Allometric and ontogenetic patterns related to feeding of a neotropical fish, Satanoperca pappaterra (Perciformes, Cichlidae)

Abstract –  This study aims to analyse whether Satanoperca pappaterra changes its feeding habit throughout ontogenetic development, and whether morphological ontogenetic patterns are related to its feeding habit and food capture. We collected 258 individuals in the Cuiabá river basin (Brazil) for analyses. There was a weak relationship between diet and body size, as evidenced by size class and multivariate analyses, and niche breadth did not vary strongly during ontogenetic development. Eight morphometric variables were measured in each individual. We found an isometric relationship for mouth height and width, and for head length. We found positive allometry for snout length and body height in relation to body length, whereas this relationship for intestine length and eye diameter showed negative allometry. These results suggest that morphology and consequently diet vary weakly during ontogenetic development of S. pappaterra .     

原油和燃油对南海重要海水增养殖生物的急性毒性试验

测定了南海原油、０号柴油和２０号柴油对３种仔虾、种仔鱼和４种贝类的急性毒性。油类对仔鱼和仔虾的毒性大小顺序为：０号柴油〉２０号柴油〉南海原油；对３种贝类（文蛤除外）的毒性大小顺序为０号柴油〉南海原油。油类分散液的毒性大于其水溶性组分。在曝油的３种仔虾中，刀额新对虾对０号柴油和２０号柴油的耐受力最弱，而日本对虾对南海原油最为敏感。曝油仔鱼对３种湍类的耐受力顺序为：黄鳍鲷〉前鳞鲻〉黑鲷，而七星鲈对０号     

淡水养殖鱼类主要细菌性传染病快速诊断的研究——鱼病诊断箱的应用试验

应用以葡萄球菌Ａ蛋白协同凝集试验（ＳＰＡ－ＣＯＡ）为主要检测手段的鱼病诊断箱，于１９９５￣１９９７年在吉林，辽宁等７省进行现场检测试验。结果，６１个渔场１１个品种的５１６尾病鱼有菌生长的２８５尾，经ＳＰＡ－ＣＯＡ鉴定阳性数为２３９尾，占有菌生长的８３．８６％，１２个渔场５个品种１２１６尾假定健康鱼有菌生长的为２８尾，经ＳＰＡ－ＣＯＡ鉴定阳性数为２２尾，占有菌生长的７８．５７％，认为本诊断箱适用于基     

Trophic structure of fish assemblages from Mamoré River floodplain lakes (Bolivia)

Abstract –  The fish assemblage of the floodplain of the Mamoré River (Bolivia) was estimated in eight lakes, corresponding to four habitat types, situated on an environmental gradient related to the river distance: lakes situated near the river, in the forested floodplain, at the floodplain edge and lakes isolated in the savanna. This paper documents the diet of 71 fish species (among the 140 recorded) and compares the taxonomic and trophic structure of fish assemblages between four lake types. The diet analysis was conducted to determine five trophic guilds: algivores/iliophages, herbivores, zooplanktivores, invertivores and piscivores. The taxonomic and trophic structures of the fish assemblages were not similar in the different lake types of the Mamoré River. The trophic structure of assemblages showed a coarse pattern of dominance of algivores/iliophages and invertivores, but different situations were observed in relative abundance of the trophic groups in relation to the spatial position of the lakes (except for piscivores). Lakes close to the river appeared more favourable to the microphages (algivores/iliophages, zooplanktivores) although remote lakes appeared more favourable to the macrophages (invertivores, herbivores). These results support the general idea that fish distribution follows a pattern linked to the ecology of the species, and related to environmental characteristics of the lakes.     

Cage culture of the Pacific white shrimp Litopenaeus vannamei (Boone, 1931) at different stocking densities in a shallow eutrophic lake

Postlarvae of Litopenaeus vannamei were acclimated and stocked in lake-based cages at the following stocking densities: 10, 20, 30 and 40 shrimp m⁻². Another set of shrimp was stocked in concrete tanks as reference samples at 30 shrimp m⁻². Significant differences were observed among stocking densities throughout the 95-day culture. The final weight at harvest decreased with increasing stocking density: mean weights of 23.3, 15.8, 13.0, 10.9 and 14.6 g for the 10, 20, 30, 40 shrimp m⁻² and reference tanks were observed respectively. There were no significant differences in survival throughout the culture period, ranging between 69% and 77%. Daily growth rates (range: 0.11–0.24 g day⁻¹) and specific growth rates (range: 3.54–4.34%) also differed significantly among stocking densities, both increasing with decreasing stocking density. The feed conversion ratio in the cages did not differ among the stocking densities, ranging from 1.53 to 1.65. The relationship between stocking density and mean individual weight at harvest followed the equation y =81.06 x ^−0.54 ( R ²=0.938) and that of stocking density and production (in g m⁻²) is y =58.01 x ^−0.46 ( R ²=0.834).     

微卫星标记在海洋经济贝类中的应用

微卫星标记是一种DNA分析手段,是种群遗传学研究中广泛应用的分子遗传标记。本文探讨了海洋贝类微卫星DNA的开发现状,介绍了微卫星的特点。阐述了微卫星标记技术应用于海洋贝类遗传多样性研究、遗传连锁图谱的构建、杂交子代的鉴定及杂种优势和繁殖成功率分析以及物种鉴定等方面的情况,并说明了微卫星标记技术存在的问题和发展趋势。     

A review of cyanobacterial odorous and bioactive metabolites: Impacts and management alternatives in aquaculture

Increased demand has pushed extensive aquaculture towards intensively operated production systems, commonly resulting in eutrophic conditions and cyanobacterial blooms. This review summarizes those cyanobacterial secondary metabolites that can cause undesirable tastes and odors (odorous metabolites) or are biochemically active (bioactive metabolites) in marine and freshwater, extensive and intensive aquaculture systems. For the scope of this paper, biochemically active metabolites include (1) toxins that can cause mortality in aquaculture organisms or have the potential to harm consumers via accumulation in the product (hepatotoxins, cytotoxins, neurotoxins, dermatoxins, and brine shrimp/molluskal toxins), (2) metabolites that may degrade the nutritional status of aquaculture species (inhibitors of proteases and grazer deterrents) or (3) metabolites that have the potential to negatively affect the general health of aquaculture species or aquaculture laborers (dermatoxins, irritant toxins, hepatotoxins, cytotoxins). Suggestions are made as to future management practices in intensive and extensive aquaculture and the potential exposure pathways to aquaculture species and human consumers are identified.     

淡水池塘主养鲈试验

报道了首次利用淡水鱼塘，主养鲈兼养鲢，鲤，草鱼等试验，每亩放苗５１５尾，鲈占放养总重的７１．７％；主喂冷冻青鳞鱼，约占７７．７％，辅喂人工配饵；前期只充渗漏水，中后期透明度小于３０ｃｍ时，大量换水。结果：共产商品鱼８８０２ｋｇ，其中鲈３７４０ｋｇ，折合亩产１２４．７ｋｇ，成活率８９％。总产值１２８０４６．８地，纯利７６９６９．８地，平均亩纯利２５６５元，投入产出比１：２．５。     

一种评价污染物对贝类生长影响的快速测定方法

简要介绍了新研制的贝类壳长电视测量仪的工作原理，及利用这一新的测试手段，根据不同实验条件比较实验的结果所建立的一套用来评价有毒物质对贻贝生长影响的测定方法。该方法快速灵敏、简便可行，在今后的生物测试和生物监测中具有广泛的应用价值。     

Feeding patterns in five predatory fishes of the high Paranà River floodplain (PR, Brazil)

Abstract— Between March 1992 and February 1993 five piscivorous fish species, Acestrorhynchus lacustris (Reinhardt, 1874), Hoplias malabaricus (Bloch, 1794), Rhaphiodon vulpinus Agassiz, 1829, Salminus maxillosus , Valenciennes, 1840 and Plagioscion squamosissimus (Heckel, 1840), of the high Paranà River floodplain showed a wide total prey spectrum though only three to four taxa were dominant in their diet. Shrimp, Macrobrachium amazonicum , were also common to the majority of species. Seasonal and spatial variations occurred throughout the study period probably due the availability of prey species. The main resources shared by the predators were also the most abundant in the area, with consumption markedly focused on prey about 5.0 cm long. Detrended correspondence analysis was effective in discriminating two groups of predators species that exploited distinct microhabitats. The predators with the least scores consumed small characids that inhabit mid-water or the littoral region, whereas those with the largest scores consumed prey associated to the bottom.