Fish Diseases and Management

6.1.3.4 Essential fatty acid deficiencies

Fish appear to be capable of synthesizing fatty acids of the w -7 and w -9 series but not the w -6 (linoleic) or w -3 (linolenic) series. The clinical features of deficiency are invariably associated with hepatic swelling due to severe lipid infiltration. There is consistent anaemia, associated with failure of the liver to secrete haemopoietin, and mortality is high.