Procambarus clarkii and Cherax quadricarinatus is a large freshwater crayfish native to the southern United States and northern Mexico [1,2] . Procambarus clarkii is called crayfish in China. it has strong viability and has been spread to other parts of the world for natural reproduction, forming local populations. it has become a world-wide edible shrimp. Since it was introduced into China in the 1930s, it has been widely distributed in rivers, lakes, ditches, ponds and rice fields in our country, especially in the middle and lower reaches of the Yangtze river [3] . Crayfish is very popular in the market because of its rich nutrition, chewy meat and delicious taste. At present, it has become an excellent new breed of freshwater aquaculture in China's southern and northern regions. The cultivation area and output of crayfish in our country continue to grow rapidly. From 2007 to 2016, the national crayfish cultivation output increased from 265,500 tons to 989,100 tons, reaching an economic output value of 146.610 billion, with nearly 5 million employees in the entire industry chain. it is one of the most popular cultivation varieties in recent years [4] .
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2015
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2013
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2012
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2009
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2004
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2003
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