青虾已成为我国重要的淡水养殖对象，是优化养殖结构的主要品种，近几年来出现了快速发展的新势头。但由于当年放养的虾苗秋季都要繁殖，因而在青虾养殖中存在大小虾同池、小规格虾比例过大的矛盾，小规格虾占总产量的４０％－５０％，严重影响了青虾养殖的规格和经济效益，成 Freshwater shrimp has become an important freshwater aquaculture object in China and is the main species for optimizing aquaculture structure. In recent years, there has been a new trend of rapid development. However, due to the stocking of shrimp in the fall should be breeding in the breeding, there are shrimp in the pond shrimp with the same pool, the proportion of small size shrimp too much conflict, small size shrimp account for 40% -50% of the total output, seriously affected the green Shrimp farming specifications and economic benefits into