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魏永信 《国外畜牧学(猪与禽)》1998,(3)
每一家商业规模的猪场都需要一间医院,因为猪场内总是有一些猪得病或受伤从而需要养在隔离圈舍内待其痊愈或是最终将其淘汰。但是,正如每一个猪场管理者都见到的那样,提供需要加以特别护理的圈舍是比较容易的。比较困难的是要有时间和人员参与护理工作。欧洲的一位兽医... 相似文献
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不同地区或不同厂家(饲料厂和养殖场)有不同的条件(不同的饲料、环境、品种和生产水平等),在某一特定条件下研究出的最佳饲料配方不可能在所有条件下得到最佳效果。因此,各地或厂家应根据本地或本厂的具体条件和要求,研究和配制最佳饲料配方。 相似文献
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家住沧州盐山县城的门胜霞下岗后回农村老家养羊致富,成了盐山的新鲜事。 今年47岁的门胜霞,1993年在县某公司下岗时,不禁心中迷惘,常常把自己闷在屋里。在丈夫开导、鼓励下,1998年,她只身回老家创办了小尾寒羊养殖场。 万事开头难。面对人们的不理解,她磨破了嘴皮,到处讲小尾寒羊的优点,养殖的好处。功夫不负有心人。她的诚心感动了与她接触的每一个人,最后在镇党委和妇联的支持下,一个占地3.7亩建有11间单舍的养殖场终于建成。当年她从山东梁山引进小尾寒羊200只,使养殖初具规模。为了掌握饲养管理技术,她… 相似文献
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麝类动物(Moschus spp.)雄性个体可分泌麝香,是濒危珍稀资源动物,驯养是濒危麝类动物的迁地保护(ex situ protection)和麝香生产的重要方式。我国从1958年开始麝类驯养,初期的主要驯养麝种为林麝(M.berezovskii),从1990年开始马麝(M.sifanicus)驯养。论文总结了濒危马麝的分群驯养,归纳了麝场选址、麝场修建、圈舍设计、分圈分群及日常驯养管理等方法体系,对我国麝类驯养、资源保育及麝香生产等提供重要参考。 相似文献
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1养殖的现状1.1鳗鲡养殖比重最大淡水名优鱼类养殖业就产值而言,目前仍以鳗鲡养殖比重最大。据统计,2000年我国在出口的水产品中,烤鳗仍居水产品出口创汇第一位。由此可见,鳗鲡在我国水产品中占有相当重要的地位。我国的养鳗业经过1996年的市场价格暴跌风波后,采取了相应的策略,控制了养殖的规模,提高了产品的质量,降低了养殖和加工成本,使产品竞争力得到了增强。但我们应该清醒地认识到这个行业仍是高投入、高风险的行业,必须对养殖规模进行有效控制。1.2市场价格趋于疲软在我国淡水养殖的鱼类品种中,由于养殖面… 相似文献
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Although fish invasions have implications for conservation and resource management, research on public attitudes toward nonnative fishes is lacking. We surveyed boat and canal bank recreational anglers in the Everglades to assess their awareness, preferences, and perspectives of native versus nonnative fishes. Our findings showed that 79% of anglers were aware of the presence of nonnative fishes, and overall awareness was positively affected by the frequency of fishing, and years of angler experience at study sites. Frequency of fishing had a stronger effect on canal bank anglers. Boat anglers had higher awareness of nonnatives, higher familiarity with “nonnative” terminology, and expressed greater preferences for native fish. Most anglers favored native species (72% preference), and targeted native fishes, particularly Florida Largemouth Bass (66%). Overall, findings show that despite the prevalence of nonnative species, anglers favored native fishes and supported native fish conservation. 相似文献
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《Journal of aquatic animal health》2013,25(1):69-77
Abstract Data are presented from studies on heritable melanoma formation in certain hybrids of Xiphophorus fishes. In the best investigated case, benign and malignant melanomas were caused primarily by hemizygous and homozygous loss, respectively, of a tumor suppressor gene that promoted final pigment cell differentiation, although additional genetic events may be of importance. In other melanoma cases, different genes, most of them presumably also tumor suppressor genes, have been implicated in the development of melanomas and may interact at other levels of pigment cell development, such as commitment, migration, or homing of pigment cell precursors. Importantly, genetic factors have been identified that do not allow melanoma formation despite the loss of tumor suppressor genes. Taken together, these findings stress the complexity of tumorigenesis and the heterogeneity of pathways that lead to cancers of the same histological type. 相似文献
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中国淡水鱼类种质资源的保护和利用 总被引:3,自引:0,他引:3
本文简要介绍了目前世界鱼类资源概况、我国鱼类资源现状,以及鱼类生物多样性的极丰富程度与易被破坏性,还介绍了造成鱼类种类减少或区系组成变化的主要原因以及造成鱼类遗传多样性减少的内在原因和外部原因;比较详细的提出了鱼类种质资源保护的目的、策略及措施。并就我国鲤科鱼类繁育群体的大小、鱼类种质的鉴定与评价及利用前景作了分析。 相似文献