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1.
阿鲁加姆锡兰蛭(Zeylanicobdella arugamensis)是重要的鱼类体外寄生虫,可感染30余种海水鱼类。阿鲁加姆锡兰蛭病在我国和东南亚多个国家的海水养殖鱼类中流行,严重时可导致鱼类大量死亡。为持续、稳定、足量地获得活体寄生虫,供防治鱼蛭病研究使用,本研究通过鱼蛭在体感染实验,建立了阿鲁加姆锡兰蛭的传代培养体系。研究结果证实,2种海水观赏鱼[棘颊雀鲷(Premnas biaculeatus)和白条双锯鱼(Amphiprion frenatus)]可作为宿主鱼,用于该鱼蛭的传代培养,且传9代后产生的子代仍具有很强的感染力。鱼蛭的生活史观察显示,该鱼蛭的生活史可分为卵茧孵化和幼蛭发育2个阶段。在水温为26℃、盐度为30的条件下,鱼蛭最短20 d即可完成其生活史。其中,卵茧孵化为幼蛭需要9 d,孵化率高达83.8%;幼蛭感染宿主、发育成熟并开始产卵茧最短需要11 d。本研究可为海水鱼蛭的生物学和鱼蛭病的防治研究提供技术支撑。  相似文献   

2.
比较有机孵化基质对宽体金线蛭卵茧孵化效果和不同开口饵料对苗种生长发育的影响。孵化基质分别为土壤、牛粪有机肥、蘑菇菌渣,开口饵料分别为螺蛳、漂螺。试验结果显示,蘑菇菌渣+土壤组卵茧孵化率高达98.89%,显著高于土壤组和蘑菇菌渣组(P<0.05);幼蛭各生长指标显著高于土壤组、蘑菇菌渣组、有机肥组及有机肥+土壤组(P<0.05);混合组幼蛭各生长指标均显著高于未添加土壤组(P<0.05)。5种不同孵化基质孵化率依次为蘑菇菌渣+土壤>土壤>有机肥+土壤>有机肥>蘑菇菌渣。不同开口饵料的试验比较发现,漂螺组幼蛭成活率为72.50%,显著高于螺蛳组和螺蛳+漂螺组(P<0.05),漂螺组和螺蛳+漂螺组幼蛭体质量显著高于螺蛳组(P<0.05)。生长效果依次为漂螺组>螺蛳+漂螺组>螺蛳组。试验结果表明,蘑菇菌渣可以作为宽体金线蛭卵茧孵化基质;无厣结构的漂螺更适宜作宽体金线蛭幼蛭的开口饵料。  相似文献   

3.
一种吻蛭类大鱼蛭在大菱鲆鱼体上的感染   总被引:5,自引:1,他引:5  
在山东省威海崮山育苗场发现大菱鲆成鱼及幼鱼鱼体感染寄生虫,受感染的鱼由于处于感染初期,并经过及时的处理,所占比例较低。病鱼症状为鱼体体色变黑、瘦弱、离群、不摄食甚至死亡。寄生虫寄生于大菱鲆的体表及鳃部,虫体黑褐色,全长40~50mm。经鉴定,该寄生虫属于环节动物门(Annelida),蛭纲(Hirudinea),吻蛭目(Rhynochobdellida Blanchard),鱼蛭科(Piscicolidae Johnson),鱼蛭属(Piscicola Blainville),大鱼蛭(Pisciola magna Yang)。  相似文献   

4.
张涛  于翔  龚元  宋文华  李军  张健  赵晓临  杜华  王旭  卫航 《鲑鳟渔业》2014,(2):52-55,60
在土壤温度为24℃~26℃下,采用网箱湿土养殖法对具有生殖环带的宽体金线蛭(Whitmania pigra)进行了繁殖试验,统计了水蛭减重率、成活率和产茧率。在室内温度为26℃~28℃下,采用水箱孵化法孵化宽体金线蛭所产的卵茧,统计卵茧孵化率。结果表明:产茧后的宽体金线蛭平均减重率和成活率分别为43.5±1.41%和87.5±6.36%;宽体金线蛭平均产茧量和卵茧孵化率分别为1.22±0.04枚/条和73.1±0.57%。  相似文献   

5.
《水产科技情报》2000,27(1):36-37
八、鱼蛭鱼蛭俗称土虫或黑虫,是石斑鱼养殖中偶尔见到的一种外寄生虫。淡水、海水中均有分布。海水性品种较少。1.病因鱼蛭类似于陆栖的水蛭,体扁平细长,长约2~5cm,具环节,能游泳运动。体躯前后各具一个吸盘,前吸盘较小,由口部周围肌肉形成,用来吸附于宿主以吸食血液...  相似文献   

6.
正宽体金线蛭卵茧孵化出苗1~2 d后开口摄食,摄食方式是将头部钻入幼螺体内吸食汁液。因宽体金线蛭苗特殊的形态和运动方式,其苗种培育方式与鱼苗不同。目前主要采用聚乙烯网布制作育苗箱,因其体积小,环境易污染及换水次数频繁等原因,蛭苗易发生应激反应而死亡,且苗种培育过程中网箱壁遇水后易发生大范围逃苗。营造适合水蛭苗种生长的养殖环境和易于收集苗种的育苗设施是宽体金线蛭苗种培育成功的关键。在2015—2017年实施江苏省水产三新工程"宽体金线蛭高效养殖及苗种繁育技术集成与示范"项目过程中,对宽体金线蛭苗种培育技术做了一些探讨。  相似文献   

7.
鱼蛭病     
《海洋与渔业》2014,(1):62-62
<正>病原尺蠖鱼蛭。临床症状寄生在鱼的体表、鳃、鳍条等处,病鱼烦躁不安,在水面狂游,严重寄生时导致生长不良及贫血。流行情况可危害黄鳝、鲫鱼、草鱼等鱼,夏秋季感染较多。诊断根据症状在易感部位发现虫体即可确诊。防治措施1.蛭类对食盐敏感,每立方米水体可用20~25kg食盐浸洗1小时。2.0.7ppm敌百虫全塘泼洒,连用两次。海洋渔业  相似文献   

8.
为研究宽体金线蛭的人工繁殖技术,以野外采捕的宽体金线蛭成体作试验材料进行室外繁殖和室内孵化试验,统计其产茧量、空茧数、孵化率。试验结果:约5 000 kg种蛭共产卵茧351.5 kg;当种蛭投入产茧床时的土壤湿度为60 %时,产茧量达到最大值;当孵化箱的土壤湿度为40 %时,空茧数显著低于湿度为20 %、50 %、70 %的组(P<0.05),孵化率显著高于湿度20 %、50 %、70 %组(P<0.05),空茧数、孵化率与湿度30 %组差异不显著(P>0.05)。结果表明:宽体金线蛭人工繁殖采用室外繁殖、室内孵化的方案可行。当投入产茧床时,60 %的土壤湿度有利于种蛭钻进土壤中产茧,显著提高种蛭的产茧量。孵化箱的土壤湿度控制在30 %~40 %时,孵化率最高。  相似文献   

9.
温度和密度对日本医蛭繁殖的影响   总被引:1,自引:0,他引:1  
在实验室网箱中,研究温度(24±1)℃和(20±1℃)与密度(200尾/箱和100尾/箱)对平均体质量1g左右的日本医蛭Hirudo nipponia亲蛭交配率、减重率、产茧数量和体质量的影响,比较卵茧质量(0.05g、0.05~0.1g和0.1g)对孵出仔蛭数量的影响。结果表明:温度(24±1)℃、密度100尾/箱时亲蛭交配率(86±0.06)%和平均产茧量(0.87±0.14)枚/尾最高;亲蛭产茧后平均体质量下降(32.1±0.059)%;繁殖期间共收集卵茧870枚,孵化率87.47%;平均卵茧质量为(0.11±0.009)g(变化范围0.03g~0.25g);密度和温度对产茧量的影响极显著(P0.01),对卵茧平均质量和长短径的影响不显著(P0.05);(24±1)℃组亲蛭的产茧时间比(20±1)℃组缩短10~15d,单日卵茧最高收集量为43枚,(20±1)℃时单日最高收集量24枚;卵茧共孵出仔蛭5 648尾,随着卵茧质量增加产出的仔蛭数量和质量也增加。  相似文献   

10.
宽体金线蛭4个繁殖性状指标的相关性分析   总被引:1,自引:0,他引:1  
以随机选取的500条宽体金线蛭为样本,运用SPSS 13.0软件包中的双变量相关性分析(Bivari-ate)程序对宽体金线蛭种蛭体重、产卵茧量、卵茧重、出苗量等4个繁殖指标作统计分析。在对宽体金线蛭种蛭体重与产卵茧量、卵茧重、出苗量的两两相关性分析中得出:宽体金线蛭种蛭体重与产卵茧量、卵茧重、出苗量相关系数分别为0.8697、0.9351、0.6972,均呈极显著正相关;产卵茧量与卵茧重相关系数为-0.563,呈极显著负相关;卵茧重与出苗量、产卵茧量与出苗量之间的相关系数分别为0.8172、0.4873,均呈正相关。20~30 g种蛭平均产卵茧量、平均卵茧重、平均出苗量分别为2.78个、2.24 g、32.48条,为最适种蛭。  相似文献   

11.
The high prevalence (80–100%) of the marine leech Zeylanicobdella arugamensis (De Silva) on cage‐cultured Asian sea bass Lates calcarifer (Bloch) led us to investigate the percentage of juvenile leeches hatched from deposited cocoons, survival of juvenile and adult marine leeches at different salinity and temperature. The results showed that the hatching percentage of juvenile leeches was highest at salinity of 30 ppt (32.5 ± 2.8%) followed by 20 ppt (18.0 ± 4.3%) and 10 ppt (12.1 ± 1.4%), respectively. It was found that the adult and juvenile leeches could live up to an average range of 4–7 days at salinity ranging from 10 to 40 ppt. The juvenile leeches were able to hatch at temperature ranging from 25 to 35 °C but unable to hatch at 40 °C. The survival period of adult and juvenile leeches ranged from 11 to 16 days at 25 °C, which was comparatively longer than 5–13 days and 10 h – 5 days at 27–30 °C and 35–40 °C, respectively. The study provided the information on the physical parameters of salinity and temperature which are most optimal for the marine leech Z. arugamensis to propagate.  相似文献   

12.
ABSTRACT:   Larval false clown anemonefish of about 12 h after hatching were fed newly-hatched brine shrimp nauplii in natural (control) and copper-added seawater (40–640 µg–Cu/L) at 26.5 ± 0.5°C for 14 days. Survival rate of the fish increased with increasing copper concentrations up to 160 µg–Cu/L. The rates at 80 and 160 µg–Cu/L were 65 and 80%, respectively, and were significantly higher than that of the control (30%). A positive effect of copper addition on the survival rate was also observed in the other rearing experiment with the fish from seven different spawning chances. Growth rate of the survival fish was not affected by copper concentrations. The copper concentration of the survived fish increased with increasing copper concentrations in the rearing water.  相似文献   

13.
Experiments were carried out on the influence of quicklime, ammonia water, ‘Neguvon’ — Bayer and desiccation on the vitality of leeches. It was found that the efficacy of quicklime depends on its CaO content, on the dose of this compound, and, above all, on the pH of calcium hydroxide formed by mixing quicklime with water. The borderline value in this case is pH = 8.6. Quicklime containing 49% CaO did not affect the mature forms of leeches or their larvae in cocoons. The efficacy of other kinds of quicklime (53% CaO, 93% CaO and 99% CaO) also depended on the pH produced. Quicklime containing 99% CaO proved the most effective in destroying mature leeches and their cocoons; at the concentration of 250 ppm, it produces a pH higher than 8.6 (Table I).In acceptable doses, ammonia water affects neither mature leeches nor their larvae in cocoons.‘Neguvon’ — Bayer, though effective against mature leeches, does not affect the vitality of the larvae in cocoons in doses acceptable for practical use.Under laboratory conditions, drying up kills leech larvae in 24 h. This is therefore a radical means of combatting these parasites.  相似文献   

14.
Zeylanicobdella arugamensis (Annelida: Hirudinea), a marine parasitic leech, is currently affecting different species of cultured groupers, hybrid groupers, snappers and sea bass in Malaysia. Dillenia suffruticosa (Dilleniaceae), a medicinal plant found in Sabah, has been selected in our experiment to kill the leeches as a natural control method. The leech‐infested hybrid groupers were collected from aquaculture facilities, and the isolated leeches were challenged against methanol extract of D. suffruticosa leaves. The experiment was carried out using various concentrations of the extracts such as 25, 50 and 100 mg/ml. The methanol extract showed significant antiparasitic activity against Z. arugamensis with 100% mortality at a concentration of 100 mg/ml in 14.39 ± 3.75 min., followed by 50 and 25 mg/ml in 32.97 ± 9.29 and 41.77 ± 5.40 min., respectively. The phytochemical composition of the extract was determined using GC‐MS analysis to understand the nature of the principal compounds responsible for its antiparasitic properties. The leaves of D. suffruticosa demonstrated the presence of different bioactive compounds of various natures with varying percentages. Thus, it could be revealed that the methanol extract of D. suffruticosa mainly contains vital phytochemical compounds and showed an effective antiparasitic activity against the harmful leeches of hybrid groupers.  相似文献   

15.
Back Bay is an oligohaline, coastal bay in southeast Virginia, USA. Since 2004, leeches have been observed in the oral cavities of largemouth bass (Micropterus salmoides) in this body of water. Leeches (Myzobdella lugubris) have previously been documented in the oral cavities of largemouth bass in the Currituck Sound, which is confluent with Back Bay on its southern border. Supplemental stocking of largemouth bass in Back Bay since 2009 has resulted in an increasing population; however, concern exists that leech infestation may be negatively affecting health of larger fish, which are still less abundant than expected. Despite the wide distribution of this leech, there is little available literature regarding its health impacts on hosts. In this study, we examine potential impacts of oral leech infestations on stress markers and haematological parameters of largemouth bass in Back Bay. No significant changes in plasma glucose or cortisol were observed between leech‐infested and uninfested fish, and haematological parameters were not significantly different between the groups. Further, there was no evidence of systemic infections associated with leech infestation.  相似文献   

16.
The downstream movement of coho salmon fry and parr in the fall, as distinct from the spring migration of smolts, has been well documented across the range of the species. In many cases, these fish overwinter in freshwater, but they sometimes enter marine waters. It has long been assumed that these latter fish did not survive to return as adults and were ‘surplus’ to the stream's carrying capacity. From 2004 to 2010, we passive integrated transponder tagged 25,981 juvenile coho salmon in three streams in Washington State to determine their movement, survival and the contribution of various juvenile life histories to the adult escapement. We detected 86 returning adults, of which 32 originated from fall/winter migrants. Half of these fall/winter migrants spent ~1 year in the marine environment, while the other half spent ~2 years. In addition, the median return date for fall/winter migrants was 16 days later than spring migrants. Our results indicated that traditional methods of spring‐only smolt enumeration may underestimate juvenile survival and total smolt production, and also overestimate spring smolt‐to‐adult return (SAR). These are important considerations for coho salmon life cycle models that assume juvenile coho salmon have a fixed life history or use traditional parr‐to‐smolt and SAR rates.  相似文献   

17.
Spotted sand bass Paralabrax maculatofasciatus is a potential aquaculture species in Northwest Mexico. In the last few years it has been possible to close its life cycle and to develop larviculture technology at on pilot scale using live food, however survival values are low (11%) and improvements in growth and survival requires the study of the morpho-physiological development during the initial ontogeny. In this research digestive activity of several enzymes were evaluated in larvae, from hatching to 30 days after hatching (dah), and in live prey (rotifers and Artemia), by use of biochemical and electrophoretic techniques. This paper, is the first of two parts, and covers only the biochemical analysis. All digestive enzyme activities were detected from mouth opening; however the, maximum activities varied among different digestive enzymes. For alkaline protease and trypsin the maximum activities were detected from 12 to 18 dah. Acid protease activity was observed from day 12 onwards. The other digestive enzymes appear between days 4 and 18 after hatching, with marked fluctuations. These activities indicate the beginning of the juvenile stage and the maturation of the digestive system, in agreement with changes that occur during morpho-physiological development and food changes from rotifers to Artemia. All enzymatic activities were detected in rotifers and Artemia, and their contribution to enhancement the digestion capacity of the larvae appears to be low, but cannot be minimised. We concluded that the enzymatic equipment of P. maculatofasciatus larvae is similar to that of other marine fish species, that it becomes complete between days 12 and 18 after hatching, and that it is totally efficient up to 25 dah.  相似文献   

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