Presence of Vibrios and Aeromonas Strains and Total Psychrotrophs in Hexagonal Spotted Grouper and Spanish Mackerel Fish PDF

Keywords

Vibrio, Aeromonas. Psychroupohs. Grouper. Mackerel

Abstract

This work was conducted on different parts of hexagonal-spotted grouper and Spanish mackerel fish from 10 major fishery shops in Riyadh City to assess the presence of vibrios and aeromonas using the API 20E and Biolog system. Also, pH and total psychrotrophs were assessed as two indexes of quality. Similar data were obtained from both identification systems except for Aeromonas media-like and Vibrio anguillarum which are not included in the API20E database. Aeromonas hydrophila, A. media-like, V. alginolyticus, V. anguillarum, V. damsela and V. fluvialis were recovered from fish samples with A. media-like and V. damsela most predominant. Unexpectedly, V. cholera and V. parahaemolyticus were not recovered. The number of skin samples of grouper having more than 7 log CFU/gm were much higher than that of mackerel skin samples. Similar psychrotrophic counts were noticed in gut samples of the two fish types, indicating similarity in growth habitat. Most of the grouper flesh samples had a pH in the range of > 6.40-7.02, whereas 95% of mackerel samples had a pH at 6.40 or below.