近10多年来,由于农业的精耕细作,广泛积肥以及工业污水的影响,天然饲料资源日趋减少,从而影响了草鱼养殖产量的提高。过去,江苏、浙江一带以养草鱼为主,现在也逐渐改养鲢鱼、鳙鱼、罗非鱼等,草鱼的产量由原来的40％下降到20％左右。占广东省养殖面积一半的顺德、南海、中山三 In the past 10 years, the natural feed resources have been reduced due to intensive farming of agriculture, extensive fertilizer production and industrial sewage, which has affected the increase of grass carp aquaculture production. In the past, Jiangsu and Zhejiang provinces mainly reared grass carp, and now they gradually recuperate silver carp, bighead carp and tilapia. The output of grass carp has dropped from 40% to about 20%. Shunde, Nanhai and Zhongshan III, which account for half of the farming area in Guangdong Province