中国沿海常见棘毒鱼类的毒性研究──日本鬼鲉棘毒液对螫伤大鼠局部组织结构及代谢的影响

于１９９６—１９９７年春、秋渔汛季节,在山东青岛、日照沿海采集日本鬼鲉,分离毒腺,提取毒腺粗提液,对大鼠后肢进行肌肉注射,采用组织学、组织化学、放射免疫学方法观察和检测局部皮肤和肌肉的组织结构改变、注射局部肌细胞内的琥珀酸脱氢酶（ＳＤＨ）及神经肌肉连接处的已酰胆碱酯酶（ＡｃｈＥ）活性变化以及神经肽──Ｐ物质和生长抑素含量的改变。结果表明,毒腺粗提液局部注射可造成大鼠肢体麻痹;局部皮肤和肌肉组织明显肿胀,肌细胞有损伤,其内ＳＤＨ活性显著降低,肌细胞及其间质水肿、血管扩张、伴有出血现象;神经肌肉连接处ＡｃｈＥ活性显著增强;局部肌肉组织中Ｐ物质含量显著升高,而生长抑素含量显著降低。提示毒棘螫伤造成的剧烈疼痛和肿胀可能与Ｐ物质有关,造成肢体麻痹可能与肌细胞损伤及神经肌肉接头处乙酰胆碱分解过程增强有关。     

Distribution of sea cucumbers in relation to sediment characteristics in coral reef lagoons and adjacent waters around Ishigaki Island,southern Japan

To elucidate which environmental factors affect lagoonal‐scale sea cucumber distributions in Ishigaki Island, Okinawa, Japan, intertidal and subtidal areas of three coral reef lagoons were classified into several ground divisions by bottom characteristics, and sea cucumber densities therein were compared with the composition of sediment cover, grain size and organic content, and coverage of macroalgae, seagrass, and massive corals. Holothuria atra, Holothuria leucospilota, Stichopus chloronotus, and Synapta maculata had highest densities in the nearshore areas but were rare in reef flats, probably because of wave disturbance and low areal cover of sand sediment as potential feeding environments. No relationship was observed between sea cucumber densities and sediment organic content or grain size. Thus, even if these sea cucumbers have selectivity for habitats with a high sediment organic content, the effect of such selectivity on the distribution seems to be limited to relatively small areas. The sea cucumber distributions can be classified by bottom sediment/biota composition into bedrock (H. leucospilota), sand (H. atra), and lagoonal types (St. chloronotus and Sy. maculata). These habitat selections were possibly related to various aspects of sea cucumber ecology such as refuge from predators or turbulence, or settlement and nursery place, which have implications for importance of the complexity of lagoonal‐scale topography and sediment/biota conditions for the coexistence of various holothurian species.     

Genetic variation in two sea cucumber （Apostichopus japonicus） stocks revealed by ISSR markers

Sea cucumber Apostichopus japonicus samples were collected in Changdao, Penglai (PL), 27 individuals, and Lingshandao, Qingdao (QD), 30 individuals, in the Shandong Peninsula, China. Ten SSR primers were used to assess the genetic variation and relationship between and within the two stocks. Respectively, for each stock, the percentage of polymorphic bands was 85.2% and 86.9%; the gene diver- sity was 0.360 5 and 0.342 8; and the Shannon’s information index was 0.515 0 and 0.499 0. At species level, the percentage of polymorphic bands was 92.2%, the total gene diversity was 0.378 9 and the Shannon’s information index was 0.550 4. The coefficient of overall genetic differentiation and the ge- netic distances between the stocks were also calculated to be 0.073 0 and 0.079 6 using the POPGENE program. Results show that the genetic diversity of the two stocks is still large but the genetic distance between the two stocks is close. A dendrogram was constructed for the 57 individuals from the two stocks, showing that the genetic structure was unitary for PL stock but complex for QD stock.     

Growth, metabolism and physiological response of the sea cucumber, Apostichopus japonicus Selenka during periods of inactivity

The growth, metabolism and physiological response of the sea cucumber, Apostichopus japonicus, were investigated during periods of inactivity. The body weight, oxygen consumption rate (OCR), activities of acidic phosphatase (ACP), alkaline phosphatase (AKP), catalase (CAT) and superoxide dismutase (SOD), and content of heat shock protein 70 (Hsp70) in the body wall and coelomic fluid of A. japonicus were measured during starvation, experimental aestivation and aestivation. The results showed that the body weight of sea cucumber in the three treatments decreased significantly during the experimental period (P < 0.05). The OCR of sea cucumber reduced in starvation and experimental aestivation treatments, but increased gradually in natural aestivation treatment. The activities of ACP and AKP of sea cucumber decreased gradually in all treatments, whereas those of SOD and CAT as well as Hsp70 content decreased in the starvation and experimental aestivation treatments and increased in natural aestivation treatment. The sea cucumber entered a state of aestivation at 24℃. To some extent, the animals in experimental aestivation were different from those in natural aestivation in metabolism and physiological response. These findings suggested that the aestivation mechanism of A. japonicus is complex and may not be attributed to the elevated temperature only.     

菲对日本虎斑猛水蚤摄食、生长发育和繁殖的影响

为探究多环芳烃(Polycyclic aromatic hydrocarbons,PAHs)污染对海洋桡足类的毒性效应,本研究以日本虎斑猛水蚤(Tigriopus japonicus)为受试生物,选取菲(Phenanthrene,Phe)作为PAHs的代表开展暴露试验.急性毒性试验测得Phe对日本虎斑猛水蚤的96 h半...     

Effects of Pseudoalteromonas sp.BC228 on Digestive Enzyme Activity and Immune Response of Juvenile Sea Cucumber （Apostichopus japonicus）

A marine bacterium,Pseudoalteromonas sp.BC228 was supplemented to feed in a feeding experiment aiming to determine its ability of enhancing the digestive enzyme activity and immune response of juvenile Apostichopusjaponicus.Sea cucumber individuals were fed with the diets containing 0 （control）,105,107 and 109 CFU g-1 diet of BC228 for 45 days.Results showed that intestinal trypsin and lipase activities were significantly enhanced by 107 and 109 CFU g-1 diet of BC228 in comparison with control （P〈0.01）.The phagocytic activity in the coelomocytes of sea cucumber fed the diet supplemented with 107 CFUg-1 diet of BC228 was significantly higher than that of those fed control diet （P〈0.05）.In addition,105 and 107 CFUg-1 diet of BC228 significantly enhanced lysozyme and phenoloxidase activities in the coelomic fluid of sea cucumber,respectively,in comparison with other diets （P 〈 0.01）.Sea cucumbers,10 each diet,were challenged with Vibrio splendidus NB 13 after 45 days of feeding.It was found that the cumulative incidence and mortality of sea cucumber fed with BC228 containing diets were lower than those of animals fed control diet.Our findings evidenced that BC228 supplemented in diets improved the digestive enzyme activity of juvenile sea cucumber,stimulated its immune response and enhanced its resistance to the infection of V.splendidus.     

Effects of water depth and substrate color on the growth and body color of the red sea cucumber,Apostichopus japonicus

Three color variants of the sea cucumber,Apostichopus japonicus are recognized,the red one is highly valued in the market. When the red variant is cultured in ponds in China,its body color changes from red to celadon in 3–6 months. The effects of water depth and substrate color on the growth and body color of this animal were investigated. Juveniles of red A. japonicus were cultured in cages suspended at a range of water depths(20,50,100,150 and 200 cm). The specific growth rate of red sea cucumbers was significantly higher in animals cultured at deeper water layers compared with those grown at shallowers. Body weights were greatest for sea cucumbers cultured at a depth of 150 cm and their survival rates were highest at a depth of 200 cm. A scale to evaluate the color of red sea cucumbers(R value) was developed using a Pantone standard color card. All stocked animals in the 9-month trial retained a red color,however the red body color was much more intense in sea cucumbers cultured at shallower depths,while animals suspended in deeper layers became pale. In a separate trial,A. japonicus were cultured in suspended cages with seven different colored substrates. Substrate color had a significant effect on the growth and body-color of red A. japonicus. The yield were greatest for A. japonicus cultured on a yellow substrate,followed by green white orange red black and blue. All sea cucumbers in the 7-month trial retained a red color,although the red was most intense(highest R value) in animals cultured on a blue substrate and pale(lowest R value) for animals cultured on a green substrate.     

Effects of photoperiod on daily activity rhythm of juvenile sea cucumber, Apostichopus japonicus (Selenka)

In nature, Apostichopus japonicus exhibits a behavioral characteristic of emerging at night and sheltering during the day. Hence, it was commonly believed that longer and darker light conditions are better for a population of A. japonicus. In aquaculture situations therefore, animals have commonly been cultured without lighting, especially during juvenile-hatching culture. However, how the length of darkness each day affects A. japonicus and what the mechanism is of behavioral response of A. japonicus to different photoperiods remain unclear, and are specifically addressed in this study. We applied nine photoperiod treatments (light:dark (LD) cycles at 0:24, 3:21, 6:18, 9:15, 12:12, 15:9, 18:6, 21:3, and 24:0 under 500 lx) to 60 individuals (29.73 ± 0.23 g) per treatment (with 3 replicates). The environmental conditions were set as: water temperature = 16.9 ± 0.3°C, dissolved oxygen>6.0 mg/L, ammonia<0.3 mg/L, pH = 7.8-8.2, and salinity = 30-32. Under experimental conditions of continuous darkness as well as continuous light, cyclic nocturnal activity patterns of A. japonicus (viz. the animals emerged and fed at night and sheltered during the day) were observed. However, they spent more and less time, respectively, moving and feeding under continuous darkness and continuous light, than those under a natural light cycle. Under photoperiods with 6-12 h of light, the animals showed one sheltering behavior transition and two emerging behavior transitions. These behavior transitions appeared to be governed by some internal physiological factors and induced by daily light variation. The behavior of the animals was significantly affected by different photoperiods, and the distribution rate (DR) of the animals emerging at "daytime" increased with lengthening "light time" (except for the LD 3:21 cycle). We also found that there was no significant difference in mean DR per day under LD cycles of 6:18, 9:15, 15:9, and 12:12. Mean DRs per day were significantly lower for these photoperiods, than for those under LD cycles of 0:24 and 3:21, and significantly higher than for those under LD cycles of 18:6, 21:3 and 24:0. These results imply that 6-15 h light per day were the similar photoperiods to natural sunlight. From the viewpoint of activity and feeding behaviors, these might be the optimal photoperiods for rearing A. japonicus.     

海洋酸化对日本虎斑猛水蚤发育、繁殖以及ATP酶活性的影响

大气中二氧化碳浓度增加造成海洋酸化并改变海洋化学环境,可能对海洋生物造成不利影响。桡足类是海洋生态系统中重要的次级生产者,研究桡足类如何应对海洋酸化的影响对海洋生态风险评估具有重要作用。本文分别在自然海水(pH 8.1,对照)和二氧化碳酸化海水(pH 7.3)条件下培养日本虎斑猛水蚤(Tigriopus japonicus Mori,1938),研究海水酸化对其发育、繁殖以及ATP酶活性的影响效应。结果显示,海水酸化能使日本虎斑猛水蚤无节幼体发育时间显著延长并使雌体产生的无节幼体数量显著减少,Na^+/K^+-ATP酶和Ca²⁺-ATP酶活性在酸化条件下均显著增强。研究结果表明,海水酸化胁迫下日本虎斑猛水蚤能量消耗增加,应用于发育和繁殖的能量可能减少,从而引起早期幼体发育延滞和雌体繁殖力下降的负面反应。     

渤海鲈鱼食物组成与摄食习性的研究

对渤海３５３尾鲈鱼的胃含物样品进行了分析，得出如下结论：（１）鲈鱼为游泳动物食性的鱼类，游泳动物占其胃含物总重量的６３．５８％；（２）主要摄食鱼类，甲壳类，其饵料种类主要包括口虾蛄，Ｔｉ鱼，凤鲚，黄鲫等；（３）食物组成与摄食习性呈现明显的月变化；（４）幼鲈主要摄食小型鱼类，甲壳类及其幼体，在相应月份里，与成鲈的食物组成相似程度很小。