A study of the bacterial types occurring on the skin and in the intestines of farmed plaice ( Pleuronectes platessa L.)

Abstract

Four small identical tanks fed with power station effluent were each stocked with 10 × “1-group” plaice. The fish in each of the tanks were fed minced fish containing different binding agents. Bacteria were isolated from skin and intestinal samples of two fish taken from each tank. Five generic/group generic types were isolated from fish skin while ten types were isolated from fish intestines. Organisms belonging to the Enterobacteriaceae were isolated from both skin and intestines. The types isolated from intestines also included Aeromonas species (spp.). However, strict anaerobes were unable to be isolated. All intestinal bacteria were tested for their ability to grow on a minimal salt agar medium containing each of the binders as sole carbon source. There was no special relationship between the binder to which the isolates were exposed in the fish intestine and the binders which they could utilise as sole carbon sources. Few isolates could utilise hydroxypropyl-methyl cellulose.