Characterisation of microbiological and physico-chemical properties of the ecosystems of freshwater snails (Lanistes libycus) in Upper Cross River Basin, Nigeria

Abstract

The microbiological and physico-chemical properties of the freshwater ecosystems of freshwater snails Lanistes libycus) from three sampling sites (Akaeze, Akpoha and Erei) in the Upper Cross River Basin of Nigeria were investigated. The freshwater samples were collected using pre-sterilized stoppered conical flasks for analyses. The mean total viable counts (TVCs) of the three sampling sites differed significantly (P=0.05) and ranged from 2.8 x 10⁵ to 57 x 10⁵ cfu ml^-1. The total coliform counts in Akpoha and Akaeze rice farming sites (19.0 and 18.0 MPN 100 ml^-1 respectively) were higher than that of the other site (Erei). The most prevalent bacteria isolated were Escherichia coli, Streptococcus faecalis, Pseudomonas aeruginosa, Vibrio parahaemolyticus, and Clostridium perfringens with Penicillium digitatum as the only prevalent mould. The mean temperature ranges from 28.40 to 29.10 0C, pH from 7.80 to 9.03 and salinity level from 1.06 to 1.68 ‰. The value ranges of the physicochemical parameters favoured microbial growth and diversity. However, the presence of the isolated microorganisms especially the food pathogens can enhance the susceptibility of this common seafood (L. libycus) in the area to microbial contamination during and after harvest.


Journal of Tropical Microbiology Vol.3 2004: 78-83