北方地区的海水育苗场多建于上世纪80～90年代初。用来培育东方对虾和中华绒螯蟹种苗。当时解决种苗开口饵料的方法是直接向育苗水体中施肥,使天然单胞藻达到一定数量,再搭配一些蛋黄等代用饵料,足以使幼体顺利渡过开口关。所以多数育苗场没有兴建培育单胞藻的相关设施。时过境 Sea nurseries in northern China were mostly built in the early 1980s and early 1990s. Used to cultivate Oriental shrimp and Chinese mitten crab seedlings. At that time, the solution to solve the seed and seed feed opening was to apply fertilizer directly to the nursery water to make the natural monocyst reach a certain amount, and then use some alternative feed such as egg yolk to make the larvae pass the opening and closing smoothly. Therefore, most nurseries do not have the facilities to cultivate monocytogenes. Transit