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北京市密云县境内的遥桥峪水库建成于1984年,总面积约1.1平方公里,注入水库的河流有南峪沟、大沟,其下游为安达木河。该水库的设计水位为468.1米,最高水位为466米,死水位为428水,总库容1940万立方米,水库大坝长262.1米,坝高54.2米.现库区水域内主要 相似文献
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香鱼 (Plecoglossusaltivelies )属鲑形目香鱼科 ,肉质细腻 ,体色美 ,味清香。香鱼在日本的养殖、放流及游钓业十分发达 ,在我国其养殖前景亦十分乐观。在香鱼的育苗及养殖过程中 ,经常见到一些 (1% -2 % )鱼体出现异常的体型 ,如”V”型或倒”V”型 ,尾部上翘的现象。本文通过采集体型异常的养殖香鱼 ,描述其形态学特征 ,并探讨了致畸原因。1 材料和方法香鱼标本主要采自温州乐清的几个养殖基地 ,共 2 9尾 ,其中 2尾是正常鱼。 (见表 1)表 1 香鱼标本的基本特征来源养殖状况数量体长 (cm)体重 (g)平均范围方… 相似文献
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香鱼又称海胎鱼、油香鱼、细鳞鱼、瓜鱼、平鱼、八月香、肥鱼等,在日本称鲇,是一种一年生小型珍稀经济鱼类。主要分布在日本的北海道南部至鹿儿岛.朝鲜沿海及我国的渤海、黄海、东海及台湾的某些入海溪河中。 相似文献
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1997年,三门峡市开展革胡子鲇池塘养殖试验21亩,平均亩产2271公斤,亩纯收入0.73万元,投入产出比为1:1.47。 相似文献
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怀头鲇的生物学与养殖 总被引:3,自引:0,他引:3
怀头鲇 (Silurus soldatovi)曾用名黑龙江六须鲇和东北大口鲇,俗称怀头和怀子,隶属鲇形目、鲇科、鲇属,主要分布于黑龙江和辽河水系,是一种大型肉食性经济鱼类。 一、怀头鲇的生物学 1.形态特征 怀头鲇头部宽扁,胸腹部短胖,尾部长且侧扁;眼小、口小,牙齿细密且锐利;上颌 (长 )须 1对,下颌 (短 )须 2对;背鳍短小无硬棘,胸鳍有 1枚硬棘 (内侧光滑无锯齿状缺刻 ),臀鳍特长并与尾鳍相连,尾鳍不明显分叉,上叶稍长于下叶。体表无鳞,富有粘液。胃大,肠短。在较清澈的水体中,腹部为白色或淡黄色;背部和两侧呈金黄… 相似文献
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比较了黄河中上游水域中特有鱼类兰州鲇(Silurus lanzhouensis)与鲇(Silurus asotus)主要形态学特征和血清生化指标,以期对兰州鲇的资源保护和人工养殖提供参考.结果显示,兰州鲇的颌须长/全长显著大于鲇(P<0.05);眼径/全长以及口裂宽/全长两者无显著差异(P>0.05),但兰州鲇眼径显著低于鲇(P<0.05);兰州鲇血清谷丙转氨酶(ALT)显著高于鲇(P<0.05),血清钙(Ca)、磷(P)和白球比(A/G)显著低于鲇(P<0.05),血清谷草转氨酶(AST)、总蛋白(TP)、白蛋白(ALB)、球蛋白(GLO)、白球比(A/G)、尿素(BUN)、总胆固醇(Chol)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-c)、低密度脂蛋白胆固醇(LDL-c)两者均无显著差异(P>0.05).研究表明,兰州鲇眼径较小,第一颌须较长,2种鲇在形态和血清生化指标上存在一定差别,在钙磷矿物营养代谢上有较大差异,而在蛋白与脂代谢强度上有相似性. 相似文献
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在水温14.8-21.2℃,比重1.008-1.013条件下,采用轮虫、微颗粒饲料、卤虫无节幼体及桡足类,以不同配比组成3组不同的饵料系列投喂香鱼仔、稚鱼。结果表明:采用轮虫 配合饲料-桡足类 配合饲料的系列饵料,在仔稚幼鱼生长速度和成活率等方面优于单纯使用生物饵料组成的饵料系列,并且可以降低育苗成本。 相似文献
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A feeding trial was conducted to evaluate the optimum requirement of dietary available phosphorus (AP) for juvenile walking catfish, Clarias leather. Six practical diets were formulated to contain graded levels (2.2, 3.9, 5.5, 7.1, 8.8 and 10.4 g kg?1) of AP from dietary ingredients and monocalcium phosphate. Each diet was randomly fed to triplicate groups of fish with initial mean weight of 7.94 ± 0.08 g in floating cages (1.5 × 1.5 × 2.0 m) suspended in an earthen pond, and each cage was stocked initially with 60 fish. Fish were fed thrice daily (07:30, 13:00 and 17:30) to apparent satiation for 10 weeks. Both specific growth rate (SGR) and protein efficiency ratio significantly increased with increasing AP from 2.2 to 5.5 g kg?1 (P < 0.05) and then levelled off. Dietary AP levels significantly influenced whole‐body protein, lipid and ash contents as well as condition factor and hepatosomatic index (P < 0.05). Whole‐body and vertebrae phosphorus contents showed similar patterns as SGR in response to dietary AP content. Broken‐line analyses based on SGR, phosphorus contents in the vertebrae and whole‐body indicated the AP requirements were 5.8, 7.2 and 7.5 g kg?1, respectively. 相似文献
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Abstract. Chinese catfish, Clarias fuscus (Lacepède), within three size ranges were evaluated for growth, survival and feed conversion ratios (FCR). A 4 × 3 factorial design was used during year-long trials which included four temperatures (20,25,30 and 35 °C) and three feeding rates with commercially formulated salmon/trout feed. Specific growth rates of juvenile fish (1–60g) were highest, ranging from 1–64% body weight/day at 20°C (2%/day feed rate), to 4–94%/day at 25°C (6%/day feed rate). Specific growth rates of sub-adult fish (60–150g) averaged 0–65%/day, with no significant difference between temperature-feed rate treatments. Specific growth rates of adult fish (>150g) were lowest, averaging 0–30%/day for grouped feed rate treatments at 25°C, and 0–16%/day at 30°C. Most mortalities occurred during the juvenile stage, with survival ranging from 0% at 35°C(2% feed rate) to 96% at 30°C(6% feed rate). Survival was 95–100% with sub-adults and adults. FCR were 1 to 4 with juveniles, 2 to 12 with sub-adults, and 3 to 22 with adults. These trials suggest that optimal growth and FCRs were obtained at 25°C; with feed rates of 6%/day with juveniles, 2%/day with sub-adults, and 1%/day with adult fish. Final yields at 25 and 30°C indicate that even though growth and FCR are optimal at 25°C, survival was greater at 30°C, which compensated for reduced growth performance at this temperature. Yields at 25 and 30°C were almost double those at 20°C. 相似文献