北方地区受气候条件和资源条件的限制,南美白对虾养殖一般采取单茬养殖模式。随着养殖规模的不断扩大,受苗种质量和水域条件的影响,发病率呈上升趋势,并以7月份为发病高峰期,使养殖成本逐年上升,至9月底10月初集中出售,销售价格逐年下降,以至养殖效益逐年下滑。为此,我们于2004 The northern region by the climatic conditions and resource constraints, the South American white shrimp farming generally take single cropping mode. With the continuous expansion of breeding scale, affected by the quality of seed and water conditions, the incidence is on the rise, and the peak incidence in July so that farming costs increased year by year to focus on the sale of end of September early September, the sales price year after year Decline, as far as farming benefits decline year by year. To this end, we in 2004