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现行粮食定购定销制度非改不可
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作者 叶兴庆 《经济研究参考》 1997年第3期10-17,共8页
一、现行粮食定购定销制度的形成与含义 现行粮食定购定销制度是1994年以后重新确立起来的政府在粮食购销两个环节的管理体制。此前,粮食购销体制经历过从统到放的演变过程。从收购体制看,经历过从统购统销到合同定购与市场收购并存的... 一、现行粮食定购定销制度的形成与含义 现行粮食定购定销制度是1994年以后重新确立起来的政府在粮食购销两个环节的管理体制。此前,粮食购销体制经历过从统到放的演变过程。从收购体制看,经历过从统购统销到合同定购与市场收购并存的双轨制,再到1993年定购部分“保量放价”、全部实行市场收购的演变过程。从销售体制看,经历过从购销顺价的统销到购销倒挂的统销。 展开更多
关键词 粮食 定购价格 定量配给制 城镇居民 购销倒挂 平转 市场价 顺价
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Compensatory growth in hybrid tilapia (Oreochromis mossambicus×O. niloticus) reared in seawater, following restricted feeding 被引量:2
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作者 王岩 崔奕波 +1 位作者 杨云霞 蔡发盛 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2004年第4期414-420,共7页
Hybrid tilapia weighing 7.71 g were reared in seawater at 24.0-29.0℃ for 8 weeks. The controls were fed to satiation twice a day throughout the experiment, whereas treatment groups were fed at 0.5%, 1.5% or 3.0% body... Hybrid tilapia weighing 7.71 g were reared in seawater at 24.0-29.0℃ for 8 weeks. The controls were fed to satiation twice a day throughout the experiment, whereas treatment groups were fed at 0.5%, 1.5% or 3.0% body weight per day for 4 weeks, and then to satiation for the remainder of the experiment. During the first 4-week period, there was a curvilinear relationship between growth rate and ration size. Fish fed 0.5% and 1.5% rations displayed compensatory growth response of 2 weeks duration during realimentation. The weight-adjusted growth rate of fish fed at 3% ration was not significantly different from that of the controls by the end of the experiment, when none of the treatment groups had caught up in body weight with the controls. Hyperphagia was observed for the first 2 weeks of realimenatation in fish previously fed at 3% ration, but persisted for the whole realimentation period in groups previously fed at 0.5% and 1.5% rations. None of the feed restricted groups showed improved digestibility, feed efficiency, or protein and energy retention efficiency. 展开更多
关键词 hybrid tilapia compensatory growth feed restriction ration level
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