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为了探索斑点叉尾鱼回无公害健康养殖模式,提高鱼回鱼养殖技术,促进峡江县鱼回鱼产业化发展,我们于2 0 0 4年在江西省峡江县鱼种场利用美国大豆协会80 :2 0池塘养殖模式和全植物性蛋白豆粕型膨化浮性饲料进行了斑点叉尾鱼回夏花养至鱼种的示范试验,取得了良好的试验效果。三口试验池塘中斑点叉尾鱼回经过10 9d饲养后平均体重从1.0 7g长到38.81g。鱼的总产量为16 15 .4kg ,平均成活率为86 .8%。三口池塘饲料的平均系数为0 .96 ,净收入为16 46 .0 5元/亩,投资回报率平均为6 2 .3%。试验结果表明,设计合理的养殖模式,采用优质饲料,是实现健康养殖,获得良好经济效益的关键。 相似文献
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目前我国斑点叉尾鮰人工繁殖生产整体水平不高,苗种生产量一直上不去,据不完全统计,近几年全国斑点叉尾鮰苗种年生产量约在1000～2000万尾左右,造成苗种供求矛盾突出,影响了该鱼的推广养殖。笔者几年来通过对斑点叉尾鮰繁殖技术研究和生产实践,积累了一些技术经验,并每年生产近100万尾苗种供应各地养殖,出苗率由1990年25％提高到1993年的91％。现将斑点叉尾鮰人工繁殖的几个关键技术问题归纳一下,以供参考。 一、亲鱼培育 斑点叉尾鮰人工繁殖,生产上主要采用在原塘或产卵池放置产卵巢自然受精后收集卵块在孵化器进行人工孵化的方法。亲鱼培育是斑点叉尾鮰人工繁殖的 相似文献
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斑点叉尾鱼回原产于美国，是美国及非洲、欧洲等国家和地区的主要淡水养殖品种和食用经济鱼类。具有适温广、易饲养、食性杂、生长快、易捕捞等特点。受到广大养殖户普遍欢迎。我们合肥市水产技术推广中心站自１９９７年引进该鱼以来，经过几年人工繁殖试验，喜获成功，现将亲鱼培育时应注意几个问题小结如下。１亲鱼选择斑点叉尾鱼回亲鱼要求个体大、体型好、无伤无病，基因来源要求较好，这样亲鱼易驯化，也易养殖和培育。体重以１．５～５千克为好，年龄要求在３冬龄以上。２亲鱼池准备选择无渗漏、底泥浅、面积０．３３～０．６７公顷，… 相似文献
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密西西比大学水产养殖中心的科研人员将筛选出来的斑点叉尾鱼回ＵＳＤＡ 10 3品系与当地品系的斑点叉尾鱼回进行了生长、饲料效率、鱼片产量以及肉质比较。所用饲料的蛋白质含量分别为 2 6%、2 8%和 3 2 %。试验鱼规格为 3 2 .5ｇ/尾和 47.3 ｇ/尾 ,分别放养到 2 4个 0 .0 4ｈｍ2 的土池中 ,密度 185 3 0尾 /ｈｍ2 。每天进行饱食投喂 1次 ,养殖 5～ 10个月。测定结果摄食这 3种饲料的ＵＳＤＡ10 3品系的斑点叉尾鱼回 ,其增重率和饲料利用率均高于密西西比品系的斑点叉尾鱼回。组织分析测出 ,ＵＳＤＡ10 3斑点叉尾鱼回内脏的脂肪含量低、鱼… 相似文献
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斑点叉尾鱼回(Ictalurus punctatus)又称沟鲶,原产于美国密西西比河,是目前美国饲养规模最大的淡水鱼类,也是当前我国水产养殖中的一个优良新品种。河南省商丘鱼类良种场在虞城县北部的沿黄低洼盐碱地池塘中进行了斑点叉尾鱼回养殖试验,并获得成功,为沿黄低洼盐碱地池塘推广养殖斑点叉尾鱼回起到了示范作用。一、池塘条件用于养殖斑点叉尾鱼回的池塘位于黄河故堤南侧的低洼盐碱地上,为1998年开挖的土池,每个池塘面积约为6亩,东西走向,深2.5m,池底平坦、无淤泥,池塘保水、保肥性能好,进排水方便,且每个池塘配备有增氧机1台。养殖水源为农业… 相似文献
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斑点叉尾 鱼回 亦称沟鲶 ,属鲶形目 鱼回 科鱼类 ,是美国主要淡水养殖鱼类 ;该鱼具有适应范围广、食性杂、个体大、生长快 ,抗病能力强 ,肉质细嫩鲜美等优点。为了提高该鱼在北方池塘养殖产量 ,我们 1998年做了斑点叉尾鱼回 池塘苗种培育试验。1 材料与方法1 1 池塘条件本实验选在吉林农大水库渔场池塘 ;池塘面积 2 0亩 (斑点叉尾 鱼回 苗种培育池面积过大 ,不利于驯化饲养 ) ,养殖期间平均水深 1 5ｍ左右 ,池塘底泥在 2 0～ 30ｃｍ之间 ,注排水方便 ,水量充足 ,水质良好。 6月 18日全池用生石灰 2 6 0ｋｇ遍洒 ,6月 2 0日用网拉池底 … 相似文献
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斑点叉尾鱼回“传染性套肠症”是近年来在我国发生的一种斑点叉尾鱼回的新型细菌性传染病,危害很大,已经连续几年造成了大批的斑点叉尾鱼回发病死亡,严重地威胁着斑点叉尾鱼回养殖业的健康发展。目前初步认为该病是由嗜麦芽寡养单胞菌(Stenotrophomonasmaltophilia)引起的斑点叉尾鱼回的急性致死性传染病,以发生严重的肠炎、肠套叠和脱肛为特征,在短时间内即可引起大批的斑点叉尾死亡,我们称此病为“斑点鱼回叉尾鱼回传染性套肠症(InfectiousintussusceptionofchannelcatfishIICC)”。由于该病具发病突然,来势凶猛,传染快,呈流行性,死亡… 相似文献
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Association between the interannual variation in the oceanic environment and catch rates of bigeye tuna (Thunnus obesus) in the Atlantic Ocean 
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下载免费PDF全文 The environmental processes associated with variability in the catch rates of bigeye tuna in the Atlantic Ocean are largely unexplored. This study used generalized additive models (GAMs) fitted to Taiwanese longline fishery data from 1990 to 2009 and investigated the association between environmental variables and catch rates to identify the processes influencing bigeye tuna distribution in the Atlantic Ocean. The present findings reveal that the year (temporal factor), latitude and longitude (spatial factors), and major regular longline target species of albacore catches are significant for the standardization of bigeye tuna catch rates in the Atlantic Ocean. The standardized catch rates and distribution of bigeye tuna were found to be related to environmental and climatic variation. The model selection processes showed that the selected GAMs explained 70% of the cumulative deviance in the entire Atlantic Ocean. Regarding environmental factors, the depth of the 20 degree isotherm (D20) substantially contributed to the explained deviance; other important factors were sea surface temperature (SST) and sea surface height deviation (SSHD). The potential fishing grounds were observed with SSTs of 22–28°C, a D20 shallower than 150 m and negative SSHDs in the Atlantic Ocean. The higher predicted catch rates were increased in the positive northern tropical Atlantic and negative North Atlantic Oscillation events with a higher SST and shallow D20, suggesting that climatic oscillations affect the population abundance and distribution of bigeye tuna. 相似文献
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In this experiment, a feeding trial was performed to determine the effects of fructooligosaccharide (FOS) on growth performance, digestive enzyme activity and immune response of Japanese sea bass, Lateolabrax japonicus juveniles (initial weight 38.3 ± 0.5 g), and the fish were examined following feeding with six levels of FOS (0, 0.5, 1, 2, 4 and 6 g/kg) for 28 days. Significant enhancement of weight gain (WG) and specific growth rate (SGR) was found in fish fed 1 g/kg FOS incorporated diets (p < .05), while the feed conversion ratio (FCR) in the 1, 2 g/kg FOS groups reduced significantly compared with the control (p < .05). Besides, the crude lipid in the 4, 6 g/kg FOS groups increased significantly compared with the control (p < .05). On the other hand, the erepsin and lipase activities significantly elevated in intestine of fish fed 2 g/kg FOS (p < .05) and the lysozyme activity in serum of fish fed 2 g/kg FOS were significantly higher than that in the control (p < .05). Moreover, the alkaline phosphatase activities in serum of fish fed 0.5, 1, 2 g/kg FOS were significantly higher than in control (p < .05). Regression analysis showed that the relationships between dietary FOS levels and either SGR, FCR, erepsin or lysozyme activities were best expressed by regression equations, and the optimal inclusion levels are 1.37, 1.80, 3.06, 3.11, 1.93 and 1.80 g/kg for SGR, FCR, erepsin, lipase, lysozyme and total superoxide dismutase activities, respectively. Overall, this study revealed that FOS incorporated diets could beneficial for L. japonicus culture in terms of increasing the growth, digestion and immune activities. Under the present experimental condition, the optimal supplementary level of FOS in the diet of L. japonicus is 1–3 g/kg. 相似文献
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Liping Li Rui Wang Wanwen Liang Xi Gan Ting Huang Yan Huang Jian Li Yunliang Shi Honglin Luo Ming Chen 《广西水产科技》2014,(1)
Previously, we reported 10 PEGE types of 85 tilapia Streptococcus agalactiae(GBS), which shifted from Streptococcus iniae in China, by using PEGE method. Presently, larger and more representative tilapia GBS were isolated, for the ?rst time in China, to characterize their serotypes and genetic diversities more precisely than had done before. 168 GBS strains were distributed in ?ve provinces of China, in which Guangdong, Guangxi and Hainan were the major ones, holding36.9%(62/168), 37.5%(63/168) and 19.6%(33/168), respectively. Serotypes, Ia, Ib and III, were observed in these strains and the most predominant one was Ia(95.2%), which mainly distributed in Guangdong, Guangxi and Hainan. Ia initially occurred in 2009, it shoot up to 32.1% in 2010,but decreased to 16.1% in 2011 before went up to 45.2% in 2012. Ib sporadically occurred during2007–2011, III onlyoccurred in 2012. 14 different PFGE types, including 4 new types(N, O,P and Q), were observed, in which B, D, F and G were the predominant types, holding 83.9%(141/168) of the total GBS strains. Ia corresponded to 11 PFGE types(A–H, N–P), in which type D predominated(51%). Ib represented 3 genotypes(I, J and Q) and III harbored only 2genotypes(N and F). Type N and Fsynchronously presented in Ia and III. In summary, the genetic diversity of tilapia GBS varied by serotypes and changed with geographical locations and years.Although Iastillpredominated, new rareserotypeIII alreadyoccurred in China. 相似文献
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Iciar Martinez Amaya Velasco Ricardo Pérez-Martín Eskil Forås Michiaki Yamashita Carmen G. Sotelo 《Journal Of Aquatic Food Product Technology》2013,22(4):289-297
The purpose of this work was to evaluate the suitability of a method based on the presence of two restriction sites (for Hae III and Hindf I) in the mitochondrial NADH dehydrogenase subunit 5 (mt ND5) gene to identify Scomber species. The evaluation was performed on 144 reference and market samples by sequencing of the entire 505-bp fragment of the mt ND5 gene and of a 464-bp fragment of the Kocher fragment of the cytochrome b gene (mt Cytb). Sequence analysis of any of the two fragments allows the identification of each of the four Scomber species, but S. japonicus and S. colias had the same restriction sites at the ND5 amplicon and would not have been differentiated by this analysis. Similarly, loss of the Hae III site in some S. scombrus individuals would have misidentified them as not being Scomber. All the market products were correctly labeled except one acquired in Spain labeled as originating in the Atlantic and containing S. japonicus. 相似文献
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Growth hormone (GH) and reproduction: a review 总被引：5，自引：0，他引：5
Florence Le Gac Odile Blaise Alex Fostier Pierre-Yves Le Bail Maurice Loir Brigitte Mourot Claudine Weil 《Fish physiology and biochemistry》1993,11(1-6):219-232
Interaction between growth and reproduction occurs in many vertebrates and is particularly obvious at certain stages of the life cycle in fish. Endocrine interactions between the gonadotropic axis and the somatotropic axis are described, the potential role of GH being emphasised. A comparative analysis of these phenomena in mammals, amphibians and fish, suggests a specific role of GH in the physiology of puberty, gametogenesis and fertility. It also shows the original contribution made by studies on the fish model in this field of investigations. 相似文献
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Two gonadotropins (GtH; Qa and Qb) were purified by gel filtration and ion exchange chromatography from the pituitaries of Indian walking catfish (Clarias batrachus). The presence of GtH during purification was assessed by in vitro oocyte maturation and in vivo steroidogenic activity, and their identities were determined by elution profiles, molecular weight, biological activities and yield. The molecular weights of Qa and Qb were 37 and 42 kDa, respectively, and composed of distinct subunits (Qa: 20 and 14 kDa and Qb: 26 and 18 kDa). Polyclonal antibodies raised against Qa immunostained Qa, Qb and pituitary GtH cells. A competitive Qa‐ELISA was developed whose sensitivity was 6.25 ng mL?1 (1.25 ng well?1) with intra‐ (3.5%) and inter‐ (12.4%) assay coefficients of variation. Displacement curves parallel to the standard were obtained with plasma and pituitary extracts of catfish, Qb and carp GtHII. The assay was validated by measuring the plasma Qa levels after LHRH treatment and in relation to ovarian growth in the female catfish during different reproductive phases. Based on the results, Qa and Qb corresponded to fish LH and FSH respectively. The findings will increase the knowledge of the mechanisms controlling fish reproduction and identification of sensitive phases in fish in captivity for hormonal manipulation. 相似文献
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Controlled infection of Poecilia reticulata Peters (guppy) with Tetrahymena by immersion and intraperitoneal injection 下载免费PDF全文
下载免费PDF全文 G Sharon M Pimenta‐Leibowitz M C L Vilchis N Isakov D Zilberg 《Journal of fish diseases》2015,38(1):67-74
Tetrahymena is a protozoan parasite, which infects guppy, Poecilia reticulata Peters, and causes substantial economical losses in commercial farms worldwide. Studies of guppy infected by Tetrahymena require standardized infection protocols. The LD50 for Tetrahymena infection of guppies by intraperitoneal (IP) injection was calibrated, and the level obtained was 946 parasites per fish. Guppy infection with Tetrahymena by immersion, imitating the natural route of infection via the integument, was studied under normal or stress conditions. Exposure to cold and netting (CNI) and to cold only (CI) followed by immersion exposure to 10 000 Tetrahymena per mL resulted in 22.5% and 19.2% mortality, respectively, as compared to 14.2% and 10% in groups that were netted only (NI) or non‐stressed (I). Histopathology revealed that immersion infection resulted in a systemic infection. Lysozyme levels, measured 3 weeks after infection, were significantly higher in the CNI group (288 μg per mg protein) compared with CI‐, NI‐ and I‐treated groups (94.5, 64 and 62.3 μg mg?1, respectively). There was no evident parasite immobilization activity in body homogenates, suggesting no development of acquired immunity. Re‐infection by IP injection revealed no increase in protection in any of the treatment groups, mortality range of 56.3–75%, higher than in the non‐exposed control (40.6% mortality). 相似文献
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