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《水产科学》2015,(7)
在2.5m×4.0m×2.0m的水泥池中,按3.0×106尾/hm2的密度放养体长2~3cm、4~5cm和8~9cm的凡纳滨对虾。每种规格的对虾3口池塘,其中两口池塘在对虾养殖10d后,分别放入5尾体长为12.3~13.6cm和17.6~18.8cm的点带石斑鱼,另一池单独饲养凡纳滨对虾作为对照组。60d的养殖结果显示,单养池中2~3cm、4~5cm的凡纳滨对虾的质量增加显著低于混养(P0.05),但存活率显著高于混养(P0.05);混养时对虾规格越大增长越快,存活率越低,其中凡纳滨对虾2~3cm,点带石斑鱼17.6~18.8cm及凡纳滨对虾4~5cm,点带石班鱼17.6~18.8cm混养组合的质量增加最大(分别为7.88g与7.67g)。单养和混养时,8~9cm的凡纳滨对虾存活率差异不显著(P0.05)。方差分析显示,对虾规格与养殖模式间的交互作用对对虾质量增加和存活率影响极显著(P0.01);混养时对虾规格对鱼的质量增加影响不显著(P0.05),17.6~18.8cm的点带石斑鱼平均质量增加显著大于12.3~13.6cm(P0.05),对虾规格越大,混养鱼的捕食量越小,凡纳滨对虾8~9cm,点带石班鱼17.6~18.8cm的混养组合对虾存活率高,鱼虾的交互作用对鱼的质量增加和捕食量均有极显著影响(P0.01)。凡纳滨对虾混养的利润显著大于单养(P0.05),其中凡纳滨对虾4~5cm、点带石斑鱼17.6~18.8cm,凡纳滨对虾4~5cm、点带石斑鱼12.3~13.6cm,凡纳滨对虾2~3cm、点带石斑鱼17.6~18.8cm混养组合的利润显著高于其他混养组合(P0.05),凡纳滨对虾8~9cm的养殖利益显著低于其他规格对虾。建议凡纳滨对虾体长达到4~5cm开始混养点带石斑鱼。 相似文献
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饵料和养殖密度对中国对虾幼虾生长及存活率的影响 总被引：6，自引：0，他引：6
在实验用虾遗传背景一致的情况下,分析了3种饵料(配合饲料、冰冻鲜鱼肉和活卤虫)和4个不同的养殖密度对小水体中国对虾幼虾生长和存活率的影响。结果表明,饵料和饲养密度对中国对虾幼虾生长及存活率有显著影响。在饵料、养殖密度单因子实验及饵料和养殖密度相结合的双因子实验中,幼虾的生长均表现出极其显著的差异(P<0.01),活卤虫对幼虾生长的效应尤为突出。而养殖密度对中国对虾的行为生物学、个体间体重增量均有影响。随着养殖密度的提高,中国对虾增重变慢;同时,个体间体重增量差异变大。随着养殖密度的增加,中国对虾幼虾的存活率呈下降趋势,但不同饵料对存活率影响变化幅度较大,波动在58.1%～85.2%之间,其中投喂活卤虫养殖密度为50尾/桶的存活率最高(85.2%);投喂配合饵料4个养殖密度梯度的存活率变化不明显;而投喂冰冻鱼肉4个养殖密度梯度的存活率变化较大。因此,采用合适的饵料和养殖密度,能够提高中国对虾的生长速度,提高对虾养成存活率,改善生长过程中对虾群体体长、体重的整齐度。 相似文献
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南美蓝对虾(P.stylirostris)与南美白对虾形态相似、生活习性相近,比南美白对虾的成熟体形更大,生长速度更快,我国现有的养殖中国对虾和日本对虾的虾池都适合养殖它,尤其适合于北方沿海地区进行精养、半精养方式的养殖.笔者在南美蓝对虾养殖过程中,发现该品种具有6个明显优点:①抗病能力强,对病毒不甚敏感,因而养殖成活率高;②生长快,规格均匀,正常条件下,养殖80天～110天可生长到体长12cm～14cm,平均每10天体长增长1.2cm,如果比中国对虾晚放苗15天,而收获却可以提前15天左右,且增长率比中国对虾提高20%～30%;③对环境变化的适应能力强,换水量较小,为中国对虾的2/3,水环境稳定;④可以摄食普通饲料,蛋白质含量与中国对虾基本相同;⑤加工出肉率65%～68%,比中国对虾高出4%～5%,且肉质细嫩;⑥适宜于高密度养殖,放苗密度低则5000尾/亩,高则可达15万尾/亩. 相似文献
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在模拟工厂化养殖环境下开展日本囊对虾不同密度的生长与存活试验,实验设置5个密度水平,50、100、150、200、250尾/m~2,每个试验组设2个重复。结果表明,不同密度条件下,日本囊对虾生长性状、存活率与饵料系数存在显著差异(P0.05)。20日龄,不同密度间的生长性状无统计学意义差异(P0.05);40日龄,密度组间的生长性状存在统计学意义差异(P0.05),密度50、100、150尾/m~2显著大于密度250尾/m~2(P0.05);60日龄时,密度100尾/m~2的平均体长、腹长与体质量分别为(7.28±0.74)cm,(4.72±0.43)cm,(3.59±0.98)g,显著大于密度150、200、250(P0.05),为生长最快的密度组。密度对存活率有极显著影响,存活率变化范围为(23.98%±2.25%)~(69.95%±2.38%),密度50和250存活率分别最高和最低,密度50、100的存活率极显著大于密度150、200、250尾/m~2(P0.01)。饵料系数的变化范围为(1.63±0.08)~(3.99±0.31),最低为密度50尾/m~2,饵料系数1.63±0.08。最高为密度250尾/m~2,饵料系数为3.99±0.31。当密度低于100尾/m~2时,日本对虾生长表现最好,该密度下对虾生长速率快、存活率高、饵料系数低。本研究为日本囊对虾的工厂化养殖生产提供理论参考。 相似文献
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南美蓝对虾(P.stylirostris)与南美白对虾形态相似、生活 习性相近,比南美白对虾的成熟体形更大,生长速度更快,我国现有 的养殖中国对虾和日本对虾的虾池都适合养殖它,尤其适合于北方沿 海地区进行精养、半精养方式的养殖。笔者在南美蓝对虾养殖过程 中,发现该品种具有6个明显优点:①抗病能力强,对病毒不甚敏 感,因而养殖成活率高;②生长快,规格均匀,正常条件下,养殖 80天-110天可生长到体长12cm-14cm,平均每10天体长增长1. 2cm,如果比中国对虾晚放苗15天,而收获却可以提前15天左右, 且增长率比中国对虾提高20％-30％;③对环境变化的适应能力强, 换水量较小,为中国对虾的2／3,水环境稳定;④可以摄食普通 饲料,蛋白质含量与中国对虾基本相同;⑤加工出肉率65％-68％, 比中国对虾高出4％-5％,且肉质细嫩;⑥适宜于高密度养殖,放 苗密度低则5000尾／亩,高则可达15万尾／亩。 相似文献
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实验中国对虾 (FenneropenaeuschinensisOsbeck)的初始体重为 (0 .94 5± 0 .0 0 5 )g ( X±SE) ,投喂的饲料为人工配合饲料 ,实验的光照周期为 0L∶2 4D、2 4L∶0D、14D∶10L和 14L∶10D ,实验持续 35d。在 4种光照周期条件下 ,实验结果如下 :(1)中国对虾的特定生长率 (SGR)没有显著的差异 (P >0 .0 5 ) ;(2 )中国对虾的摄食量 (FI)没有显著的差异 (P >0 .0 5 ) ;(3)中国对虾的食物转化率 (FCE)没有显著的差异 (P >0 .0 5 ) ;(4 )中国对虾的蜕皮频率 (MF)不同 ,其中 ,2 4L∶0D和 0L∶2 4D下较低 ,14L∶10D和 14D∶10L下较高 ,且差异达到显著水平 (P <0 .0 5 )。实验结果表明 :光照周期影响中国对虾用在蜕皮上的能量分配 ,中国对虾的蜕皮频率存在一定的差异 (P <0 .0 5 ) ,但由于对中国对虾的摄食量和食物转化率没有影响 ,中国对虾用在生长的能量比例相近 ,故对中国对虾的生长未产生显著的影响。与光照强度和光谱组成对中国对虾生长的影响的研究结果相比 ,在中国对虾的集约化养殖生产中 ,光照周期的选择是次要的 相似文献
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虾池养殖牙鲆的试验与探讨 总被引：1，自引：0，他引：1
牙鲆( Paralichthys olivaceus )是鲆鲽类中的大型种,经济价值高,活鱼价格100～180元/kg.近几年辽宁工厂化养殖牙鲆已经成功,并获得很好的经济效益,但是室外土池养殖尚未开展,2000年4～11月,我们和青堆子运成水产有限公司合作,进行了虾池养殖牙鲆试验.7月1日在6.7 hm2虾池中放养平均体长11.2(8.1～12.5)cm牙鲆幼鱼8 532尾,之前45d曾投放中国对虾仔虾100万尾.至10月27日出池,获牙鲆2 584尾,平均体长(23.5±2.7)cm,平均体重(161.4±56.7)g,成活率30.3%.同时获对虾1000kg,虎鱼1 750kg.对虾池养殖牙鲆的前景作了初步探讨. 相似文献
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为研究荧光标记对小规格中国对虾的生长、存活率的影响以及荧光染料的保持情况,探讨VIE标记1 cm中国对虾的可行性,采用红色荧光染料标记体长为(1.14±0.06) cm的中国对虾2 856尾,暂养1 d后,将其中的2 321尾标记虾与6万尾同批非标记中国对虾混养于同一池塘进行了养殖试验。经112 d的饲养,结果发现,VIE标记对虾与非标记对虾在生长发育方面没有显著差异,但存活率低2.7 %;VIE标记保持情况良好,虽然标记点不如制作时集中,且位置有所变化,但无论是肉眼直接观测还是用紫外光源观测都能清晰可见。通过斑尾复虾虎鱼对标记虾的捕食试验,发现标记虾不会因身体上的VIE标记而增加被斑尾复虾虎鱼捕食的机率。 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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