近年来，在集约化海水养殖中，肝脏肿大坏死病危害日益突出。5月份后，即进入该病高发期。病因：（1）链球菌等细菌感染引起；（2）饲料中毒引起；（3）长期大量使用抗生素等药物引起。症状：病鱼游动缓慢，分散于缓流处，浮于水面。病鱼体色发黑，鳃贫血，眼球充血肿大、突出 In recent years, intensive marine aquaculture, liver damage necrosis increasingly prominent. After May, that period of high incidence of the disease. Etiology: (1) Streptococcus and other bacterial infections; (2) caused by feed poisoning; (3) large quantities of antibiotics and other drugs caused by long-term. Symptoms: sick fish swimming slowly, scattered in the slow flow, floating in the water. Fish body color black, gill anemia, hyperextension, prominence