Ultrastructural alterations of cabrilla sea bass Serranus cabrilla liver related to experimental Gambierdlscus toxicus (dinoflagellate) ingestion

Abstract

Ultrastructural effects of dietary Gambjerdiscus toxlcus on the liver of cabrilla sea bass Serranus cabrilla were investigated. No fish treated with G. toxjcus died during the experiment. A marked perisinusoidal and intercellular fibrosis occurred after algal feeding. Microvilli decreased in number and shortened at the sinusoldal and canalicular areas of the hepatocytes. Lipid accumulation was also apparent. A high number of blnucleated cells, nucleolar disorganization and loss of condensed heterochrornatin at the periphery of the nucleus were also found, as well as nuclear pycnosis, dilated rough endoplasrnlc reticulum and swollen mitochondria. Thls work shows that toxins produced by this dinoflagellate may be considered to be harmful to fish through diet.