Effects of linalool on physiological responses of Cyprinus carpio (Linnaeus, 1758) and water physico‐chemical parameters during transportation

This study investigated the potential of linalool as an anaesthetic during transportation of common carp, Cyprinus carpio. The fish were transported at a loading density of ~103 g/L for 3 hr in 12 plastic bags (3 L water and 6 L pure oxygen) divided into four triplicated treatments: control (without linalool), L50 (50 mg linalool/L), L100 (100 mg linalool/L) and L200 (200 mg linalool/L). After 3‐hr transportation, serum physiological responses and water physico‐chemical parameters were compared among the treatments. Results showed that water total and un‐ionized ammonia increased and dissolved oxygen decreased in all treatments after transportation. Water total ammonia and dissolved oxygen levels in the linalool‐treated bags were significantly lower than the control. After transportation, the control fish showed significant elevation in serum cortisol and glucose levels; however, the levels were significantly lower than the linalool‐treated fish. All fish showed similar serum lactate levels, significantly lower than the value obtained before transportation. The control fish showed serum urea levels similar to the level obtained before transportation; however, the linalool‐treated fish had significantly higher serum urea levels compared to the control and before transportation levels. After transportation, all fish had decreased serum chloride and sodium levels compared to the before transport level. Overall, the present results showed that linalool is not beneficial for carp transportation in plastic bags, because it reacts with water oxygen, increases stress in fish, interferes with ammonia excretion and has no benefits in preventing ion loss.     

国内外海水观赏鱼产业与研究现状

海水观赏鱼贸易是海洋水族馆贸易行业的重要部分,是一项价值十几亿美元的产业,每年交易量达数百万尾,且需求量逐年上升,但由于严重依赖野生资源捕捞而使该行业饱受争议。目前,90%~95%的海水观赏鱼由野生捕捞获得,在已知的数千种珊瑚礁鱼类中,有一半以上在缺乏或无监测情况下进行贸易,自然资源面临严重威胁。观赏性水产从业者和消费者有责任保护野生捕获物种的可持续发展,海水观赏鱼的养殖被认为是一种保护野生资源的有效手段,但仍有许多技术问题阻碍其发展。文章结合相关数据和文献,概述了国际海水观赏鱼产业现状及最新研究进展,讨论了海水观赏鱼产业中存在的问题,并提出了一些可行的解决方案,旨在为中国海水观赏鱼产业发展提供一定的借鉴和参考。     

Freshwater fishes of Southeast Asia: potential for the aquarium fish trade and conservation issues

SoutheastAsia is an area rich in biodiversity, with a high degree ofendemism in both flora and fauna. Many freshwater fish specieshave been exploited for the ornamental fish trade. As thepopulation in South East Asia increases, vast tracts of forestsare cleared for agricultural, industrial and urbanizationpurposes. To conserve and sustainably exploit the wild fishpopulation, measures should be adopted to protect this naturalresource. Already, several ornamental species have been severelyoverexploited, e.g. bala shark (Balantiocheilos melanopterus),pygmy loach (Botia sidthimunki) and arowana (Scleropagesformosus), but the extirpation of local populations occurs formany reasons, including deforestation, and not just because offishing for the trade. There are also still many species thathave great ornamental fish potential. Wild fish species have alsobeen successfully bred in captivity and conserved, e.g. tigerbarb (Puntius tetrazona), bala shark, pygmy loach and arowana.Other methods of conservation include public education, leavingpristine forests intact and reforestation. The aquarium trade ofthe bala shark, harlequin rasbora (Rasbora heteromorpha), clownloach (Botia macracanthus), arowana and sawfish (Pristismicrodon) is discussed     

The Potential for the Restoration of Marine Ornamental Fish Populations Through Hatchery Releases

Populations of tropical and subtropical marine fish are being depleted worldwide to supply increasing demands of the aquarium industry and fresh seafood market. Overfishing and destructive harvest techniques have left some marine fish populations virtually extirpated in a number of primarily underdeveloped countries. In situations where only small remnant populations and significantly degraded habitat remain, population recovery even under the complete absence of collection will be slow, with the high potential for population loss due to natural environmental and recruitment variability. Stock enhancement, supplementing natural recruitment with hatchery produced fry, has the potential to significantly increase the rate of population recovery while maintaining population vigor.Stock enhancement research on Pacific threadfin has demonstrated measurable positive impacts on recreational and commercial fisheries for this species in experimental scale releases; similar successes can be expected for enhancement efforts directed toward species of ornamental value. The major technological barrier to ornamental fish enhancement, the development of appropriate culture capabilities, is being addressed in research directed to the commercial production of fish for the aquarium trade.     

New perspectives on aquarium fish trade

ABSTRACT:   Since the 1990s, the international market for importing aquarium fish is suspicious of stock coming from South-East Asia. Fish catches are still executed with cyanide-based toxic products. In the present paper, the potential of the French Polynesian Islands to develop a marine aquarium fish business with a new approach is explored. Coral reef fish are captured at the larval stage with crest nets, then larvae are reared in aquaria before being put on the world ornamental fish market. This approach offers several advantages: (i) larvae are captured with a passive system placed on the reef crest (crest net) that does not destroy the environment and limits the stress on collected larvae; (ii) larvae are then put into farmed basins that allow them to be controlled sanitarily; and (iii) larvae are weaned at the farm and fed rapidly with artificial food. This method increases survival rates as it eliminates the food acclimatization problem of fish captured at adult stage (main cause of fish mortality in aquaria). Overall, reared larvae will constitute a new product in terms of species, sizes and quality of ornamental fish on the aquarium market.     

Survival and serum biochemical responses of spotted sea bass Lateolabrax maculatus during simulated waterless live transportation

Waterless live fish transportation is an alternative and promising transport strategy, which may reduce shipping costs, increase stocking density and improve survival of some species. Spotted sea bass is one of the most economically important marine fish in China. However, waterless transportation has not yet been studied on spotted sea bass. To explore the possibility of waterless transportation of spotted sea bass and its sublethal stress responses, the survival rate and dynamics of blood biochemical parameters were evaluated in the present study by preserving it under no water, less water and water (control) conditions for 9 hr. The serum biochemical parameters including total protein, cortisol, glucose, lactate, alanine aminotransferase (ALT), aspartate aminotransferase (AST), total carbon dioxide (TCO₂), creatinine, blood urea nitrogen (BUN), ammonia, superoxide dismutase (SOD) activity and malonaldehyde (MDA) were investigated. Results showed that the survival rates of fish in all groups gradually declined with time increasing. At the end of transportation, the survival rates in the control group, less‐water group and no‐water group decreased to 49.11%, 15.60% and 23.96% respectively. Significant changes were observed in several selected serum biochemical parameters, including glucose, lactate, ALT, TCO₂, BUN and ammonia during simulated waterless transportation, which might negatively affect the physiological homeostasis of fish, leading to the high mortality in present study. In general, waterless transportation of spotted sea bass was possible, but it might be rather suitable for short time than long time.     

Relationship between body weight and loading densities in fish transport using the plastic bag method

Abstract. The transportation of live fish in sealed plastic bags was examined. Water parameters and loading densities were analysed. Based on several assumptions an estimation of oxygen consumption during transport was performed indicating that metabolism during transport was about three times higher than routine metabolism. There was some evidence that small fish were more affected by transportation stress, and that large fish need a longer starvation time before transport to reduce ammonia excretion sufficiently.     

Investigation of ornamental fish entering the EU for the presence of ranaviruses

A survey was performed on ornamental fish imported into the EU to detect viral agents belonging to the genus Ranavirus. The objective was to gain knowledge of the potential for these systemic iridoviruses to gain entry into the EU via international trade in ornamental fish. A total of 208 pooled samples, representing 753 individual fish, were tested. The samples included 13 orders and 37 families, originating from different countries and continents. Tissues from fish that died during or just after transport were collected and examined by standard virological techniques in epithelioma papulosum cyprini cells, by transmission electron microscopy and by PCR for the detection of the major capsid protein and DNA polymerase gene sequences of ranaviruses. Virus was isolated from nine fish species but ranavirus was not identified in those samples. The results suggest that ranaviruses are not highly prevalent in ornamental fish imported into the EU.     

Recent developments and improvements in ornamental fish packaging systems for air transport

Current ornamental fish packaging systems are characterized by very high fish loading densities and high metabolic wastes in the transport water after shipment. They focus mainly on management of the quality of transport water. Recent studies using the guppy as a model fish showed that post‐shipment mortality could be reduced through enhancement of the stress resistance of the fish, and hence emphases should also be placed on the preparation of the fish for transport and recovery of the fish after shipment. Farmers can contribute significantly by applying nutritional prophylaxis before harvesting. Exporters may use the salinity stress test to identify fish lots of good quality for transport, apply health prophylaxis to eradicate parasites and optimize other techniques such as starvation of the fish or addition of salt to the transport water to enhance the stress resistance of the fish. Importers may adopt proper acclimation procedure and allow fish to recover in low salinity water to reduce post‐shipment mortality. As the main bulk of post‐shipment mortality is stress‐mediated and occurs during the 1‐week recovery period, the industry should consider revising the basis of the current warranty system for their customers, from death on arrival to cumulative mortality at 7 days post shipment (or death after 7 days, DA7), in order to cut down fish losses after shipment.     

Stringed bed suspended bioreactors (SBSBR) for in situ nitrification in penaeid and non-penaeid hatchery systems

For establishing nitrification in prawn (non-penaeid, salinity 10–15 ppt) and shrimp (penaeid, salinity 30–35 ppt) larval production systems, a stringed bed suspended bioreactor (SBSBR) was designed, fabricated, and validated. It was fabricated with 5 mm polystyrene and low density polyethylene beads as the substrata for ammonia and nitrite oxidizing bacterial consortia, respectively, with an overall surface area of 684 cm². The reactors were activated in a prototype activator and were transported in polythene bags to the site of testing. Performance of the reactors activated with the nitrifying bacterial consortia AMONPCU-1 (ammonia oxidizers for non-penaeid culture) and NIONPCU-1 (nitrite oxidizers for non-penaeid culture) was evaluated in a Macrobrachium rosenbergii larval rearing system and those activated with AMOPCU-1 (ammonia oxidizers for penaeid culture) and NIOPCU-1 (nitrite oxidizers for penaeid culture) in a Penaeus monodon seed production system. Rapid setting up of nitrification could be observed in both the static systems which resulted in a higher relative per cent survival of larvae.     

Structure and Management Issues of the Emerging Ornamental Fish Trade In Eritrea

Following independence from Ethiopia in 1993, Eritrea resumed exploiting Red Sea and Arabian fish species for the ornamental trade in 1995 as a means to earn foreign exchange from sparsely exploited marine resources. This paper describes the findings of research conducted in 1997, in collaboration with the Eritrean Ministry of Fisheries. The capture, transport and export of aquarium fish were reviewed and potential impacts and the status of management were investigated through liaison with stakeholders and researchers. From 1995 to 1997 two companies exported approximately 60,000 fish per year, mainly to the USA, worth US$65,000 (export value). Seventy-five species (from 22 families) were exported. Damselfishes made up two-thirds of total exports but more valuable families (angelfishes and butterflyfishes) were more economically significant. To earn revenue for Eritrea, a 20% export tax was imposed, although this was calculated from declarations by the operators. The emerging nature of the trade allowed detailed monitoring by the Ministry of Fisheries. However, management efforts were constrained by a lack of capacity for enforcement and baseline research. Several potential effects of the trade exist but other, land-based impacts may be more pressing concerns for Eritrea's reefs. Research priorities for management are discussed as well as the implications of mariculture of Eritrean species by other nations.     

Profile of the Marine Aquarium Fish Trade in Hong Kong

A market survey and review of government statistics were carried out to establish imports and exports of marine ornamental fishes into and out of Hong Kong, and to examine the local trade in terms of volume, value and species composition. Official government import figures for marine aquarium fishes were available from 1984 to 1991 and from 1997 and 1998. When compared with net imports, export and re-export volumes over the 15-year period were small, indicating that most imports entered the local market, or were exported unrecorded. The market survey of marine aquarium shops in Hong Kong was carried out between August 1996 and January 1997. From this survey, an annual estimate of 957,563 coral reef fish was calculated for the local trade, valued at HK$57,453,780, with a mean retail price of HK$60 per fish. These figures account for an estimated 2–3% of the global value and volume of marine aquarium fish trade, according to 1992 figures and, compared with government figures, indicate that official declarations of imports are underreported by at least 2–3 fold. A total of 342 marine aquarium fish species, from 49 families, were recorded with about 60% belonging to the families Labridae, Chaetodontidae, Pomacanthidae and Pomacentridae. It was estimated that a large proportion of the trade was in juvenile fishes and almost all fish were less than 10cm in standard length. It was common to see fishes in poor condition, species hard to maintain in captivity, or those listed for conservation concern, on sale. There are no regulations for local traders of live marine fishes other than those relating to either protected species or animal welfare. Licensing of traders in marine fishes could be introduced under existing Hong Kong legislation if fishes were to be re-classified as animals. This is strongly recommended as a step towards regulating and managing the trade in Hong Kong.     

Comparative efficacy of MS-222 and benzocaine as anaesthetics under simulated transport conditions of a tropical ornamental fish Puntius filamentosus (Valenciennes)

There is a growing commercial interest in the fish, Puntius filamentosus , in the ornamental fish trade in India and elsewhere. The trade is, however, hampered by severe mortalities during transport of the fish owing to insufficient data available on the use of anaesthetics. To resolve this problem, we evaluated the efficacy of two anaesthetics, MS-222 and benzocaine, in sedating P. filamentosus in simulated transportation experiments and used stress response parameters such as cortisol and blood glucose levels to perform assessments. We observed that MS-222 at 40 mg L⁻¹ and benzocaine at 20 mg L⁻¹ were sufficient to induce sedation for 48 h. Above these concentrations, both the anaesthetics adversely affected the fish and resulted in mortalities. Both anaesthetics significantly lowered the blood cortisol and glucose levels compared with the unsedated controls. Importantly, the anaesthetics treatment significantly lowered the post-transport mortality in the fish. The results of the study show that MS-222 and benzocaine could be used as sedatives to alleviate transport-related stress in P. filamentosus to improve their post-transport survival and hence reduce economic loss.     

Occurrence of Mycobacterium spp. in ornamental fish in Italy

The occurrence of Mycobacterium spp. in freshwater and marine ornamental fish was studied in Italy from June 2002 to May 2005. Two surveys were carried out, one of aquarium fish sent to the Laboratory for diagnosis, and the other of prevalence of infection by mycobacteria in ornamental fish imported into Italy. Bacterial isolation was carried out from the spleen, kidney and liver, and the isolates were subsequently identified by biochemical tests. In the first survey, 387 fish were examined and Mycobacterium spp. were isolated from 181 (46.8%) fish. In the second survey 127 batches of ornamental fish from different countries were examined. Mycobacterium spp. were isolated from 38 (29.9%) batches. The following species were found: M. fortuitum, M. peregrinum, M. chelonae, M. abscessus, M. marinum, M. gordonae, M. nonchromogenicum and M. interjectum. There was a high prevalence of infection independent of the presence of macroscopic lesions. Mycobacterium fortuitum and M. chelonae were more prevalent than M. marinum in the samples examined.     

Effect of unmanaged harvests for the aquarium trade on the population status and dynamics of redline torpedo barb: A threatened aquatic flagship

相似文献   

Ornamental Fish Industry in Sri Lanka: Present Status and Future Trends

The aquarium fish industry in Sri Lanka has become a valuable foreign exchange earner during the past few years, earning Rs. 530 million in 1998. Sri Lankan ornamental fish exports for the international market include locally wild caught marine, brackish-water and freshwater species as well as captive bred freshwater fish. Presently, there are about 18 registered aquarium fish exporters and together they currently contribute approximately 1% of the world's demand for ornamental fish. Of the freshwater fish species exported from Sri Lanka, the guppy ranks the highest (67% by number), followed by swordtails, angels, platies and various species of tetras. This study aims to assess the present status and future trends in the ornamental fish industry in Sri Lanka; to overview the present fish production system which caters for the international market; and to identify present constraints within the industry. This revised version was published online in August 2006 with corrections to the Cover Date.     

A quantitative method for detecting ammonia‐oxidizing bacteria in coastal aquaculture systems

There is a need to quantify autotrophic nitrifiers in coastal aquaculture systems for evolving a bioremediation strategy. Autotrophic nitrifiers are extremely slow‐growing organisms, which cannot be detected by traditional methods as they are notoriously difficult to culture. Molecular techniques based on functional genes could be deployed for the detection of nitrifiers. Ammonia monooxygenase (amoA), that catalyses the oxidation of ammonia to hydroxylamine in the rate‐determining step of nitrification is largely unique to ammonia‐oxidizing bacteria (AOB). In the present study, a quantitative real‐time polymerase chain reaction assay targeting amoA was developed to estimate AOB population size in coastal soil, ammonia‐removing bioaugmentors and the solid matrix. To achieve this objective, different set of primers and a dual labelled probe have been designed for SYBR Green and TaqMan real‐time assays. The abundance of AOB ranged from 10⁴ to 10⁶ order of magnitude in the samples. In the present study, biofilm formation of the consortium of nitrifying bacteria onto bagasse has also been quantified. The results demonstrate that the developed method is a rapid and sensitive tool for the quantitative detection of nitrifying bacteria in aquatic and related environment. This helps in making the bioremediation approach for ammonia removal by immobilization of nitrifying bacteria onto the natural substrate.     

新加坡观赏鱼产业发展的机遇与挑战

新加坡是一个小岛国,农业用地及用于养鱼的海域面积均很有限。但新加坡观赏鱼产业相当独特和成功,是世界第一观赏鱼出口国,向80多个国家出售超过1 000种鱼类,2016年的年收入达到4 300万美元。该产业的成功主要源于其在许可证颁发,生物安全控制,养殖,包装,运输和疾病控制等各方面所具有的独特特征。新加坡正在努力驯养和培育许多高价值的海洋物种和新的淡水物种,并开发新型的循环水养殖系统。上游研究侧重于开发和使用基因组工具来培育新品种并维持野外种类的遗传多样性。但由于养殖鱼类的空间有限,邻国竞争激烈,该行业面临诸多挑战,其市场份额正在减少。在这篇综述中,我们将总结新加坡观赏鱼产业的现状和发展,讨论其面临的挑战,并提出保持该产业领先地位的建议。     

Marine ornamental fish imports in the European Union: an economic perspective

The marine ornamental fish trade (MOFT) is a worldwide industry that targets a remarkable quantity and diversity of reef fish species and provides an important source of revenue for exporting countries, particularly developing nations in Southeast Asia. Here we provide, for the first time, an economic assessment of the MOFT to the European Union (EU), one of the key players of the marine aquarium trade, along with the USA and Japan. Data from EUROSTAT (the European Statistical System) was analysed for the MOFT between 2000 and 2011. Results show that this industry was not affected by the economic crisis and accounted for a total of 135 million Euros during the study period. Both the UK and Indonesia have been reinforcing their importance as leading importer and exporter countries, respectively. The long‐term temporal pattern of the MOFT by EU and non‐EU countries is described, as well as its diversity and evenness between importing and exporting countries. The present economic assessment also identifies the key players of this industry, and ultimately contributes to management and conservation practices that may enhance the sustainable use of world's coral reefs.     

鱼贝类生态冰温无水活运研究进展

随着市场对鲜活鱼贝类需求的加剧,保活运输技术的研究成为热点。低温可使鱼贝类呼吸减弱、新陈代谢降低,进入"冬眠"状态,便于无水保活运输。鱼贝类生态冰温无水活运的关键工艺包括生态冰温的确定、梯度降温、贮运环境、唤醒。本文主要介绍了生态冰温原理、技术特点以及一些关键工艺方法,分析了鱼贝类生态冰温无水活运过程中需要注意的技术点,如鱼贝类品类、运输装备及运输途中各环节的有机衔接等,并对已有生态冰温无水活运技术进行了总结,指出该技术未来研究趋势及方向,为优化、完善鱼贝类生态冰温无水活运体系研究提供参考。