在贝类养殖中,牡蛎既可大批生产而且获利又高。但是,自从进入20世纪以来,世界各地养殖的和天然的牡蛎常大量死亡。主要原因是海水污染、赤潮、性腺过熟或尚未查清的其它因素。不过已经发现的许多疾病是其重要原因之一。现将其主要疾病概述如下。 In shellfish farming, oysters can be mass-produced and profitable. However, since the 20th century, farmed and natural oysters all over the world have often died in large numbers. The main reason is seawater pollution, red tide, overgrowth of gonads or other factors that have not yet been identified. However, many diseases have been found to be one of the important reasons. Now the main diseases are summarized as follows.