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美国家禽鸡蛋业和肉猪业垂直协作方式的比较分析 被引量:7
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作者 熊彩云 《世界农业》 北大核心 2004年第9期33-36,共4页
关键词 美国 家禽鸡蛋业 肉猪 垂直协作方式
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Effects of temperature and salinity on the development of embryos and larvae of the veined rapa whelk Rapana venosa(Valenciennes, 1846) 被引量:4
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作者 班绍君 张涛 +3 位作者 潘恒倩 潘洋 王平川 薛东秀 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第4期773-782,共10页
The major population of the veined rapa whelk Rapana venosa (Valenciennes, 1846), which is an important fishery resource, is facing a large decline in China. We studied the effects of incubation temperature (16-34... The major population of the veined rapa whelk Rapana venosa (Valenciennes, 1846), which is an important fishery resource, is facing a large decline in China. We studied the effects of incubation temperature (16-34℃ at salinity 30) and salinity (5-45 at 25℃) on the incubation period and subsequent larval development. In the temperature experiment, the shortest incubation period was 12 days at 34℃, the lower temperature limit was 16~C, the longest mean shell length (1 193+17 pan) occurred at 25℃ and the highest survival rate 72.28%+5.62% was observed at 28℃. In the salinity experiment, the shortest incubation period was 15 days at 25. The salinity tolerance range was 15-40, the longest mean shell length (855-4-9 μm) and the highest survival rate 72.93%~4.85% were both observed at 35. This study demonstrated that, during the egg-mass stage, temperature and salinity regimes influence later growth and survival of larvae. These observations deepen our understanding of the ecology and conservation of natural populations of Rapana venosa. 展开更多
关键词 Rapana venosa EMBRYO LARVAE TEMPERATURE SALINITY
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遵循经济规律 推动蛋鸡事业发展——北京华都集团蛋鸡经营方式的变革 被引量:1
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作者 赵黎明 《中国农村经济》 CSSCI 北大核心 2000年第4期39-43,共5页
关键词 中国 鸡蛋业 发展 北京 华都集团 蛋鸡 经营方式
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