密切相关的。研究中还发现同种浓度的钆与另一种稀土元素铒（Erbium，Er）相比，离子半径较小的铒离子对根瘤菌的抑制作用更加明显。 　　比较不同浓度的钆对酿酒酵母YM4271的影响，发现酵母对稀土元素的反应不及根瘤菌敏感，对数生长初期的酵母经钆处理12小时或24小时后均无显著变化。 　　本研究首次用蛋白质组学的方法研究稀土元素对微生物的作用，鉴定了一些有价值的蛋白质，并得到了它们的表达特点和相关数据，为更好地理解稀土元素的生物效应提供了有力的分子生物学证据。 　　

松嫩平原碱化草地景观空间格局及环境因子的综合分析

本文对松嫩平原羊草地的群落结构及空间格局进行了分析，主要内容包含以下三个方面： 1、本文第一部分是对碱化草地植物群落分布的空间、环境因子分离。决定碱化草地植物物种在空间分布的因素可以大致分解成4个部分：（1）通过物种的生态位起作用的环境因子;（2）决定物种、群落间竞争激烈程度的空间距离因子;（3）环境和空间因子的交叉或耦合作用;（4）其它未知因子（如生物和随机因子）。本研究在1996年野外实地采样的基础上，运用DCA消势对应分析（Detrended Correspondence Analysis）对群落主要变化趋势及其与土壤环境因子之间的关系进行了分析。运用DCCA消势典范对应分析（Detrended Canonical Correspondence Analysis）对影响松嫩平原碱化草地群落结构季节动态的空间和环境因素进行了定量的分解。结果表明： 在影响群落分布的各因子中，环境因子独立约占40％，而环境一空间耦合因子占35％，空间因子独立约占3％，其它因子约占20％。在诸多因子中，土壤的盐渍化程度在整个生长季起着决定性作用，但土壤水分和氮素的作用因季节而变化。在干旱季节，植物生长的主要制约因子表现为土壤碱化度和土壤水份，而土壤氮素的作用处于次要地位。但在降雨较多、土壤湿润度较大的季节，土壤氮素的影响明显增强，成为仅次于土经度的决定性因素。 2、第二部分对东北松嫩平原碱化草地植物群落空间格局的分形性质进行了分析，分别用边长－面积指数和Korcak指数估计了斑块边界复杂性和斑块面积分布的分形维数。结果表明： 随放牧强度增加，占优势的羊草斑块的相对斑块化加剧，而斑块的边界在中度放牧时最不规则： 在水淹地，占优势的羊草斑块和次优势的碱茅斑块、獐茅斑块的斑块边界复杂性和斑块化程度比未水淹地都低，说明水降低了群落复合体内的异质性： 水淹地优势植物斑块的边长－面积指数和Korcak指数均低于次优势种，但在重度放牧地结果好相反，说明两种样地处于不同的演替阶段; 斑块边界复杂性符合同一尺度规律，在现有的面积范围以内没有尺度转换，而斑块面积分布则存在尺度转换点。对重牧地和水淹地的尺度分析表明，较小尺度上， 群落空间格局的相对斑块化程度较低，说明较小尺度上的空间格局要相对稳定一些，而较大尺度上则相反。可能原因是放牧干扰对大尺度的斑块影响更大。 3、对1989年开始围栏封育的样地10年来的空间格局变化进行时间序列分析，研究恢复演替过程中各个主要斑块类型的分布特征及动态，以及整个样地总体格局在演替系列中的变化。得出如下结果： 羊草是该区植被的优势种，其格局动态为：1989－1993年，羊草斑块总面积增加，斑块数目减少，相对斑块化指数降低，1994年后羊草的空间格局基本稳定。 羊草的斑块面积分布曲线在20平方米左右发生转折，即空间格局在此尺度发生尺度转换。不同尺度上斑块的相对斑块化指数及其在恢复演替中的变化趋势不同：小斑块的相对斑块化指数低，在1989－1993年期间增加，而后降低;大斑块的情况正好相反。说明羊草空间格局的主要变化之一是中等大小斑块的合并和数目减少，羊草斑块生长对格局的影响比斑块合并的影响要小。 獐茅斑块的格局动态为：1989－1994，斑块总面积、斑块数目、最大斑块面积增大，1995年开始降低。相对斑块化程度则先降后增。碱蓬斑块在1989－1993年间的格局动态与羊草正好相反：总面积减少，斑块数目增加，斑块面积大小的变化范围变窄，说明1993年之前，控制碱蓬斑块的主要生态学过程是其他物种的侵入，隔离原来较大的斑块，同时占据某些小斑块。1994年之后，碱蓬斑块的变化比较随机，其格局变化受到其他物种如杂草对策种虎尾草等的影响很大。 样地总体格局的变化为：1991年前，斑块种类和总斑块数目增加，斑块化程度随着增大;1993年后，斑块种类基本稳定下来;1991－1995，斑块化指数降低。在此期间，斑块数目增加，所以斑块化程度降低意味着斑块大小频率分布趋于均匀，大斑块被分裂，小斑块在长大，群落总体空间格局逐渐稳定。总体格局在三个尺度上有不同的自相似规律，这三个尺度分别为：La(a)<=1; 15.5。小尺度上相对斑块化程度低，但年际间变化较中尺度剧烈;中尺度相对斑块化程度变化较为缓，大尺度上，斑块分布一直趋于减少最大的斑块数目。总的变化趋势为，随恢复演替的深入，最大和最小的斑块数目都减少，处于中间尺度的斑块最多。

Histochemical studies on the olfactory epithelium of some hillstream teleosts

Living specimens of Barilius bendelisis, Crossocheilus latius latius, Torputitora, Glyptothorax pectinopterus and Pseudecheneis sulcatus were collected from the streams and rivers of Garhwal Himalaya. Histochemical localization of carbohydrates (1:2 glycol groups, glycogen, B-metachromasia and acid mucopolysaccharides), proteins and protein bound NH sub(2) group, bound lipids and the enzymes (acid and alkaline phosphatases) in the olfactory epithelium were studied. The receptor, supporting basal and mucous cells show varying degrees of distinction and distribution of these substances. The enzymes are present on the surface of the epithelium, sensory hairs and the boundaries of mucous cells only.

Hydrological studies of Matatilla Reservoir, Uttar Pradesh

Matatilla Reservoir, located in semi arid region, (Lat. 25 degree 15'N and Long. 78 degree 23'E) has an area (at FRL) of 13,893 ha, volume and shore development 0.663 and 1.65, shoreline 73.6 km. Volume and shore development indicate that greater part of the reservoir is shallow, which is a favourable point for fish productivity. Temperature and dissolved oxygen gradually decreased with the increase in depth. Carbon dioxide was absent from the surface but invariably present in the bottom (3.6 ppm) pH remained alkaline (7.2-8.4 ppm) throughout the year. Alkalinity, chloride, calcium, magnesium, hardness and priductivity was maximum in pre-monsoon and minimum in monsoon except for calcium and manganesium in post-monsoon. Phosphate, nitrogen and ammonical nitrogen were found in traces. These variations may be due to influx and outflow of water and use of reservoir water for multipurpose activities.

Soil quality of Bhilwara District (Rajasthan) in relation to pisciculture

The present paper deals with the physico-chemical data of 13 rainfed and drainable dry bundhs of Bhilwara District (India). All the dry bundhs studied showed a slightly alkaline pH ranging from 7.5 to 8.5. Electrical conductivity ranged from 2 to 8 millimhos/cm. Organic carbon in sediment fluctuated from 0.30 to 0.75%. Nitrogen, phosphate and potassium levels were fairly good, at 30 to 50 and 24 to 36 mg/100 g of soil respectively. Based on these data it was inferred that these dry bundhs were highly productive and suitable for freshwater fish culture.

Studies on some physico-chemical factors of Kaptai lake

The present investigation dealt with the climatic and some physico-chemical conditions of the Kaptai lake with respect to their monthly variation. Air temperature was found always higher than water temperature. Vertical variation in temperature (0.8-4.7°C) was observed in all months. The water level fluctuates appreciably throughout the year. Wide seasonal fluctuations were also noted in water transparency. The lake was found to be slightly hard and alkaline pH. Dissolved oxygen (DO) (6.4-9.1 mg/l) and free carbondioxide (4.7- 6.0 mg/l) contents showed favourable condition for aquatic lives. DO at different depth has shown no wide variation (1.0-2.4 mg/1). Conductivity ranged between 91.9±7.1 and 106.4 ±5.2 mS/cm.

Phosphate treatment of frozen prawns. Pt 2. Frozen storage characteristics of prawn meat treated with polyphosphates

This communication reports the changes in physical, organoleptic and biochemical characteristics of prawn meat dip-treated with alkaline and neutral solutions of polyphosphates during frozen storage. Results are presented on changes in thawed and cooked yields, water extractable nitrogen, non-protein nitrogen, free amino-nitrogen, salt solubility, myosin and moisture in the muscle and loss of soluble nitrogenous constituents in thaw drip during frozen storage up to seven months. The salt solubility remained unchanged during storage in samples treated with neutral polyphosphate solutions and the organoleptic quality was superior to control sample. It is concluded that dip treatment with neutralized solutions of tripolyphosphate not only maintains correct drained weight and improves cooked yield during prolonged frozen storage but also protects the frozen product from denaturation as measured by the salt solubility of the proteins.

Changes of enzymatic activity during larval development of carp, Catla catla (Ham.)

Quantitative assays of trypsin, amylase and alkaline phosphatases were made in relation to age and food during the larval development of the Indian major carp Catla catla. The responses of all the test enzymes to age and food were identical. No enzymes were detected from the fertilized eggs. Detectable amount of enzymes were first observed in the first day old hatchlings. All the test enzymes in the group fed normal feed tended to rise gradually with advancement of age till day 22 after which an asymptotic level was attained. Absence of food throughout the rearing period caused the enzymatic activity of the larva to remain at the lowest level throughout. When starvation was followed by feeding, enzymatic activity in the former group was consistently higher than that of latter, suggesting that feeding activity was primarily responsible in maintaining the enzymatic activity of carp larva. The enzymatic activity of zooplankton was significantly higher than carp larva till day 6 to 12 after which the latter exceeded the former implying that carp larva during development utilizes the exogenous enzymes of zooplankton.

Effect of fertilizer carbamide on proteolytic enzymes of fish Labeo rohita

Specific activities of acid, alkaline and neutral proteases in liver, muscle, brain, and gill of fish exposed to 50 ppm ambient carbamide for 15, 30 and 60 days and in control were estimated. It was observed that carbamide even at low concentration of 50 ppm inhibited proteolysis and favoured protein synthesis.