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虾病的流行,已成为养虾业稳定发展的制约因素之一。 1 虾病流行情况本省人工养殖对虾发病始见于1985年。当时在黄骅、海兴等地的人工育苗过程中,发生了聚缩虫病和气泡病,严重地影响了幼体的变态发育,甚至导致大批死亡。随后,每年均发现不同程度的各类虾病。特别是近几年来,由于养殖面积逐渐扩大,放养密度不断增加,近海水域污染日益严重,虾池老化,因而虾病的发生机率、流行面积和虾病种类,一直呈增长趋势。同时,发病季节越来越早,危害程度愈来愈大。目前全省已发现生物性
The prevalence of shrimp disease has become one of the limiting factors for the stable development of shrimp industry. 1 epidemic of shrimp disease The province began to see the incidence of shrimp farming in 1985. At that time artificial breeding of seedlings in Huanghua, Haixing and other places, the occurrence of trichomoniasis and bubble disease, severely affected the larval metamorphosis, and even led to a large number of deaths. Subsequently, various degrees of shrimp disease were found every year. Especially in recent years, due to the gradual enlargement of breeding area, increasing stocking density, increasing pollution in coastal waters and aging shrimp ponds, the probability of occurrence of shrimp diseases, epidemic area and types of shrimp diseases have been increasing. At the same time, the onset of the disease more and more early, increasing harm. At present, the province has found biological