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1.
2005-2006年度,两年共利用800 kg亲贝进行了4批育苗,获得受精卵2.33×1010粒,D形幼虫15 734×1010粒,平均孵化率68.8%。受精卵经22~25 d的培育,稚贝规格达210~296μm,2005、2006年度单位水体出苗量分别为1.315×106粒/m3、2.797×106粒/m3,出池稚贝的平均壳长分别为265μm、228μm。分别采用干露法和用常温阴干刺激加流水法进行催产,平均每千克亲贝所获得的受精卵、D形幼虫及孵化率前者分别是后者的33.5%、20.32%和60.6%。 相似文献
2.
本文对青蛤工厂化育苗,高产技术关键进行了阐述.结果表明;自然发育成熟的亲贝和促熟强化培养的亲贝,催产率可达100%;水温26～29℃时,受精率达88%～93%左右;受精卵密度30～35个/ml,孵化率达82%～90%,D形幼虫培养密度6～11个/ml,5～6d,附着变态.用250～300目筛绢过滤海泥,附着率达80%～82%.工厂化育苗.对亲贝选择,育苗密度,饵料供应,选优培养,"倒池"扩苗和附着基选用,作了重点说明.在150个育苗池内,每池规格45 m3水体(7.5m×4.0m×1.5m),平均池育苗量19.35 kg,共培育出80～200万粒/kg的稚贝2902.50 kg. 相似文献
3.
2005-2006年度,共利用800 kg亲贝进行了4批育苗,获得受精卵2.33×10^10粒,D形幼虫15734×10^10粒,平均孵化率68.8%。受精卵经22～25 d的培育,稚贝规格达210～296μm,2005、2006年度单位水体出苗量分别为1.315×10^6粒/m^3、2.797×10^6粒/m^3,出池稚贝的平均壳长分别为265μm、228μm。分别采用干露法和用常温阴干刺激加流水法进行催产,平均每千克亲贝所获得的受精卵、D形幼虫及孵化率前者分别是后者的33.5%、20.32%和60.6%。 相似文献
4.
剌参大水体育苗,采用降低初耳幼体放养密度,适当减少单胞藻投喂量、加大换水量、通气、增设机动进水系统等措施,培育出稚参1911.5万头,幼参258.36万头,单位水体平均出苗量稚参为3.823万头/m~3,幼参为5167头/m~3。以食用鲜酵母为饵的耳状幼体能正常发育变态,稚参出苗量平均达1.6万头/m~3。稚参的附着、成活,成长与附着基的规格有关。 相似文献
5.
菲律宾蛤仔人工育苗技术 总被引：2，自引：0，他引：2
2003年锦州市政府制定了天桥开发区浅海10万hm~2 (150万亩)贝类增养殖发展规划,以菲律宾蛤仔为主。为此我们进行了菲律宾蛤仔室内人工育苗,2004年5月共出稚贝4.3亿粒,单位面积出苗量391万粒/m~2,2004年7月 28日成功进行了浅海底播,目前长势良好,该项目获得锦州市科技攻关奖。现将育苗技术介绍如下： 1 材料与方法 1.1 试验材料海水育苗室1座,育苗池132m~3,池规格为14～25 m~3/池。单胞藻培养用5 L 三角烧瓶150个,体积为0.5 m~3/ 袋的塑料袋150个。种贝50 kg,体长3.28cm。镀塑铁笼100个,30目细沙3m~3。 1.2试验方法 1.2.1单胞藻培养2004年4月15日,开始培养单胞藻叉鞭金藻、小球藻各5 L,营养盐用康威液。到7月11日结束。 相似文献
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缢蛏工厂化育苗技术的研究 总被引：2，自引：0，他引：2
利用现有的对虾育苗设施,进行缢蛏人工催产,浮游幼虫和稚贝培育,提供缢蛏养殖户所需苗种,获得成功。1997年出池稚贝平均密度76.26×10~4颗/m~2(壳长501～920μm),最高密度111.15×10~4颗/m~2(壳长501～811μm) 相似文献
8.
随着魁蚶养殖生产规模的扩大,对苗种的需求量也逐年增多,1990—1991年两年中我厂共利用100m~3的培育水体进行了魁蚶的室内人工育苗试验,共培育出400微米的稚贝1亿粒,海上中间育成,共分出0.5cm 以上的幼苗800万粒,单位水体出苗量达到8万粒。现总结如下经验:一、亲贝的暂养魁蚶亲贝的暂养主要有三种方式,即池底暂养、扇贝养成笼暂养和单层浮动网箱暂养。一般以单层浮动网箱暂养为好,网箱的规格应视培育池的大小而 相似文献
9.
锯缘青蟹工厂化规模育苗技术的研究 总被引：2，自引：0，他引：2
1998年投入育苗用抱卵蟹44只,孵化蚤状幼体(Z_1)6250万只,育成大眼幼体409.76万只,平均成活率达到6.56％,平均单位水体出苗量达到6180只。稚蟹培育,投入大眼幼体409.76万只,培育出稚蟹(C_2～C_6)244.46万只,平均规格为个体甲壳宽1.17cm、体重0.22g,平均成活率达到56.60％,单位面积出苗量为441.26只/m~2,取得较好的经济效益。 相似文献
10.
在全埋式无地沟无法吸污的育苗条件下,利用鲜活生物活饵料进行中华绒螯蟹(Eriocheur Sinensis)俗称河蟹的大棚育苗,配套生物饵料培养池50,000m2, 育苗水体1,680m3,平均每m3育苗水体培育出河蟹大眼幼体0.289kg。共育河蟹大眼幼体486kg,其中试验池为1,520m3水体;单位水体出苗量为0.314kg,对照池为160m3水体;单位水体出苗量为0.190kg。试验池比对照池每m3水体出苗量增产39.5%。 相似文献
11.
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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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
14.
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
15.
Controlled infection of Poecilia reticulata Peters (guppy) with Tetrahymena by immersion and intraperitoneal injection 
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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
16.
The endemic, anadromous cyprinidChalcalburnus tarichi is the only fish species known to occur in alkaline Lake Van (Eastern Anatolia, Turkey). EightC. tarichi were maintained individually in Lake Van water (17 – 19°C; pH 9.8; 153 mEq·I–1 total alkalinity; 22 total salinity) and tank water samples analyzed for 24 h in 2 to 4 h intervals. At zero time, < 1µM ammonia was present and urea was undetectable in the tank water; at 24 h, total ammonia and urea made up 114±32 and 35±25µM, respectively. Over the experimental period, ammonia-N and urea-N excretion averaged 1041±494 and 607±169moles·kg–1 fish·h–1, respectively. The extent of urea excretion was highly variable between specimens. Uric acid excretion was not detectable.Urea was present at high concentrations in all tissues and plasma (25 – 35moles·g–1·ml–1) of freshly caughtC. tarichi; total ammonia content of the tissues was by a factor of 1.9 (liver) to 3.0 (brain) lower. High arginase activity (2.4±0.2 U·min–1·g–1) was detected in the liver ofC. tarichi but ornithine carbamoylphosphate transferase, a key enzyme of the ornithine-urea-cycle, was absent. Ureagenesis is likely through degradation of arginine and/or uricolysis. High glutamine synthetase activity (11±0.6 U·min–1·g–1) and low ammonia content in brain suggest that, like other teleosts,C. tarichi has an efficient ammonia detoxification in the brain, but in no other tissue.Nitrogenous waste excretion at alkaline pH is discussed. The ability ofC. tarichi to excrete high levels of ammonia at extremely alkaline pH is unique among teleosts studied so far. The mechanism of ammonia excretion under Lake Van conditions remains to be elucidated. 相似文献
17.
There has been growing concern about the overuse of antibiotics in the ornamental fish industry and its possible effect on the increasing drug resistance in both commensal and pathogenic organisms in these fish. The aim of this study was to carry out an assessment of the diversity of bacteria, including pathogens, in ornamental fish species imported into North America and to assess their antibiotic resistance. Kidney samples were collected from 32 freshwater ornamental fish of various species, which arrived to an importing facility in Portland, Oregon from Colombia, Singapore and Florida. Sixty‐four unique bacterial colonies were isolated and identified by PCR using bacterial 16S primers and DNA sequencing. Multiple isolates were identified as bacteria with potential to cause disease in both fish and humans. The antibiotic resistance profile of each isolate was performed for nine different antibiotics. Among them, cefotaxime (16% resistance among isolates) was the antibiotic associated with more activity, while the least active was tetracycline (77% resistant). Knowing information about the diversity of bacteria in imported ornamental fish, as well as the resistance profiles for the bacteria will be useful in more effectively treating clinical infected fish, and also potential zoonoses in the future. 相似文献
18.
Effect of iodophor disinfection of non‐hardened Salmo trutta eggs on their bacterial and fungus load 下载免费PDF全文
下载免费PDF全文 Franz Lahnsteiner 《Aquaculture Research》2017,48(7):3901-3909
This study investigated the efficiency of iodophor disinfection (135 ppm active iodine for 15–30 min) of non‐hardened Salmo trutta eggs against different groups of bacteria and against fungus. Egg samples were taken from non‐disinfected and from disinfected eggs, microorganisms were cultured on specific nutrient media and their mass was measured by turbidimetric methods. Bacteria and fungus mass of non‐hardened eggs could be reduced but not eliminated by iodophor disinfection with 135 ppm active iodine for 15 min. The extent of reduction was 47–65% (Experiment 1). The efficiency of disinfection increased with disinfection time as the reduction in bacteria and fungus mass was 40–55% after 15 min and 58–74% after 30 min (Experiment 2). Disinfection efficiency of iodophor solution diluted in water (reduction 49–57%) and of iodophor solution diluted in sodium chloride solution iso‐osmolar to the oocytes (reduction 52–61%) was similar (Experiment 3). The reduction in bacteria and fungus mass was persistent as it was 39–72% lower in embryos deriving from disinfected eggs than in embryos deriving from non‐disinfected ones (Experiment 4). In conclusion, the tested disinfection method is inadequate to eliminate pathogens completely but it could positively influence immune defence of eggs and embryos. 相似文献
19.
T. Citarasu K. Venkatramalingam M. Micheal Babu R. Raja Jeya Sekar M. Petermarian 《Aquaculture International》2003,11(6):581-595
The indiscriminate use of antibiotics and chemicals in shrimp hatcheries has led to biomagnification and that in turn could
lead to rejection of a whole consignment. The application of the bioencapsulation technique as a tool for curative treatment
in shrimp larvae was investigated. Herbs having antibacterial properties such as Solanum trilobatum, Andrographis paniculata and Psoralea corylifolia (methanolic extracts) were bioencapsulated in Artemia and fed to Penaeus monodon post larvae PL 1–25. The post larvae were reared in a medium inoculated with pathogenic bacteria such as Pseudomonas aeruginosa, Staphylococcus aureus, Salmonella typhi and Vibrio sp. Post larvae reared in the non-inoculated water and fed with non-enriched Artemia exhibited 90% survival, highest specific growth rate (12.43%) and reduced bacterial load. P. monodon reared in the bacterial inoculated water and fed with the non-enriched Artemia exhibited the lowest survival (10–30%), specific growth rate (8.42–9.1%) and increased bacterial load (2.86 × 103 to 3.76 × 105 cfu/g). The methanolic extracts of the herbs helped to increase survival and specific growth rate and reduced bacterial load
in the P. monodon culture system. Among the three herbal extracts, P. corylifolia enriched Artemia fed post larvae showed the tendency to higher survival (>50%), growth rate (11.5 averaged) and low bacterial load (1.12 × 105 cfu/g).
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献