| 摘要: |
| 通过稻田原位围隔（每个20 m2）试验，比较了不同规格的克氏原螯虾生长、存活及养殖效果。试验设计了三个不同放养规格处理组，小规格平均体重为3.35 g，中规格为6.49 g，大规格为10.35 g，每个处理组有3个重复，试验开始时投放的虾种生物量均为1 000 g。试验结果为：小规格组围隔内伊乐藻生物量和覆盖度急剧减少，可能与放养密度过高有关；虾体重特定生长率与放养规格呈现负相关的趋势；大规格组的存活率（77.3%）最高，显著高于中规格组（58.1%）和小规格组（60.1%）；大规格组试验前后的性比出现了显著的变化，但中规格组和小规格组试验前后的性比均无明显变化；经过45 d养殖，大规格组平均体重为45.15 g、单个围隔平均产量为3.64 kg；中规格组平均体重37.64 g、围隔平均产量3.32 kg；小规格组平均体重27.47 g、围隔平均产量5.08 kg；大规格组饲料系数为1.85，中规格组1.77，小规格组2.34；大规格组单个围隔毛利润为165元，中规格组79元，小规格组96元。这些结果表明放养大规格（10 g左右）虾种时，养殖死亡率低、产品档次高，因而能以较低的产量获得最好的经济效益。 |
| 关键词: 克氏原螯虾 放养规格 特定生长率 存活率 养殖效益 稻田 |
| DOI：10.14188/j.ajsh.2020.04.008 |
| 分类号:S932.5+1 |
| 基金项目:湖北省技术创新专项重大项目（2018ABA102）；国家重点研发计划“蓝色粮仓科技创新”重点专项项目（2019YFD0900304） |
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| Growth performance and culture effects of red swamp crayfish with different stocking sizes in paddy field |
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HUANG Feng1,2, FENG Yuming2, LI Hao2, LI Wei2, ZHANG Tanglin2
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1.College of Fisheries and Life Science， Dalian Ocean University, Dalian 116023, Liaoning, China;2.Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, Hubei, China;3.University of Chinese Academy of Sciences, Beijing 100049, China
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| Abstract: |
| The growth, survival and culture effects of red swamp crayfish (Procambarus clarkii) with different stocking sizes were compared by in situ net-enclosure experiment in the paddy field. We designed three treatment groups of small-, medium- and large-sized crayfish seed of which body weight was averaged to be 3.35g, 6.49g and 10.35g, respectively. Each treatment had three replicates, and the stocking biomass of crayfish seed was 1 000 g for each treatment at the beginning of the experiment. The main results were as follows: the sharp decrease in waterweed biomass and coverage for the small-sized treatment might be mainly related to high stocking density; specific growth rate in body weight of the crayfish was negatively correlated with stocking size; the survival rate (77.3%) of large-sized treatment was the highest, which was significantly higher than those (58.1%, 60.1%) of medium- and small-sized treatments; there was a significant change in the sex ratio (females to males) of large-sized treatment before and after the experiment, but there was no significant change in the sex ratio of medium- and small-sized treatments. After 45 days of cultivation, the average yield of the crayfish per net-enclosure (20 m2) in the large-, medium- and small-sized treatments was 3.64 kg, 3.32 kg and 5.08 kg, respectively, and their individual weight averaged to be 45.15 g, 37.64 g, and 27.47 g, respectively. The feed conversion ratio was 1.85 for the large-sized treatment, 1.77 for the medium-sized treatment, and 2.34 for the small-sized treatment. The average gross profit per net-enclosure in the large-, medium- and small-sized treatments was 165, 79 and 96 yuan, respectively. The above results indicated that there were low mortality rate and high product grade of the crayfish, thereby, the best economic benefit could be obtained with lower yield when stocking the large-sized crayfish seed (about 10 g in body weight). |
| Key words: Procambarus clarkii stocking size specific growth rate survival rate culture benefit paddy field |
