Isolation and Identification of Bacteria found in the milt of cultured Clarias gariepinus


  • Gabriel Olarinde Mekuleyi Lagos State University
  • Folalu Adekunle Awe Department of Fisheries, Faculty of Science, Lagos State University, Ojo, Lagos State, Nigeria
  • Olusegun Olufemi Whenu Department of Fisheries, Faculty of Science, Lagos State University, Ojo, Lagos State, Nigeria
  • Olamiwaye Akintade Adeboyejo Department of Fisheries, Faculty of Science, Lagos State University, Ojo, Lagos State, Nigeria
  • Jesuyon Joseph Hungbo Department of Fisheries, Faculty of Science, Lagos State University, Ojo, Lagos State, Nigeria
  • Akanji Adeolu Akinyemi Department of Aquaculture and Fisheries Management, College of Environmental Resources Management, Federal University of Agriculture, Abeokuta, Nigeria
  • Olufunmilayo Adebimpe Olanloye Department of Pure and Applied Botany, College of Biosciences, Federal University of Agriculture, Abeokuta, Nigeria



Bacteria identification in fish is important; hence it provides update information on emerging and existing organisms thereby enriching the gene bank on fish disease. This study investigated bacteria associated with milt in cultured samples of African catfish- Clarias gariepinus. Catfish broodstock were collected from private Fish Farm in Ogun State, Nigeria. Fish samples were taken to the Microbiology laboratory, Federal University of Agriculture, Abeokuta Ogun State for milt microbial analyses, and amplicon were taken to International Institute of Tropical Agriculture, Ibadan for molecular characterization. Bio-edit was use for importing and mining nucleotide sequences into gene bank. The results revealed that the following bacterial organisms were present in the milt of Clarias gariepinus: Aeromonas caviae, Proteus mirabilis, Serratia rubidaea, Pseudomonas mosselii, Acinetobacter soli and Klebsiella variicola. The Basic Local Alignment Search Tools revealed the percentage similarity ranging from 86- 97.04% and their accession numbers. These bacteria indicated high levels of faecal contamination in the environment. In conclusion, bacteria were found in the milt of cultured catfish and are capable of being pathogenic to humans and may increase the vertical transfer to fry during breeding and rearing stage. 


Milt, Clarias gariepinus, bacteria, molecular method.


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