Microbial assemblage of the anatomical parts of gercacinid crab from a tropical mangrove swamp

Abstract

The microbial assemblage and occurrence in the gut, flesh and shell of Cardisoma armatum, from the tropical mangrove swamp of Lagos Lagoon, Nigeria, was analysed using standard microbiological techniques. The crab gut had the highest total heterotrophic bacteria count and total coliform count with respective significant (p<0.05) values of 6.90 ± 0.16 x10⁴CFU g^-1 and 3.45 ± 0.12 x10²CFU g^-1. Total feacal coliform of the crabs were 0.05 ± 0.00 x10²CFU g^-1, 0.01 ± 0.00 x10²Cfu g^-1 and 0.01 ± 0.00 x102CFU g^-1 in gut, flesh and shell, respectively. Highest total fungal count of 7.50 ± 0.04 x103CFU g^-1 was recorded in the crab shell. The bacteria and fungi species isolated and their frequencies of occurrences in percentage were: Bacillus sp. (21.4 %), Citrobacter sp. (3.6 %) Enterobacter sp. (7.1 %), Escherichia coli (10.7 %), Klesiellia pneumonia (17.9 %), Providencia sp. (3.6 %), Serratia sp. (10.7 %), Staphylococcus aureus (10.7 %), S. epidermis (7.1 %), Vibrio sp. (7.1 %), Aspergillus flavus (8.6 %), Aspergillus fumigatu (5.7 %), Aspergillus niger (40.0 %), Fusarium sp. (14.3 %), Penicillium sp. (5.7 %) and Saccharomyces sp. (25.7 %). The isolation rates in the different anatomical sites of the crab follow the order: guts > flesh > shell and shell > flesh > guts for bacterial and fungi infestation respectively. The results of this study showed that the gercacinid crab, C. armatum in the tropical mangrove of Lagos harbours microorganisms including those that are pathogenic