Histological Changes Observed in Glass Eel Liver during Starvation

During the course of an investigation of an epizootic occurred among glass eels** which were imported from Formosa as seed in the eel culture and stocked for a long time without feeding, the present authors noticed that not only diseased fish but also healthy ones had large empty spaces in their liver cells when observed in paraffin section. In some instances the majority of the liver cells were enlarged and had neither nuclei nor cytoplasm, the sections giving the appearance of a honey comb pattern. This kind of histological features of the liver had not been observed before either in glass eels immediately after collection at estuary areas or in those fully fed . These facts raised the following questions: 1) Whether these histological features are peculiar to the glass eels from Formosa. 2) Whether they are natural features following starvation or abnormal ones. 3) What the mechanism of development of the empty spaces is. Although several works have been done on cytological and cytochemical changes in fish liver during starvation1•`7), no mention has been made of the formation of empty spaces. The present study was undertaken to answer the aforementioned questions.