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家庭经营能不能走向现代化,如何走向现代化,一直是业内探索的重要课题。太谷县作为欠发达县份,30年来充分发挥家庭经营优势,优化统一经营,强化农业组织体系建设,积极发展资本、公司、科技三大农业,探索出在家庭经营基础上走向现代化的新模式。三大农业中,资本农业是基础、是核心,公司农业是关键、是枢纽,科技农业是保障、是支撑。三大农业是家庭经营基础上构建现代农业的三维组合。太谷实践表明,家庭经营虽然有一些局限,但能够吸纳各种有利要素,不断提高壮大,是一条值得探索的新路子。 相似文献
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大力推进果、草、畜、沼结合,不仅是果业持续稳定健康发展的迫切需要,也是推动全镇农业结构调整加快畜牧产业发展的迫切需要,因此,实现果、草、畜、沼结合经营模式,是实现以果为主,以草为纽带,果畜结合的生产模式。是提高果品产量,降低果品生产成本,提高果品的质量和价格,是农民脱贫致富的一条好路子。 相似文献
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以信息化促进现代渔业建设 总被引：1，自引：0，他引：1
信息化是当今世界发展的大趋势,是推动经济社会发展和变革的重要力量,与工业化、城镇化、市场化、国际化一起构成现代化建设的重要因素。渔业是大农业的重要组成部分,渔业信息化是农业信息化的组成部分。渔业信息化是渔业现代化的基础和重要标志之一。信息技术在渔业中的应用是优化渔业生产资源配置、推 相似文献
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<正>国家环境保护部部长周生贤指出:"低碳经济是以低耗能、低排放、低污染为基础的经济模式,是人类社会继原始文明、农业文明、工业文明之后的又一大进步。其实质是提高能源利用效率创建清洁能源结构,核心是技术创新、制度创新和发展观的转变。发展低碳经济,是一场涉及生产模式、价值观念和国家权益的全球性革命。"据报道,一些国家,例如新西兰畜 相似文献
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重在持续、重在提升、重在统筹、重在为民是河南省省委书记卢展工同志在省委经济工作会议上提出来的。四个重在是一个有机统一的整体,持续是根本,提升是手段,统筹是方法,为民是目的,四 相似文献
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<正> 山区渔业是整个大农业中的一条短线,距离人民生活需要相差很远。因此把发展山区渔业经济作为农村人民尽快发家致富的一项速效产业,前景广阔,大有可为。一、发展山区渔业是充分利用国土资源的一个重要方面。贫困的山区,地大物博,各类水资源丰富。只要有水源,比较贫瘠的土地、荒滩、荒水、洼地均可以被渔业所利用,变废为宝,造福人民。而且渔业的开发对水域是立体利用,既可养鱼、虾、鳖、蟹、鸡、鸭、猪、藕,还可以利用鱼池底泥作为农田最佳粪肥,实现良性循环。从生态学角度考虑.发展山区渔业不但是吃鱼的问题,而且是发展大农业的战略问题。一举多得,相得益彰。 相似文献
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休闲渔业是指将渔业资源、旅游资源和环境资源等进行优化配置,将旅游观光、休闲娱乐、餐饮、健身、科普等与渔业有机结合的一种新兴产业,亦称游乐渔业。休闲渔业是对渔业生产的一种补充,是对渔业资源的综合利用,是实现渔业产业结构调整的战略选择。发展休闲渔业,有利于拓宽渔业发展空间,是加快渔业结构调整、培育渔业经济增长点的迫切需要,同时发展休闲渔业,还加快由传统渔业向现代渔业转型,提高了渔业的比较效益。 相似文献
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在人们眼中大海是深邃的,因此渔业带给人更多的是一种神秘。说起渔业,我们知道的或许并不多。对于很多摄影师来说,渔业摄影是一个充满了美丽、淡定的艺术创作过程。浮光掠影、渔歌互答,小舟慢橹、山水一色……这些往往是渔业摄影作品中常见的、表现较多的创作主 相似文献
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长江、珠江、黑龙江三水系的鲢、镛、草鱼原种种群的生化遗传结构与变异 总被引：1，自引：0，他引：1
用LKB平板电泳仪聚丙烯酰胺凝胶电泳测定了长江、珠江及黑龙江的鲢、鳙及草鱼的原种8个种群16个酶位点的遗传变异。同种鱼不同水系种群之间存在着明显的生化遗传差异。长江、珠江、黑龙江鲢鱼种群的多态位点的比例分别是13.3％、26.7％、13.3％,平均杂合度分别是0.0493、0.0484、0.0511;长江、珠江鳙鱼种群的多态位点的比例都是31.3％,平均杂合度分别是0.1375,0.0977;长江、珠江、黑龙江草鱼种群的多态位点比例分别是30％,38％,23.1％,平均杂合度分别是0.1241,0.0961,0.0525。南方种群的多态位点比例有比北方的高的趋向。长江鲢—珠江鲢,长江鲢—黑龙江鲢,珠江鲢—黑龙江鲢的遗传相似度依次是0.9957,0.9955及0.9696;长江鳙—珠江鳙的遗传相似度是0.9955;长江草鱼—珠江草鱼,珠江草鱼—黑龙江草鱼,长江草鱼—黑龙江草鱼的遗传相似度依次是0.9679、0.9483及0.9324。长江种群与珠江种群这两个中央群体间的遗传差异较小,边缘群体黑龙江种群与中央群体长江、珠江种群间的遗传差异较大。黑龙江草鱼种群很小,其资源的保护工作应引起注意。 相似文献
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中国对虾循环系统的发生 总被引：1，自引：0，他引：1
采用组织学方法。研究了中国对虾循环系统的发生过程，在无节幼体第3期，起源于头胸甲皱褶部位的腹侧中胚层细胞通过增殖向背面迁移，在中肠的背面形成一中胚层板，此板两侧向背面上卷，合拢而成心脏，与此同时，该中胚层板两侧周围的中胚层细胞向两侧迁移，与体壁接触形成围心腔，心孔出现在无节幼体第5期，是由该处的心壁细胞直接内陷形成；心脏的形态结构随着幼体的发育而不断完善，至蚤状幼体第1期以后，组成心壁的细胞分化为单层的心肌细胞，随后其外包被一层由结缔组织细胞形成的心外膜，至仔虾期，心脏的外形和结构已与成虾的相似；背腹动脉发生的方式与时间和心脏的相同；中背动脉的发生包括两部分；心脏近端的中背动脉由心脏前端延伸而成，心脏远端的中背动脉则由幼体前端背部中胚层细胞形成，血细胞最早出现在无节幼体第1期。 相似文献
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CHRISTINA SOMMERVILLE 《Journal of fish diseases》1982,5(3):243-250
Abstract. Haplorchis pumilio (Looss, 1896) is a common digenean parasite of many species of fish of economic importance and has been found to infect cultured Sarotherodon spp. Fry of S. spilurus (Günther), S. mossambicus (Peters) and S. galilaea (L.) were experimentally infected with cercariae of H. pumilio from natural infections of Melanoides tuberculata (Müller) from an East African fish farm. Large numbers of cercariae were lethal to the fry within a few hours. Histopathological examination showed that the most significant pathological effect was focal haemorrhages in skeletal muscles in heavily infected fish. Migration of cercariae was through connective tissue and the final location of the metacercariae was connective tissue associated with skeletal structures. Clusters of cysts occurred at the bases of fins and in the loose connective tissue of the head, but the reaction to encysted metacercariae was insignificant. The overall effect on growth performance and thus economic importance of H. pumilio infection was assessed. Growth studies showed no significant differences between specific growth rate, food conversion ratios and condition of infected and uninfected fish. 相似文献
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The bacterial pathogen Flavobacterium psychrophilum was successfully identified from formalin-fixed, wax-embedded tissue blocks of infected rainbow trout heart and spleen tissues, using a polymerase chain reaction (PCR)-based assay. Filamentous bacteria were observed in haematoxylin and eosin and Giemsa-stained sections but no bacteria were recovered from the diseased fish using standard bacteriology isolation techniques. All infected fish had histopathological evidence of myocarditis or rainbow trout fry syndrome. Immunohistochemistry was attempted using three different anti-F. psychrophilum sera but the results were inconclusive, and an alternative molecular approach was therefore attempted. This paper describes the use of a PCR-based assay to help identify bacteria present in formalin-fixed, wax-embedded tissue samples. This is the first time that this technique has been used for the detection of fish bacteria from diagnostic samples. 相似文献
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通过人工投喂携带WSSV的毒饵，对性腺发育成熟的中国对虾（Fenneropenaeus chinensis）雄虾（♂）进行感染实验。采用nest-PCR（巢式PCR）技术，检测感染后的中国对虾雄性生殖系统受WSSV感染情况，同时选取感染严重的虾样进行电镜观察。巢式PCR检测结果表明，感染组中国对虾的精巢、输精管和精囊均被WSSV感染，其中精囊呈阳性的最多，输精管次之，精巢最少。通过电镜进一步观察发现，WSSV粒子只存在于精巢、输精管和精囊的结缔组织中，而在其他组织和生殖细胞中均未发现病毒粒子。其中，精巢中WSSV粒子存在于精巢内两个生精小管之间的结缔组织；输精管中WSSV粒子存在于管壁的结缔组织；精囊中WSSV粒子也只存在于精囊内膜的结缔组织和精荚膜的结缔组织中。PCR检测和电镜观察结果均表明，WSSV粒子能感染中国对虾的雄性生殖系统且对性腺感染存在着一定的组织特异性。 相似文献
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Jie Ma Timothy J. Bruce Luke P. Oliver Kenneth D. Cain 《Journal of fish diseases》2019,42(7):1065-1076
Co‐infection of rainbow trout with infections haematopoietic necrosis virus (IHNV) and Flavobacterium psychrophilum is known to occur, and it has been speculated that a combined infection can result in dramatic losses. Both pathogens can persist in fish in an asymptomatic carrier state, but the impact of co‐infection has not been well characterized or documented. In this study, it was hypothesized that fish co‐infected with F. psychrophilum and IHNV would exhibit greater mortality than fish infected with either pathogen alone. To test this, juvenile rainbow trout were co‐infected with low doses of either IHNV or F. psychrophilum, and at 2 days post‐initial challenge, they were given a low dose of the reciprocal pathogen. This combined infection caused high mortality (76.2%–100%), while mortality from a single pathogen infection with the same respective dose was low (5%–20%). The onset of mortality was earlier in the co‐infected group (3–4 days) when compared with fish infected with F. psychrophilum alone (6 days) or IHNV (5 days), confirming the synergistic interaction between both pathogens. Co‐infection led to a significant increase in the number of F. psychrophilum colony‐forming units and IHNV plaque‐forming units within tissues. This finding confirms that when present together in co‐infected fish, both pathogens are more efficiently recovered from tissues. Furthermore, pathogen genes were significantly increased in co‐infected groups, which parallel the findings of increased systemic pathogen load. Extensive tissue necrosis and abundant pathogen present intracellularly and extracellularly in haematopoietic tissue. This was pronounced in co‐infected fish and likely contributed to the exacerbated clinical signs and higher mortality. This study provides novel insight into host–pathogen interactions related to co‐infection by aquatic bacterial and viral pathogens and supports our hypothesis. Such findings confirm that mortality in fish exposed to both pathogens is greatly elevated compared to a single pathogen infection. 相似文献
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Abstract. Diagnosis and epidemiology of Mikrocytos roughleyi , the aetiological agent of Australian winter mortality of the rock oyster, Saccostrea commercialis (lredale & Roughley ), has been hampered by the small size of the pathogen and the low intensity of natural infections. Inoculation of experimental oysters with filtered, unpurified tissue homogenate from oysters infected naturally produced experimental infections after 22 weeks but hyperinfection was not successful. DNA was extracted from naturally infected, experimentally infected and uninfected oysters, then oligonucleotide primers were used in polymerase chain reactions to provide the basis for a molecular bioassay. One pair of primers produced an amplicon of 680 base pairs in length that was correlated directly to the presence of M. roughleyi in oyster tissues. The assay was able to detect a single organism of M. roughleyi in 400 host cells. 相似文献
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对虾暴发性流行病病原对中国对虾幼体及仔虾的人工感染研究 总被引：7，自引：1，他引：6
用对虾暴发性流行病病原（ＨＨＮＢＶ）作为人工感染实验的毒种来源,对中国对虾幼体及仔虾进行了人工感染研究,结果表明ＨＨＮＢＶ通过水体浸浴不能感染健康的中国对虾卵,幼体及仔虾;但可通过投喂感染健康的中国对虾仔虾,使其发病死亡,死亡的进程随着体长的增加而缩短。 相似文献
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白斑症病毒在日本对虾体内的感染增殖 总被引：9，自引：0，他引：9
用投喂患白斑症病毒病的虾组织人工感染日本对虾稚虾,每日取样,整虾冰冻切片,单克隆抗体的荧光抗体方法,原位观察病毒在虾体内的感染增殖,结果表明：感染后三天内,在感染虾的各组织器官内均未观察到明显的病毒感染的阳性细胞,每四天首先在鳃丝腔内的小量血细胞观察到病毒感染;第五天除血细胞外同时在血窦,鳃上皮组织,皮下组织内观察到,第六天进而在心脏,胃上皮组织内观察到：第七天进一步又在淋巴器官,中肠内观察到,八 相似文献
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由患不同程度褐斑病对虾的组织病理切片观察发现,各时期的褐斑病都包括甲壳及壳下内部组织两部分的病变;都有增生性和非增生性两种组织应答。故推论是由多种病原菌混合污染所致。在早期褐斑病虾之甲壳表面发现有粘液状分泌物,说明此时在对虾甲壳表面已有了局部免疫反应。 相似文献