共查询到19条相似文献,搜索用时 78 毫秒
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采用固定后剥离卵膜后拍照的方法,在平均水温1.61℃下系统观察了黑龙江流域江鳕(Lota Iota Linnaeus)的胚胎发育。根据发育特征,将江鳕整个胚胎发育过程分六个大的发育阶段。黑龙江流域江鳕受精卵为淡黄色,近似圆球形,具有微粘性,比重略大于水,内部紧靠卵膜分布大量的脂肪滴,吸水膨胀后卵径为1.01±0.11mm,在平均水温为1.61℃水温条件下受精卵至破膜共历时1746h,需4106.98℃.h,进一步细分为21个发育时期。将黑龙江流域江鳕和新疆额尔齐斯河流域江鳕的胚胎发育过程进行了对比分析,为黑龙江流域江鳕的人工养殖和自然资源的复壮提供了基础资料。 相似文献
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本文以1981~1987连续七年野外调查采捕的1,800余尾江鳕群体标本的观测数据为依据,分别鉴定分析出——该水域江鳕的性状变异没达到亚种分化的程度,仍属“江鳕指名亚种”Lota Lota Lota(Linné)。种群的年龄组成是0~+~6~+龄。耳石半径与体长的关系式为:L=0.9542+166.8599R。体长与体重关系式为:W=3.6262~(-0.3)L~(3.2175)。3~+~4龄性腺成熟产卵。个体怀卵量与体长和体重的相关公式分别为:(?)=15.5778L~(2·7299)和(?)=4145.536+596.7289W。0~+~1~+龄幼鱼以石蝇稚虫为主的水生昆虫和底栖动物为食,2龄为食性转变时期,2~+龄以上主食別种小型鱼类。生殖洄游上溯摄食不停,仅产卵时短暂停食,产毕即开食,降河回湖后为其摄食言肥旺季。 相似文献
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最近,河北省水产局组织有关专家对江鳕全人工养殖技术研究与应用技术进行了阶段性现场验收。江鳕是鳕科鱼类中唯一的淡水种类,也是我国冷水鱼类的珍稀物种,主要分布于额尔齐斯河流域和乌江上游,目前是全世界抢救性开发的品种之一。它肉质细嫩, 相似文献
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研究可可托海水库江鳕(Lota lota)个体生物学,丰富其基础生物学资料,可为其种质资源保护与合理利用提供科学依据。2012-2014年,从可可托海水库及入库河道采集江鳕样本共196尾,测量其生物学常规数据,以耳石为主要年龄鉴定材料,对其形态特征、生长和繁殖特性及食性进行分析。结果表明,江鳕体长与体重相关方程为W=0.011L2.926;von Bertalanffy的体长、体重生长相关方程分别为L_t=101.8[1-e~(-0.132(t+0.594))]、W_t=8 982[1-e~(-0.132(t+0.594))]~(2.926),体长、体重生长速度和体重加速度方程分别为dL/dt=13.438e~(-0.132(t+0.594))、dW/dt=3 556.872[1-e~(-0.132(t+0.594))]~2×e~(-0.132(t+0.594))和d~2W/dt~2=469.507e~(-0.132(t+0.594))×[1-e~(-0.132(t+0.594))]~2×[3~(e~(-0.132(t+0.594)-1))];肥满度为0.52~1.34,季节、性别和鱼体大小间肥满度数值基本一致;雌雄比1.4∶1,雌雄个体最小性成熟年龄均为2+龄,性腺Ⅳ期的雌、雄繁殖个体平均成熟系分别为(3.59±0.93)%和(7.93±2.50)%,绝对怀卵量为(274 445.06±98 039.81)粒,相对怀卵量为(417.49±112.30)粒/g。江鳕为肉食性鱼类,小型鱼类在食物中的重量比和出现率分别为94.73%和89.38%,全年平均摄食率和饱满度分别为(86.06±12.51)%和(3.72±3.44)%。人类活动对库区江鳕资源造成负面影响,防止过度捕捞、护幼捕大措施,可使其资源得到保护与合理利用。 相似文献
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Abstract Population viability analysis (PVA) is a frequently used conservation tool for the assessment of long‐term survival of populations. Based on demographic information from published literature, a PVA model using VORTEX was constructed for the burbot Lota lota (L.), a freshwater fish species believed extinct in the United Kingdom since the 1970s. The model was constructed to evaluate the persistence of a single burbot population over a 100‐year period as part of an assessment of the feasibility of reintroducing the species to rivers of its former distribution in England. Population persistence was highly variable and dependent on juvenile survival and spawning regularity. Under high juvenile survival scenarios, all populations persisted and were maintained at the carrying capacity. At low juvenile survival, population persistence was highly influenced by spawning regularity. Sensitivity analysis indicated that females must successfully spawn approximately every second year to guarantee 95% population survival. The analysis suggests that the long‐term viability of any potential reintroduced burbot population will be dependent on the environmental conditions related to spawning success. 相似文献
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采用酸水解法测定野生江鳕(Lota lota)的肌肉氨基酸含量,分析其氨基酸的种类与比例,并对其营养成分进行评价。结果表明:江鳕肌肉中含有17种氨基酸,总含量为(72.43±1.16)%(干样),其中7种为人体必需氨基酸(EAA),总量为(29.82±0.57)%,占氨基酸总量的41.17%,其中必需氨基酸的组成比例与联合国粮农组织/世界卫生组织(FAO/WHO)的标准相符。江鳕的第一限制性氨基酸为蛋氨酸+胱氨酸,4种鲜味氨基酸(DAA)总量为(28.34±0.35)%(干样)。必需氨基酸指数(EAAI)为62.58。研究表明:江鳕含有丰富的氨基酸具有很高的营养价值和保健作用。 相似文献
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Krzysztof Kupren Izabela Trąbska Daniel Żarski Sławomir Krejszeff Katarzyna Palińska-Żarska Dariusz Kucharczyk 《Aquaculture International》2014,22(1):29-39
This study analyzed the morphological development and allometric growth patterns of Lota lota L. (burbot) larvae reared under controlled laboratory conditions. From hatching to day 50, twenty larvae were sampled each [between 1 and 14 days post-hatch (DPH)] or every second day (between 14 and 50 DPH) and measured under a stereoscopic microscope using analytic software. Based on the external morphology, the different stages during early development of burbot were identified: yolk sac larva 0–8 DPH [3.92–4.37 mm total length (TL)]; preflexion larva 9–26 DPH (4.57–12.06 mm TL); flexion larva (between notochord degradation and its replacement with rays) 28–34 DPH (14.00–16.34 mm TL) and postflexion larva/juvenile 36–50 DPH (18.20–29.27 mm TL). Allometric growth patterns of some parameters (e.g., total length, head length, body length, tail length, head depth, body depth, eye diameter) were modeled by a power function and described by the growth coefficient. Organogenesis and changes of body proportions in burbot larvae were more rapid and complex during the yolk sac and preflexion phase of development as larvae developed most of their sensorial, feeding, respiratory and swimming systems and after notochord flexion, when most morphological changes were related to the progressive transformation from pelagic larva to demersal larva/juvenile. 相似文献