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1.
随着海参增养殖业的发展,对海参苗的需求量也在不断增加。目前,海参养殖的苗种来源是通过工厂化育苗来提供,而工厂化育苗的生态环境比较稳定,同时也就保护了弱势群体,人为地减少了海参苗的自然淘汰,在这种条件下繁育的海参苗,成活率比较高,但是,把在这种条件下繁育的海参苗投放到自然环境中养殖,成活率偏低,只有5%~15%。  相似文献   

2.
我国海参池塘养殖存在的问题及应对措施   总被引:1,自引:0,他引:1  
进入21世纪我国在经历了以海带、对虾、扇贝、海洋鱼类为代表的四次海水养殖浪潮之后,海水养殖业迎来了以海参为代表的第五次浪潮。目前我国海水养殖业正朝着多品种、多元化的可持续方向发展,海参养殖已发展成为我国海水养殖业中的一个重要产业。近年来,随着海参养殖业的高速发展,出现了多种海参养殖方式:围堰养殖、池塘养殖、网箱养殖、室内工厂化养  相似文献   

3.
近年来,海参育苗与养殖在北方地区发展很快,育苗场不断增多,有关育苗技术也得到了深入的研究,笔者在2006年海参工厂化育苗过程中使用了稳定性一元二氧化氯,对育苗池水进行消毒杀菌处理,取得了较好的效果,培育出的海参苗规格整齐,体质健壮,生长较快,用户购买后反映良好。  相似文献   

4.
<正>随着经济的发展和人们生活水平的提高,对海参的需求量越来越大。自然产的海参越来越少,人工养殖得到了空前的发展。尤其是近年来,养殖企业和养殖户越来越多地尝试工厂化养殖,克服现有养海参方式的缺点和弊病,完善海参养殖工艺,降低海参养殖成本,缩短海参养殖周期,以推进海参养殖业的快速发展。  相似文献   

5.
近日,江苏省赣榆县青口镇榆城集团刺参工厂化人工育苗获得成功,填补了江苏省刺参工厂化人工育苗的空白。目前,青口镇拥有刺参育苗水体3万米3,年销售额可达1700多万元。2009年以来,榆城集团与连云港市海洋与渔业局,赣榆县海洋与渔业局共同承担了刺参工厂化人工育苗项目。为引导好这一产业的发展,科研人员从苗种、水质和管理三大方面加大管理力度,严格加强海参关键技术和新模式研发,健全海参养殖病害防治体系。  相似文献   

6.
近年来,棘皮动物养殖业得到了迅速发展,尤其是海胆、海参这两个商业品种,不仅满足了国内消费者的需要,还出口国外。但是随着棘皮动物养殖快速发展,人工育苗规模不断扩大,病害问题频繁发生造成巨大的经济损失,如海参的烂皮病、海胆的黑嘴病等,在一定程度上阻碍了养殖业的健康稳定发展。  相似文献   

7.
南方工厂化鲍参混养试验   总被引:1,自引:0,他引:1  
正红刺参具有生长速度较快、抗病能力强、较耐高温、体壁厚、胶原蛋白、粘多糖等营养物质丰富等特点,经济价值为刺参的2~3倍。随着红刺参繁殖驯化的成功,成功打破了海参增养殖的海区限制,将海参增养殖海域扩展到南方海域,利用南方冬春季进行海参养殖能有效避免海参冬眠现象,缩短了海参的生长周期。另一方面,由于近年来鲍鱼养殖业的畸形扩张导致了鲍鱼养殖业饱受病害困扰,养殖成功率急剧下降,工厂化养殖更甚,如何优化  相似文献   

8.
近年来,沿海地区海参养殖业蓬勃发展,但随着养殖规模的不断扩大,海参养殖中存在的问题日益凸现。从2004年水产养殖病害测报中可以看出,海参病害以2月份~4月份最为严重,7月份~9月份趋于平缓,进入12月份以来又有爆发迹象。海参病害的发生对海参养殖业产生了一定冲击,影响了海参养殖业健康、有序的发展。笔者结合生产实际谈以下几点看法:一、海参养殖中存在的问题1.苗种问题全人工育苗成功解决了海参养殖的苗种数量问题,但随之而来的苗种质量问题一直困扰着广大养殖者。育苗生产不规范,造成苗种质量下降,直接影响了海参养殖生产的全过程。2.环…  相似文献   

9.
张丽敏 《河北渔业》2012,(11):44-45
<正>昌黎县拥有64.9km海岸线,浅海及滩涂资源丰富。近年来,昌黎县以渔业增效、渔民增收为核心,以养殖结构调整为主线,进一步实现由规模渔业向生态效益渔业、由传统渔业向现代渔业的转变,重点发展了浅海筏式扇贝养殖、滩涂养殖、工厂化养殖和人工渔礁养殖等,特色水产品有扇贝、海参、对虾、河鲀、牙鲆、大菱鲆、半滑舌鳎等。随着浅海养殖业的兴起,水产品加工、育苗、销售  相似文献   

10.
海参饲料研究的现状与发展方向   总被引:15,自引:0,他引:15  
袁成玉 《水产科学》2005,24(12):54-56
自20世纪80年代以来,随着海参人工育苗与养殖产业的迅速发展,海参用饲料研究越来越受到业内人士的关注。海参用饲料的好坏,直接影响海参育苗与养殖生产的成败。特别在目前,苗种生产与成参养殖迅速发展,海参用饲料需求量不断增加,而原料又十分短缺、饲料市场比较混乱,海参饲料开始成为限制海参苗种与养殖生产业发展的潜在因素。为此,笔者将综合叙述海参用饲料研究的发展过程、现状,并探讨其存在的问题以及今后发展的方向,供广大从事海参研究、教学、生产者参考。1海参用饲料的发展过程1.1国外海参饲料的研究工作始于刺参人工育苗方面的研究,…  相似文献   

11.
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   

12.
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   

13.
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   

14.
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   

15.
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   

16.
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   

17.
The sea raven, Hemitripterus americanus, is a sit-and-wait, low metabolic rate, marine teleost. The objective of this study was to determine i) whether cortisol implantation (50 mg. kg-1) for 7 days altered hepatocyte metabolism, and hepatocyte responsiveness to epinephrine, glucagon and insulin, and ii) whether 8 weeks of food-deprivation modified the above response. Cortisol implantation significantly increased hepatocyte total glucose production and oxidation from alanine compared to the sham group. There was no cortisol effect on glycogen breakdown, suggesting that the activation of other pathways, including gluconeogenesis, are required to account for the increased glucose production. Epinephrine-mediated (10-5M) glycogen breakdown and insulin-mediated (10-8M) total glucose production were enhanced in hepatocytes of cortisol implanted sea ravens, but there were no change in any glucagon (10-7M) effects. The enhanced glycogen breakdown in the absence of similar increases in total glucose production with epinephrine indicates mobilization of carbohydrate reserves for endogenous use by the liver. Food-deprivation for 8 weeks significantly decreased condition factor, plasma cortisol concentration and liver glycogen content in the sea raven, but had no effect on plasma glucose concentration. Hepatocyte total glucose production and flux rates from alanine increased significantly with food-deprivation. Moreover, food-deprivation increased responsiveness of total hepatocyte glucose production to the actions of glucagon and insulin, but not to epinephrine; none of these effects were modified by cortisol implantation. Our results indicate that cortisol in the sea raven exerts both a direct and an indirect or permissive effect on hepatocyte metabolism by modifying hepatocyte responsiveness to epinephrine and insulin stimulation. Cortisol implantation did not modify the effects of glucagon or food-deprivation in this species.  相似文献   

18.
Important environmental processes for the survival and recruitment of early life stages of pelagic fishes have been synthesized through Bakun's fundamental triad as enrichment, concentration and retention processes (A. Bakun, 1996, Patterns in the Ocean. Ocean Processes and Marine Population Dynamics. San Diego, CA, USA: University of California Sea Grant). This conceptual framework states that from favourable spawning habitats, eggs and larvae would be transported to and/or retained in places where food originating from enrichment areas would be concentrated. We propose a method for quantifying two of the triad processes, enrichment and retention, based on the Lagrangian tracking of particles transported within water velocity fields generated by a three‐dimensional hydrodynamic model. We apply this method to the southern Benguela upwelling ecosystem, constructing putative maps of enrichment and retention. We comment on these maps regarding main features of the circulation in the region, and investigate seasonal variability of the processes. We finally discuss the results in relation to available knowledge on the reproductive strategies of two pelagic clupeoid species abundant in the southern Benguela, anchovy (Engraulis encrasicolus) and sardine (Sardinops sagax). Our approach is intended to be sufficiently generic so as to allow its application to other upwelling systems.  相似文献   

19.
This study evaluated the effects of three levels of loading density (200, 300 and 400 g L−1) and four levels of duration (1, 3, 6 and 9 h) on the mortality, plasma cortisol and chloride levels and growth of rohu Labeo rohita fingerlings in a transport simulation. While total immediate mortality was low (4–12%), delayed mortality was high (27–49%). Initial capture and handling were found to constitute the most stressful phase as indicated by elevated plasma cortisol. The levels of cortisol continued to rise at 6 and 9 h after transport, with the highest level observed at 9 h after transport. The level of plasma chloride fell after transport across all density levels and treatment durations. Specific growth rate (SGR, %/day) and total bacterial density (cfu/g) were not different between and within treatments, and between treatments and the controls. This study demonstrates that transport has a profound effect on the stress responses of rohu fingerlings. Although the level of immediate mortality was low, the higher level of delayed mortality has serious implications in terms of production inefficiency for grow-out farmers.  相似文献   

20.
  • 1. The common name ‘tilapia’ refers to a group of tropical freshwater fish in the family Cichlidae (Oreochromis, Tilapia, and Sarotherodon spp.) that are indigenous to Africa and the southwestern Middle East. Since the 1930s, tilapias have been intentionally dispersed worldwide for the biological control of aquatic weeds and insects, as baitfish for certain capture fisheries, for aquaria, and as a food fish. They have most recently been promoted as an important source of protein that could provide food security for developing countries without the environmental problems associated with terrestrial agriculture. In addition, market demand for tilapia in developed countries such as the United States is growing rapidly.
  • 2. Tilapias are well‐suited to aquaculture because they are highly prolific and tolerant to a range of environmental conditions. They have come to be known as the ‘aquatic chicken’ because of their potential as an affordable, high‐yield source of protein that can be easily raised in a range of environments — from subsistence or ‘backyard’ units to intensive fish hatcheries. In some countries, particularly in Asia, nearly all of the introduced tilapias produced are consumed domestically; tilapias have contributed to basic food security for such societies.
  • 3. This review indicates that tilapia species are highly invasive and exist under feral conditions in every nation in which they have been cultured or introduced. Thus, the authors have concluded that, despite potential or observed benefits to human society, tilapia aquaculture and open‐water introductions cannot continue unchecked without further exacerbating damage to native fish species and biodiversity. Recommendations include restricting tilapia culture to carefully managed, contained ponds, although exclusion is preferred when it is feasible. Research into culture of indigenous species is also recommended.
Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

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