Bacteriological Assessment of African Catfish (Clarias gariepinus) Isolated from Earthen and Concrete Fish Pond

Abstract

The purpose of this research work is to evaluates, isolate, identify, characterized and compare the bacteria load in African Catfish (Clarias gariepinus) from Earthen and Concrete Fish Pond. African Catfish (Clarias gariepinus) is a choice culture fish and an African delicacy to African consumers. Concrete pond and Earthen pond are the two types of ponds used in fish farming in West Africa. An earthen pond is a water body that is enclosed by earth while a concrete pond are pond constructed with bricks (plastered) or tanks. Clarias gariepinus were obtained from the earthen and concrete ponds from Adekunle Ajasin University, Akungba–Akoko, Ondo state, Nigeria. The fishes were harvested and eviscerated and different organs of the fish were collected for the purpose of this research work. Isolation of bacteria was done using the streaking method of cultural media. Preliminary characterization of bacterial isolates were based on Gram staining, morphological and cultural characteristics. Further characterization was carried out with various biochemical tests (Catalase, Citrate, Indole, Oxidase test, Starch hydrolysis, Urease and Sugar fermentation) and Bergey’s manual Microbiology. In concrete pond, it was observed that Bacillus subtilis was the most percentage frequently distributed bacteria isolate in Clarias gariepinus with (8%) Staphylococcus aureus (9.5%), Alcaligenes xylosidans (4.7%), Alcaligenes paradoxus (4.7%), Acinetobacter calcoa ceticus (4.7%), Pseudomonas putida (4.7%), Bacillus cereus (23.8%), Citrobacter amalonaticus (9.5%), Acinetobacter baumanni(4.7%), Listeria grayi(9.5%) and Listeria monocytogenes (4.7%) while In earthen pond Enterococcus gallinarum (4.0%), Streptococcus ub eris (8.0%) and Micrococcus luteus(4.0%) was the most frequently distributed bacteria isolate in Clarias gariepinus earthen pond, Marinococcus halophilus(4.0%),Enterobacter aerogenes (4.0%), Micrococcus lylae (4.0%), Alcalige nes faecalis(4.0%), Enterococcus molodoratus (4.0%), Enterococcus gallinarum (8.0%), Bacillus pumilus (4.0%), Citrobacter freundii (4.0%), Sporosa rcina inulinus (4.0%), Deinococcus radiodurans (4.0%), Vibrio marinus(4.0%), Listeria murrayi (4.0%), Deinobacter grandis(4.0%), Deinococcus proteolyticus (4.0%), Bacillus lautus(4.0%) and Micrococcus halobius (4.0%). Highest viable colony counts (5.6 × 104 for C. gariepinus were found in the concrete pond and (6.3 × 104) from the earthen pond respectively. Alimentary canal of fish in the concrete pond has the highest value of 4.73±0.81a and fish body has the lowest values (3.53±0.99a).Fish water has the highest value (4.33±1.15a) and lowest value (2.20±1.2a)) were found in earthen pond. It can be concluded that this organisms isolated from C. gariepinus in this study has the potential of becoming pathogenic and dangerous health risk and constitute severe economic loss to fish farmers and general populate especially those that consume catfish, therefore the Catfish should be raised in an hygienic and properly processed methods before consumption.