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近年来,全球水产养殖业得到迅速发展,其中我国的发展占有重要位置。据FAO资料,当前全球海、淡水水产养殖总产量高达4500多万吨,其中中国水产养殖产量为3200万吨左右,占全球水产养殖总产量的71%以上(FAO 2002)。我国水产养殖的养殖总产量占我国渔业总产量的60%以上。已成为世界上唯一一个养殖产量超过捕捞产量的国家。 相似文献
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环境营养学研究与水产养殖业的可持续发展 总被引:2,自引:0,他引:2
1 我国水产养殖业的发展现状
随着国民经济的高速发展和农业结构调整的不断深入,我国水产养殖业得到了持续、迅猛的发展。从1988年起,我国水产养殖的产量首次超过捕捞产量,是世界上唯一一个养殖产量超过捕捞产量的国家,且养殖产量已占到世界养殖总产量的70%以上。最新统计数据显示,2005年我国的水产品总产量为5107.6万吨,同比增长4.2%,其中养殖产量为3395万吨,占总产量的66.48%。水产养殖业的发展,一方面使水产品的供求关系发生了很大的变化;另一方面改善了产业结构,推动了整个渔业经济的发展。 相似文献
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一、无公害水产动物养殖利国利民
水产养殖业是我国渔业的重要组成部分,水产品是农产品中的重要门类之一。人类的肉食来源于动物,水产品是提供给人类丰富的蛋白质食物。近些年来.随着人们生活水平的提高的需要以及出口的发展,我们国家制定了一系列鼓励发展水产养殖政策,加大科技投入.通过广大科技人员及饲养者(和渔民)共同努力.使水产品生产得到了迅速发展。 相似文献
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当前水产养殖效益影响因素及发展对策研究 总被引:2,自引:0,他引:2
我国是世界上唯一一个水产品养殖产量超过捕捞产量的国家,且养殖产量已占到世界养殖总产量的70%以上。统计数据显示,2005年我国的水产品总产量为5107.6万吨,其中养殖产量为3395万吨,占总产量的66.48%,养殖产量占有如此高的比重,这在世界主要渔业大国中是绝无仅有的。2008年1~5月全国水产品总产量为1557.2万吨,同比增长4.46%。水产养殖业的发展,一方面使水产品的供求关系发生了很大的变化;另一方面改善了产业结构,推动了整个渔业经济的发展。 相似文献
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一、我省水产饲料发展形势1.水产养殖业发展形势我省是全国水产养殖业和水产品消费最大的省份,水产养殖业在我省的农业中占有十分重要的地位。90年代以来,我省水产养殖业产量平均每年递增13%,是我省农村经济中发展最快的产业之一。1997年,我省的淡水养殖总产量超过了180万吨,预计今后几年内,养殖产量仍以每年10~15万吨的幅度递增。在养殖品种方面,随着经济的不断发展和人们消费水平的提高,低质的滤食性鱼类(如绍、编鱼的产量在总产量中所占比重将逐步减少,而优质的吞食性鱼类(如草鱼、罗非鱼)的产量会越来越大,同时,加州护… 相似文献
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正改革开放以来,水产养殖业同其他行业一样有着丰硕的成果,特别是1985年我国确立了"以养为主"的渔业发展方针,水产养殖业成绩斐然,我国是世界上唯一的水产养殖产量超过捕捞产量的国家,养殖产量占世界养殖总产量的70%。特别是静水土池塘养殖,我国的水平遥遥领先。2016年全国水产品产量6 900多万 t,其中养殖5 100多万 t。淡水养殖产量3 179万 t,占淡水产品产量的93%,鱼类产量2 815万t,淡水 相似文献
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2003年,广东渔业以结构调整和渔民增收为中心任务,大力发展水产养殖业,深化加工,着力提高水产品质量,在“非典”疫情突发、部分水产品出口受阻等不利情况下,水产养殖仍继续保持了持续增长的势头,全年水产品总产量635万吨,比上年增长1.1%,其中水产养殖产量440万吨,占水产 相似文献
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福建地处我国的东南沿海,海岸线长而曲折,浅海滩涂面积大,适养区域广阔,海水、淡水养殖业发达。主要养殖品种有鳗鲡、大黄鱼、真鲷、牡蛎、虾、鲍、大弹涂鱼等,水产品产量位居全国第三。由于水产养殖规划不合理,养殖和病害防控技术落后,致使养殖环境污染,病害频繁,水产品质量控制面临重大风险。近年来,主要进口国(日本、美国、欧盟、韩国)借助技术和贸易壁垒加强了对我国出口水产品中有害物质残留的检测,标准相当苛刻,检测面广,出口贸易的技术风险已经成为制约水产养殖业健康发展的重要因素。水产养殖业经过几年的治理整顿,先后化解了氯霉素… 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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以国际标准强毒R株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离MG,并收集感染鸡所产蛋分离MG。结果表明,人工感染48小时后上、下呼吸道及肺已被全面感染,96小时气囊已被感染,120小时输卵管已能分离到MG,卵巢始终分离不到MG。人工感染鸡自144小时便能在其所产蛋中分离出MG。药物治疗能在72小时内消除感染,油乳剂苗则需24天后逐渐降低蛋内MG分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内MG,但以研制的种蛋浸泡剂药浴效果为最好。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献