额尔齐斯河湖拟鲤寄生虫季节动态及其优势虫种的寄生情况调查研究

按照鱼类寄生虫的常规调查及研究方法,对额尔齐斯河(中国段)湖拟鲤(Rutilus rutilus lacustris Pallas)寄生虫的种类、感染情况、季节动态及优势寄生虫种的寄生情况进行调查。结果共发现6种寄生虫,分别为维氏指环虫(Dactylogyrus vistulae Prost)、西伯利亚副双身虫(Paradiplozoon homoion homoion Bychowsky et Nagibina)、双穴吸虫幼虫(Diplostomum sp.)、绦虫幼虫(Cestode sp.larva)、对盲囊线虫(Contracaecum sp.)和椭圆尾鲺(Ar-gulus ellipticaudatus Wang),隶属于3门,5纲,6目,6科,6属。春、夏、秋三季,均发现双穴吸虫幼虫,夏季及秋季的感染率高于春季;维氏指环虫春季的感染率高于夏季,而秋季没有检出;西伯利亚副双身虫、对盲囊线虫、绦虫幼虫和椭圆尾鲺仅在夏季发现,且感染率及感染强度均不高。     

Fixed location hydroacoustic monitoring of fish populations in the tidal River Hull, north-east England, in relation to water quality

Abstract  Fixed location hydroacoustic fish monitoring was carried out at a series of sites in the tidal River Hull, north-east England, in July 1996 during periods of moderate freshwater flows and spring tides. This was followed by a corresponding series during a period of lower freshwater flows and spring tides in autumn 1996. The surveys indicated substantial numbers of fish living upstream and downstream of a depleted oxygen zone which exists in the tidal Hull. Conditions in this zone of poor water quality deteriorated further during low flow periods due to reduced dilution of effluents. Fish populations moved with the tide apparently in response to gradients of dissolved oxygen and salinity. Under conditions of low freshwater flow and high tides, gradients of salinity and oxygen were steeper and fish responses appeared more marked: at higher salinities, the response to increasing salinity overrode the response to decreasing oxygen availability.     

Complete developmental cycle of Myxobolus pseudodispar (Gorbunova) (Myxosporea: Myxobolidae)

Myxobolus pseudodispar (Gorbunova) is a common parasite of the muscle of roach, Rutilus rutilus L., whereas its actinosporean development occurs in two oligochaete alternate hosts. This paper reports the complete developmental cycle of this parasite in the oligochaete alternate host Tubifex tubifex and the roach. In laboratory experiments, parasite-free T. tubifex specimens were infected by myxospores of M. pseudodispar collected from roach in Lake Balaton. Parasite-free roach fingerlings were infected with floating triactinospores (TAMs) released from oligochaetes on day 69 after challenge. Young plasmodia and spores in roach were first recorded on day 80 post-exposure (p.e.). Myxospores collected from experimentally infected roach initiated a new development in T. tubifex and the resulting TAMs infected roach. No infection of roach resulted from feeding oligochaetes containing mature triactinospores.     

Effects of Different Dietary Lipid Sources on Growth Performance,Salinity Tolerance,Haematological and Biochemical Parameters of Caspian Roach (Rutilus rutilus caspicus) Juvenile

This study investigates the effects of replacing fish oil with two vegetable oils (Sunflower oil and Soybean oil) on growth performance, salinity tolerance, hematological and serum biochemical profile of Rutilus rutilus over 56 days. Five diets were supplemented with 8% of either fish oil (FO) (control), sunflower oil (SFO), and soybean oil (SO) or a combination of 4% FO with 4% SFO and 4% FO with 4% SO, respectively. Triplicate groups of fish (24 fish per tank with an average body weight, of 5.52 g) were assigned to each diet. Blood samples were taken from the caudal vein of 75 apparently healthy fish at the end of trial. Hematological values of the blood samples were determined using standard techniques. At the end of the experiment fish were exposed to salinity stress. The results showed that the best growth performance was in fish fed the control diet, but the differences were minor among treatments containing vegetable oils (P > 0.05). Serum cholesterol and glucose concentrations were significantly higher in fish fed dieta containing vegetable oils (P < 0.05). Red blood cell count (RBC), hematocrit (Ht) and hemoglobin (Hb) in groups fed diets containing SFO and SO were higher than other groups (P < 0.05). There was no significant difference in survival after 48 h salinity stress (P > 0.05). These results indicate that in cases where fish oil is scarce or expensive, vegetable lipids can be used as replacements without any serious negative growth performance and health impacts.     

Influence of photoperiod and temperature manipulation on gonadal development and spawning in Caspian roach (Rutilus rutilus caspicus): Implications for artificial propagation

Caspian roach (Rutilus rutilus caspicus), a spring spawning teleost, were subjected to various photoperiod and temperature regimes to study the feasibility of shifting the timing of spawning for artificial propagation purposes. A total of 650 female reproductively mature R. rutilus caspicus were subjected to different photoperiod and temperature regimes including four light regimes (natural light (NL), 16 hr of light (L):8 hr of darkness (D), 9L:15D, 11L:13D), each affected by three temperature regimes (14, 20 and 24°C) for 70 days. Five fish per tank were randomly sampled on Feb. 10, Feb. 20, March 28, April 15 and April 30 (natural spawning time). Ovarian tissue sections were studied using light microscope and transmission electron microscope (TEM). The levels of 17‐β estradiol (E2) and 17α‐hydroxyprogesterone (OHP) were also measured in the serum samples. In late winter (March 28th), the gonadal maturation and spawning were accelerated in fish treated with the long day length (16L/8D) and warm temperature (20°C). While, the maturation of oocytes and spawning delayed in fish exposed to low temperature (14°C) and short day length (9L/15D and 11L/13D). Photoperiod seems to play a more important role in the ovarian development of the R. rutilus caspicus compared to temperature; since even among the fish treated with the lowest temperature (14°C), those exposed to a longer day length (16L/8D), matured and spawned earlier than the others. Considering that the earliest spawning occurred in R. rutilus caspicus treated with 16L/8D at 20°C and the latest spawning occurred in fish exposed to low temperature and short photoperiod, it can be concluded that temperature and photoperiod play an important role in accelerating oocyte maturation and spawning.     

北京山区油松林地菌根性食用菌发生规律

 【目的】明确北京油松林地菌根性食用菌的发生规律以及与林地的依存状况,为松林的持续发展和野生菌的合理开发利用提供理论依据。【方法】对北京山区油松林地发生的菌根食用菌种类、发生时间、发生量与立地条件等进行4年的定位观测和临时调查。【结果】血红铆钉菇（Chroogomphus rutilus）和点柄粘盖牛肝菌(Suillus granulatus)是油松林地最常发生的2种外生菌根菌,其次为棕灰口蘑(Tricholoma terreum）。 点柄粘盖牛肝菌和血红铆钉菇分布于海拔400—1 100 m,于8—10月发生,多雨年份出菇达到4—5潮,持续时间可达2个月以上。其子实体发生后约5 d散发孢子,天热时 7 d后腐烂。点柄粘盖牛肝菌在春秋雨水较多的年份还发生于夏初和深秋。充足降雨之后,连续3—5 d的高温是子实体大量发生的必要条件。油松林地地下菌塘菌丝密集,地表具有丰富的生物多样性。【结论】血红铆钉菇、点柄粘盖牛肝菌是北京油松林地的优势菌根性食用菌。降雨量、温度等气象因子是决定每年子实体发生时间和当年产量高低的重要因子。不同海拔、不同坡位的油松林地,菌根食用菌发生时间、发生的优势种类不同。     

Genetic variation of Rutilus rutilus caspicus (Jakowlew 1870) populations in Iran based on random amplified polymorphic DNA markers: a preliminary study

Rutilus rutilus caspicus is regarded as a valuable fish species both for angling and commercial food in Iran. This fish is also considered as a significant food source for beluga sturgeon. The genetic diversity of this fish species collected from two geographical areas (Gorgan Bay and Anzali Wetland) along the Iranian coastline of the Caspian Sea was examined using the analysis of randomly amplified polymorphic DNA (RAPD). Using 10 decamer primers, the total number of RAPD bands produced in both Gorgan Bay and Anzali Wetland populations were 94 bands. The percentages of polymorphic bands were comparable in Anzali Wetland (41.48%) and Gorgan Bay (43.61%), suggesting similar levels of polymorphism of the two populations to be used for establishing selective breeding programmes. The value of Nei's genetic distance (d=0.04) among populations was small, despite the large geographic separation. The data serve as a baseline analysis of current genetic diversity found among R. rutilus caspicus populations in Iran.     

血红铆钉菇子实体中化学成分类型及多糖含量

利用中药材的系统预试验方法对血红铆钉菇(Chroogomphus rutilus)子实体所含主要化学成分类型进行鉴定.结果表明,该菇中含有氨基酸、蛋白质、多糖、内酯、香豆素、酚类、甾类、萜类和脂肪族化合物.血红铆钉菇子实体水提醇沉后的粗多糖得率为6.34％,多糖含量约为子实体干重的4.60％.     

血红铆钉菇子实体对人肝星状细胞LX-2和人肝癌细胞Hep G2增殖的影响

[目的]探讨血红铆钉菇子实体对人肝癌细胞HepG2和人肝星状细胞LX-2增殖的影响,筛选出血红铆钉菇子实体抗肝纤维化和抗肿瘤作用的活性部位。[方法]利用天然药物化学方法提取得到血红铆钉菇子实体的石油醚、二氯甲烷、乙酸乙酯、正丁醇、水和粗多糖提取物,应用MTT法观察血红铆钉菇子实体不同溶剂提取物对体外培养的人肝星状细胞LX-2和人肝癌细胞Hep G2增殖的抑制作用,通过倒置显微镜观察细胞的形态学变化。[结果]血红铆钉菇子实体石油醚、二氯甲烷和乙酸乙酯提取物均对人肝星状细胞LX-2和人肝癌细胞Hep G2具有抑制增殖作用,显微镜观察结果表明,均可改变LX-2细胞和Hep G2细胞的形态。[结论]石油醚、二氯甲烷和乙酸乙酯提取物是血红铆钉菇子实体抗肝纤维化和抗肿瘤作用的主要活性部位。     

Predation risk from piscivorous fish influencing the diel use of macrophytes by planktivorous fish in experimental ponds

Abstract— This study investigated interactions between zooplanktivores (roach and perch) and piscivorcs (pike and large perch) in experimental ponds (16 m²) with open water habitat and three densities of natural macrophytes. Fish habitat selection was determined both day and night and was supported by daytime observations to study anti-predator behavioural patterns. Diel migration out from among macrophytes was seen in the absence of predators, particularly for roach, which changed from 13% of individuals being in open water during the day to 90% at night. The risk of predation from piscivores influenced the habitat selection of the zooplanktivores. Roach seemed to be the most vulnerable to predation from pike and selected the open water (90-92%) during daylight hours, but kept a 1-m distance from the macrophytes edge. The presence of pike thus reduced the use of macrophytes by roach, which in turn may improve macrophytes and the edge area as a refuge for zooplankton. Pike appeared to have less impact on the gross habitat selection of O+ perch, which were associated with the macrophytes (58–89%), though they were still vulnerable to predation. Adult perch, which was a generally less effective predator than pike, showed subdued behavior, concealing them selves in the macrophytes most of the time. No effect of the simultaneous presence of two predator species was found.