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31.
对发生在山东境内的鲤竖鳞病进行了病原学研究,经过病原分离,人工感染实验和细菌学鉴定,确定豚鼠气单胞菌(Aeromonascauiae)是鲤竖鳞病的病原菌,在此基础上,得到了免疫原性较高和生产工艺简单的鲤竖鳞病疫苗,同时,对该疫功的安全性,免疫保护力和效价等进行了系统研究,并进行了一定范围的口服免疫应用试验。 相似文献
32.
Fish species identification is vital for aquaculture and fishery industries, stock management of water bodies and environmental monitoring of aquatics. Traditional fish species identification approaches are costly, time consuming, expert-based and unsuitable for large-scale applications. Hence, in this study, a deep learning neural network as a smart, real-time and non-destructive method was developed and applied to automate the identification of four economically important carp species namely common carp (Cyprinus carpio), grass carp (Ctenopharingodon idella), bighead carp (Hypophtalmichthys nobilis) and silver carp (Hypophthalmichthys molitrix). The obtained results proved that our approach, evaluated through 5-fold cross-validation, achieved the highest possible accuracy of 100 %. The achieved high level of classification accuracy was due to the ability of the suggested deep model to build a hierarchy of self-learned features, which was in accordance with the hierarchy of these fish’s identification keys. In conclusion, the proposed convolutional neural network (CNN)-based method has a single and generic trained architecture with promising performance for fish species identification. 相似文献
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34.
饲料中添加赖氨酸对鲤鱼生长的影响 总被引:6,自引:0,他引:6
高玉杰 《沈阳农业大学学报》2002,33(6):437-438
在鱼饲料中添加0.25%比例的赖氨酸的试验结果表明,可以提高鲤鱼的生长速度近20%。降低饲料成本可达13.7%,提高了鲤鱼产量。因此赖氨酸是鲤鱼生长发育的良好营养添加剂和生长剂。 相似文献
35.
利用淀粉凝胶电泳方法,对正常与患出血病的草鱼血清和肝脏、脾脏、肾脏、鳃、肠道和肌肉中乳酸脱氢酶(LDH)同功酶的活性作了比较,初步得出:正常与患病血清草鱼LDH同功酶相对活性具有显著性差异。病鱼与正常鱼的肝、肾、鳃LDH同功酶活性有显著性差异,各组份活性大小的次序也有改变,据此可作为草鱼出血病的一个病理标志。 相似文献
36.
[目的]研究氨氮对鲤幼鱼肝组织谷胱甘肽及其酶系的影响,阐析谷胱甘肽对环境胁迫的抗氧化防御机理.[方法]将黄河鲤在对照组(0 mg/L)和低(10 mg/L)、中(20 mg/L)、高(30 mg/L)3个氨氮处理组中染毒,研究氨氮胁迫6、24和48h后对肝组织中谷胱甘肽(GSH)含量、谷胱甘肽过氧化物酶(GSH-Px)和谷胱甘肽转移酶(GST)活性的影响.[结果]氨氮胁迫诱导黄河鲤幼鱼肝组织中GSH含量、GSH-Px和GST活性迅速升高,并在氨氮胁迫24h达到最大值,从而抵御氨氮造成的氧化胁迫.随着氨氮胁迫时间的延长,肝组织中GSH含量、GSH-Px和GST活性降低,抗氧化能力减弱.[结论]氨氮胁迫诱导黄河鲤幼鱼肝组织中谷胱甘肽含量及其酶系活性改变,以有效清除细胞中的活性氧和有毒代谢物,提高鱼类对环境的适应性. 相似文献
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以初始体重(33.90±0.11)g的福瑞鲤(FFRC Strain Common Carp,Cyprinus carpio)为研究对象,在基础日粮中分别添加0(对照组)、25、50和100 mg/kg低聚壳聚糖,于室内可控温循环水养殖系统中进行35 d的实验,研究了低聚壳聚糖对福瑞鲤生长、非特异性免疫及抗氧化指标的影响。结果表明,与对照组相比,低聚壳聚糖对福瑞鲤生长性能、肌肉成分无显著影响(P0.05);各实验组血浆碱性磷酸酶活力显著提高(P0.01);各实验组血浆总铁结合力水平、补体C3和C4含量有一定升高(P0.05);25 mg/kg实验组脾脏NO水平极显著提高(P0.01);50(P0.05)和100mg/kg(P0.01)实验组脾脏髓过氧化物酶活力均有显著提高;50mg/kg实验组血浆超氧化物歧化酶活力显著升高且丙二醛水平显著降低(P0.05)。研究表明,饲料中添加适量的低聚壳聚糖对福瑞鲤的非特异性免疫和抗氧化功能有明显的增强作用。实验条件下,低聚壳聚糖添加量为50 mg/kg较适宜。 相似文献
39.
Fish that have escaped from a cormorant’s (Phalacrocorax carbo sinensis (L.)) grasp and/or which could not be swallowed due to their size suffer from various injuries resulting in consecutive infections
and subsequent increased mortality. Computer-assisted image analysis was applied to describe the extent of such injuries.
Two-year-old mirror carp, Cyprinus carpio L. (TL 200–300 mm, W 200–300 g) showed injuries ranging over approximately 10% of the total body surface. Immediately after wounding, the damaged
epithelium (scars) cover 5–35%, and deeper subdermal wounds caused by the beak tip pervading into muscle tissue cover an area
of 1–2% of the total body surface. On the side impacted by the cormorant’s lower mandible, extensive areas of epidermal contusions
(scars) occur. As time progresses, these ratios change—deeper necroses represent up to 10% of the total body surface and healing
epithelial scars comprise just 1–2%. In wounded silver carp, Hypophthalmichthys molitrix Val. (300–400 mm, W 500–700 g), the share of subdermal wounds usually does not exceed 0.5% due to their compact scaly cover. During pond draining
due to fish harvesting, the size spectrum of wounded fish increases and may also often include bigger fish (e.g., European
catfish, Silurus glanis L.) up to 2.2 kg. 相似文献
40.
Panagiotis Varvarigos 《Aquaculture International》1994,2(3):197-205
The production economics of the emerging Bulgarian private carp and trout farming industry were assessed by surveying a representative sample of 20 private and state-controlled farms as well as visiting the National Fresh Water Fish Research Institute, the state-owned fish feed production plant and a fish processing plant.The major constraints for the development of profitable fish farming were found to be the lack of capital and the insecurity of tenure, which nonetheless, do not serve to discourage new entrants into the industry. The expected gross margin per tonne of carp produced in reservoirs or earth ponds is USD 487, while a tonne of trout farmed in concrete raceways shows a gross margin figure of USD 525. State-owned trout farms are only available for outright purchase at auctions, whereas carp farms may be rented, but only for a short term.Fish farmers could benefit from organizing themselves into producer groups in order to improve marketing and secure quality inputs. In particular, there is scope to source quality dry fish diets on both economic and environmental grounds.An extension advisory service is needed to support inexperienced new entrants and researchers should urgently evaluate what seem to be the most cost-effective methods of production. 相似文献