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。     

有水与无水保活运输对大菱鲆生理应激及鱼肉品质的影响

为探究大菱鲆分别在有水及无水条件下运输过程中生理生化指标及肌肉品质的变化,为大菱鲆的保活运输提供参考。将大菱鲆进行暂养、降温、充氧包装后进行模拟运输,并在运输不同时间段取样,检测大菱鲆生理生化指标及肌肉指标。结果显示,模拟运输18 h后,有水运输组和无水运输组中的大菱鲆存活率仍为100%。大菱鲆肌肉中水分含量、粗脂肪、pH、糖原、三磷酸腺苷(ATP)和腺苷酸(AMP)含量显著降低,乳酸和肌苷酸(IMP)含量升高。其中,有水运输组中的大菱鲆AMP含量降低了38.65%,IMP含量增加了29.1%,无水运输组中的大菱鲆AMP含量降低了12.83%,IMP含量增加了28.47%。大菱鲆血液生化指标中,葡萄糖、尿素氮和皮质醇含量显著升高。运输过程后,无水运输组中大菱鲆生理应激及能量代谢指标的变化幅度均小于有水运输处理组中的大菱鲆。此外,低温无水运输组大菱鲆肌肉中呈味核苷酸IMP和AMP含量显著高于有水运输组,表明低温无水运输增加了大菱鲆呈鲜味物质的含量,提高了鱼肉风味。研究表明,低温无水保活技术在活鱼运输中具有广泛的应用前景。     

Use of electromyogram telemetry to assess the behavioural and energetic responses of rainbow trout, Oncorhynchus mykiss (Walbaum) to transportation stress

Behavioural and energetic responses of domesticated rainbow trout Oncorhynchus mykiss (Walbaum) (mean fork length=440±45 mm) to a brief transportation episode were investigated. Fish implanted with radio transmitters measuring muscle activity (electromyogram; EMGi) were transported in a standard commercial shipping tank for 50 min by truck, and then allowed to recuperate for 48 h in stationary culture tanks. The EMGi telemetry data indicated that vigorous swimming activity occurred during transportation. Telemetry recordings also indicated that the fish's swimming activity returned to baseline levels within the 48 h period after transport. However, even beyond the 48 h resting period, the swimming performance (measured as critical speed and endurance) of transported fish was still impaired relative to non‐transported controls (P<0.05). Respirometry measurements of fish taken after transportation indicated that oxygen consumption (V_o2) was significantly elevated. The rise in V_o2 of post‐transport fish could be attributed to handling procedures, as well as the intense swimming behaviour observed during transportation. Therefore, the behavioural responses of fish during transportation produced physiological consequences that persisted long after the transportation event. This study demonstrates the potential for utilizing behavioural measures, in concert with biotelemetry technologies, as tools to assess the impacts of routine aquacultural procedures on the health and welfare of captive fish.     

Application of the consortia of nitrifying archaea and bacteria for fish transportation may be beneficial for fish trading and aquaculture

The growing popularity of the aquarium trade is greatly increasing the demand for many ornamental fish. While shipping technology has made the worldwide transportation of ornamental fish possible, a significant portion of the fish caught for the aquarium trade perish in transport before being sold to hobbyists. One of the major causes of fish death in transport is ammonia building up to toxic levels in the shipping bags. In order to solve this problem, we investigated the effectiveness of using nitrifying consortia in reducing the ammonia build‐up in marine fish bags during transport. A pre‐activated nitrifying consortium was effective in safely maintaining low ammonia levels during a three‐day experiment. We found that both ammonium chloride and urea can activate nitrifying consortia. Activation of nitrifiers by urea is not only novel but also beneficial due to being less harmful to fish in comparison with ammonia. We also discovered that unexpectedly one nitrifying consortium examined mainly contained ammonia‐oxidizing archaea. The confirmation of the concept of the use of activated nitrifying consortia and the usefulness of nitrifying archaea for fish transportation may be beneficial for the fish trading and aquaculture.     

Anaesthetics in the transport of mullet seed

This paper reports the results of an investigation on the use of anaesthetics in the transportation of live mullet seed. Experiments were carried out on thirteen anaesthetics to ascertain the dosages suitable for transportation of live-fish. These doses were further tested for the tolerance of mullet fry and fingerlings for a maximum period of 24 h. Metabolism experiments were performed to find out the degree of decrease in the metabolism in terms of active oxygen consumption. Finally, results are given of the trial consignment despatched by rail for a transport period of 20 h.The results indicate that out of the thirteen anaesthetics tried, seven were suitable for transportation of live fish. The relative merits and demerits of these anaesthetics are further discussed.     

鱼类保活运输技术研究现状及展望

安全高效的保活运输是保持鱼类鲜度的有效方式,既能满足消费者的需求,又可以提高企业的经济效益。介绍了有水运输和无水运输两种鱼类保活运输的技术方法,并对两种方法的优劣点进行了比较;阐述了鱼体体质、温度、水质(pH、溶氧、氨氮和代谢废物浓度)以及其他因素对鱼类运输存活率的影响;最后提出了现阶段鱼类保活运输存在的一些问题和应对措施,并对其发展前景进行了展望。根据对现有文献资料进行的分析,认为利用生态冰温法辅以二氧化碳作为麻醉剂进行无水运输将是今后鱼类保活运输研究和应用的重点。此外,开发无氧保活运输方法及相应的高效运输装备也应重点关注。这些都将有助于实现我国渔业现代化的更快发展。     

Recovery from transportation by road of farmed European eel (Anguilla anguilla)

The objective of this study was to assess the effects of transportation of marketable eel (0.15 kg) in the Netherlands with respect to welfare. Eels (Anguilla anguilla) were obtained from a commercial farm and acclimatized for 7 weeks at the laboratory. Fish were transported according to regular commercial procedures. The animals were placed in water‐filled transport tanks on the trailer. Fish density increased from 72 kg m^?3 (husbandry) to 206 kg m^?3 (fasting) and was further increased to 270–290 kg m^?3 during transport. Fish transport lasted 3 h after which the eels were returned to laboratory recirculation systems to measure parameters indicative of stress load, i.e. mortality, plasma cortisol, lactate and non‐esterified fatty acids (NEFA) as well as gill morphology. Samples were taken at 0, 6, 24, 48 and 72 h after transport in transported fish and non‐transported counterparts (controls). Transportation affected water quality within known tolerable limits. No mortality during or after transport was observed. After 6 h, plasma cortisol levels had returned to baseline. However, energy metabolism had increased suggesting that transportation of eels resulted in an increased energy demand that lasted for at least 72 h in the fasted animals. Thus, it is conceivable that exposure to adverse conditions, prior to stunning/killing, in a slaughterhouse may result in allostatic overload in eel.     

运输对养殖黄颡鱼血液生化和肌肉物性分析指标的影响

测定了在10.4~11.2℃下运输4 h后不同时间(0 h、1 h、3 h、6 h、12 h、1 d、3 d、7 d和20 d)养殖黄颡鱼(Pelteobagrus fulvidraco)血液生理生化指标和肌肉物性分析指标的变化。结果显示,运输引起了黄颡鱼血清皮质醇和血糖浓度的显著升高(P0.05),在运输结束12 h后恢复到正常水平。运输后鱼体血清超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性和总抗氧化能力(T-AOC)均有显著性升高,随着恢复时间的推移逐渐回降到正常水平;但过氧化物酶(POD)活性并未出现显著性差异,维持稳定的水平。运输后肌肉硬度、弹性、胶黏性、凝聚性、咀嚼性、回复性等物性分析指标均显著性降低。除了凝聚性和咀嚼性之外,其他肌肉物性分析指标在运输结束72 h后恢复到正常水平。研究表明,长途运输造成了养殖黄颡鱼的应激反应,对肌肉物性特征产生了显著的影响,但运输后的恢复可使鱼体抗氧化能力和肌肉物性分析指标回复到正常水平。     

Benefits of using the probiotic Efinol®L during transportation of cardinal tetra, Paracheirodon axelrodi (Schultz), in the Amazon

The objective of this experiment was to test the probiotic Efinol^®L during transportation of cardinal tetra, Paracheirodon axelrodi (Schultz). For the transportation, fish were distributed in 18 plastic tanks, of which nine contained the Efinol^®L (10 mg L⁻¹; probiotic treatment) and the remaining had no probiotic (control treatment). Transport lasted 24 h and three different boxes of each treatment were sampled at 3, 12 and 24 h. Up to the 12-h sampling period, no significant difference in the survival was observed; on the other hand, survival was higher at the end of the transport (24 h) in the probiotic treatment. No significant difference was found in dissolved oxygen and temperature between treatments. Conductivity, pH and alkalinity increased along the transport, but without a difference between treatments. Ammonia increased in all treatments, although it was significantly lower in the probiotic group at 24 h. Cortisol levels were significantly higher in all transported fish when compared with the basal values. At 24 h, cortisol levels in control fish were significantly higher than those in the probiotic treatment. With the observed results, we are able to conclude that the probiotic Efinol^®L is efficient during cardinal transport, lowering the mortality and helping maintain water quality possibly by lowering metabolic wastes.     

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.     

Using Efinol®L during transportation of marbled hatchetfish, Carnegiella strigata (Günther)

The objective of this experiment was to test the efficacy of a probiotic (Efinol^®L) during transportation of marbled hatchetfish, Carnegiella strigata . Wild specimens were captured from a small stream and transported for 24 h in plastic fish boxes with a probiotic (10 mg L⁻¹) and probiotic-free water. The boxes were sampled at 3, 12 and 24 h of transport. At the end of the experiment, the survival rate was close to 100% in both treatments. Dissolved oxygen diminished with time in both treatments, but the probiotic group had significantly higher levels. Conductivity, pH and ammonia increased significantly during the transport, demonstrating higher levels in the probiotic-free group. Fish from both treatments presented very high net Na⁺ and K⁺ effluxes after 3 h of transport. At 24 h, net K⁺ effluxes in fish of the probiotic treatment reached values close to zero and a significantly lower Na⁺ efflux was observed. Cortisol levels in both treatments at 3 and 12 h were significantly higher than that in control samples. Higher body cortisol levels were observed in the probiotic-free group than that in the probiotic group at 3 and 12 h. The results demonstrate that addition of a probiotic during fish transport improves water quality and leads to fish presenting a lower stress response intensity.     

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.     

Salt as a stress response mitigator of matrinxã, Brycon cephalus (Günther), during transport

The present study evaluated the physiological responses of matrinxã, Brycon cephalus (Günther) submitted to transport stress under the influence of sodium chloride. Different salt concentrations (0.0%, 0.1%, 0.3% and 0.6%) were added to four 200-L plastic tanks. Each tank was stocked with 30 fish (mean weight 1.0 ± 0.2 kg) and transported for 4 h. Blood was sampled prior to transport and immediately after and 24 and 96 h after transport. Plasma cortisol and glucose and serum sodium and potassium, plasma chloride and ammonia were analysed. Changes in plasma cortisol were observed immediately after transportation, except in fish transported in 0.3% and 0.6% salt. Twenty-four hours later, this hormone had returned to its initial level in all fish. Blood glucose was not changed in fish treated with 0.6% salt immediately after transport, and returned to the initial level within 96 h after the other treatments. All treatments resulted in lower levels of plasma chloride after transport, except for fish treated with 0.6% salt, with fish treated with 0.0% and 0.3% salt recovering 24 h later. Serum sodium decreased immediately after transport only in the control fish, returning to the initial level 24 h later. The results indicate that treatment with 0.6% NaCl reduces most of the physiological responses of matrinxã to the stress of transport.     

Transportation and handling stress of white suckers raised in cages

Changes in plasma cortisol concentrations were measured in juvenile white suckers, Catostomus commersoni (Lacepede), as a measure of their response to transportation (8 h) and chase challenge stressors. The study attempted to evaluate the ability of this species to withstand standard aquacultural husbandry practices. Plasma cortisol concentrations were elevated during and following transportation. Recovery from transportation (as plasma cortisol levels reached baseline values) was prolonged in fish transported under winter conditions compared with fish transported during the summer months. The plasma cortisol response to a 5 min chase challenge in well-fed juvenile white suckers was typically of 2 to 3 h periodicity with the peak values between 15 and 30 min. This pattern was similar in fish fed three commercial diets (although rates of recovery differed), and was unaffected by fasting. The return of plasma cortisol concentrations to baseline values following the chase-challenge stressor was prolonged in fasted groups. The results of this study showed that juvenile white suckers require several days to recover from transportation and under the acclimation conditions applied, the recovery was faster in the fish transported during the summer.     

Effects of Temperature Reduction and MS‐222 on Water Quality and Blood Biochemistry in Simulated Transport Experiment of Largemouth Bronze Gudgeon,Coreius guichenoti

The effects of temperature reduction, MS‐222 (3‐aminobenzoic acid ethyl ester methanesulfonate) anesthesia and the combination of these factors on water quality and the blood biochemistry of the largemouth bronze gudgeon, Coreius guichenoti, a rare, endangered, and valuable fish in the upper Yangtze River, were investigated before and after simulated long‐term transport. The results showed that transport caused deterioration of water quality and elevated the concentrations of plasma cortisol (2–3.5 times) and plasma lactate (1.33–2.5 times) in C. guichenoti. Temperature reduction was found to play a major role in improving the water quality by reducing total ammonia nitrogen and oxygen consumption, while MS‐222 anesthesia mainly inhibited the activity of transported C. guichenoti and suppressed the increases in plasma lactate and alanine aminotransferase. Some interactions were observed between anesthesia and temperature reduction during C. guichenoti transportation regarding improving the water quality and reducing the physiological stress. The results suggest that during the long‐term transportation of C. guichenoti, the combined use of temperature reduction and MS‐222 is most preferable, followed by the use of temperature reduction alone or MS‐222 at a relatively high temperature. These data provide useful information regarding the transport and physiological response of C. guichenoti as well as other related stresses in this fish.     

Effect of Handling and Transport on Cortisol Response and Nutrient Mobilization of Golden Shiner,Notemigonus crysoleucas

As the most popular baitfish in the USA, the golden shiner is subjected to frequent handling and transportation episodes prior to retail marketing and recreational use. Considerable mortality and economic loss can occur during handling and transportation. Limited information is available concerning stress responses, such as cortisol secretion, and mobilization of nutrients, such as zinc and ascorbic acid, during handling and transportation of this fish species. Therefore, two concurrent experiments were performed to characterize cortisol responses, as well as changes in whole‐body zinc and visceral ascorbic acid concentrations, after harvesting, grading, and transporting by ground or air. During ground transportation, fish were sampled immediately after being subjected to the following conditions: seined from a commercial pond in Lonoke, Arkansas (I), released into vats from the loading truck (II), graded by bar grader (III), loaded onto a hauling truck (IV) and after transport for 10 h to Brenham, Texas (V). Fish were also sampled before and after air freight shipment. Whole‐body cortisol appeared to be a reliable endocrine marker for stress response of golden shiner subjected to handling and transportation. Grading by bar grader was the most stressful event in the process of handling and transporting golden shiners, resulting in a significantly elevated whole‐body cortisol concentration of 107 ng/g tissue, compared to concentrations of 6.3, 32.3, 15.7, and 30.4 ng/g tissue, for stages I, II, IV, and V, respectively. A significant increase in whole‐body cortisol concentration was also observed after air transportation of 22 h duration. No significant reductions in whole‐body zinc or visceral ascorbic acid concentrations were observed.     

Curcuma longa supplementation in the diet of Astyanax aff. bimaculatus in preparation for transport

The physiological state of fish before transportation is an important aspect to be observed when reduction in losses due to mortality is aimed. Various preparative procedures for transport are reported, but little is known about the use of additives in fish diet. In this study, we aimed to evaluate the effect of dietary turmeric (Curcuma longa) supplementation on the tolerance of juvenile Astyanax aff. bimaculatus to transportation stress. The experimental design consisted of six treatments: 0, 20, 40, 60, 80 and 100.0 g kg^?1 turmeric. Fish weighing 0.83 ± 0.04 g were distributed in 24 80‐L aquaria at a density of 0.5 fish L^?1 and were fed to satiation three times a day for 60 days. After this period, fish were transported for 24 h in plastic bags (15 fish per bag). Using a discontinuous linear response plateau (LRP) model, the lowest estimated concentration of turmeric that maximized the survival rate was 16.67 g kg^?1. Quadratic effects of turmeric on blood lactate levels were observed, and the estimated concentration of turmeric required to minimize blood lactate levels was 64.7 g kg^?1. We observed quadratic effects of turmeric on superoxide dismutase activity and the concentration of malondialdehyde in fish gills and the turmeric concentrations required to minimize the transport stress effects on these variables were 42.50 and 83.33 g kg^?1, respectively. Thus, dietary supplementation with turmeric enhanced the tolerance of juvenile A. aff. bimaculatus to transportation stress.     

Stress in African catfish (Clarias gariepinus) following overland transportation

Of the many stressors in aquaculture, transportation of fish has remained poorly studied. The objective of this study was therefore to assess the effects of a (simulated) commercial transportation on stress physiology of market-size African catfish (Clarias gariepinus). Catfish weighing approximately 1.25 kg were returned to the farm after 3 h of truck-transportation, and stress-related parameters were measured for up to 72 h following return. Recovery from transportation was assessed through blood samples measuring plasma cortisol, glucose and non-esterified fatty acids (NEFA) and gill histology. Also, the number of skin lesions was compared before and after transport. Pre-transport handling and sorting elevated plasma cortisol levels compared to unhandled animals (before fasting). Plasma cortisol levels were further increased due to transportation. In control fish, plasma cortisol levels returned to baseline values within 6 h, whereas it took 48 h to reach baseline values in transported catfish. Plasma glucose and NEFA levels remained stable and were similar across all groups. Transported catfish did not, on average, have more skin lesions than the handling group, but the number of skin lesions had increased compared to unhandled animals. The macroscopic condition of the gills was similar in control, transported and unhandled catfish; however, light microscopy and immunohistochemistry revealed atypical morphology and chloride cell migration normally associated with adverse water conditions. From our data, we conclude that transportation may be considered a strong stressor to catfish that may add to other stressors and thus inflict upon the welfare of the fish.     

MS-222对鳊鱼麻醉保活运输效果的研究

为研究MS-222对鳊鱼保活运输的影响,分析比较了在不同质量浓度MS-222(0、20、40、60、80、100 mg/L和120 mg/L)、不同水温(2、7、15、20℃)和不同鱼水质量比(2∶1、1∶1、1∶3、1∶5)下鳊鱼的存活率,从而确定及筛选最佳的保活运输条件,并检测和分析在保活运输试验中水质指标和鱼体生化指标的变化和影响。试验结果显示,当MS-222质量浓度为60 mg/L、水温7℃、鱼水比1∶3时,保活时间最长,鱼体存活率最高;随着保活时间的延长,水体指标中氨氮含量、微生物、pH均呈上升趋势,而溶解氧水平则呈下降趋势;在鱼体指标中,肌肉中糖原、pH下降,乳酸含量上升;在血液指标中乳酸脱氢酶、谷草转氨酶、血糖、尿素和肌酐均显著增加(P<0.05),说明随着保活时间的延长,鱼体肝脏和肾脏组织代谢水平受到一定的影响,但其变化幅度均小于对照组。研究结果表明,在鳊鱼保活过程中可适当使用MS-222麻醉剂以延长存活时间和提高存活率。     

脂肪酸营养对鱼类生长、脂代谢及免疫性能影响的研究进展

脂肪酸在鱼类营养中起着重要的作用，脂肪酸作为能源物质为鱼类的生长发育等各项活动提供能量，并协助脂溶性维生素的吸收和体内运输。不同鱼类因其生活环境不同，对必需脂肪酸的需求种类也不同。由于不同脂肪水平与不同脂肪酸来源的饲料因其脂肪酸含量或脂肪酸组成不同，不同鱼类或鱼类的不同生长阶段对脂肪源的利用也不同，那么饲料的脂肪水平或脂肪酸组成不同就对鱼类的生长、脂代谢及免疫性能产生一定的影响作用。必需脂肪酸作为鱼类重要的脂肪酸营养物质同样影响鱼类的生长、脂代谢及免疫性能。本文从脂肪酸营养对鱼类生长、脂代谢及免疫性能的影响等方面进行综述，并对今后的研究重点进行了展望。’