Global Journal of Fisheries Science Volume 7(1), pages 21-27, February 2025 Article Number: 72881F842 ISSN: 2782-750X https://doi.org/10.31248/GJFS2024.067 https://integrityresjournals.org/journal/GJFS Full Length Research Use of salt as a disinfectant in the treatments of bacteria found in eggs of cultured Clarias gariepinus (Burchell, 1822) F. A. Awe 1 *, E. A. Omogunwa 1 , O. A. Olanloye 2 and O. M. Ogunbanwo 3 1 Department of Fisheries, Faculty of Science, Lagos State University, Ojo, Nigeria. 2 Department of Pure and Applied Botany, College of Biosciences, Federal University of Agriculture, Abeokuta, Ogun State, Nigeria. 3 Department of Fisheries and Aquaculture, College of Agriculture, Lagos State University of Science and Technology, Ikorodu, Nigeria. *Corresponding author: Email: awefolalu@yahoo.com Copyright © 2025 Awe et al. This article remains permanently open access under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Received 22nd December 2024; Accepted 3rd February 2025 ABSTRACT: Egg disinfection is considered the most important routine work in hatcheries to avoid bacterial infection of fish eggs. This study assessed the use of sodium chloride (common salt) in the treatment of fish pathogens isolated from the eggs of Clarias gariepinus. Nine brood stocks of Clarias gariepinus were used. Their eggs were collected and taken to the International Institute of Tropical Agriculture (IITA) Nigeria for culturing, microbial analysis, DNA extraction of bacteria from the nutrient broth, and amplicon testing for molecular characterization. Bio-edit software was used for importing and mining nucleotide sequences into the gene bank. The molecular examination of Clarias gariepinus eggs showed the presence of four bacterial organisms namely: Staphylococcus succinus, Staphylococcus epidermidis, Bacillus subtilis, and Klebsiella pneumonia. Prior to common salt treatment, Staphylococcus succinus was the most predominant bacterial species isolated from the eggs of the fish sample with 84.88% similarity, Staphylococcus epidermidis followed closely with 81.66%. After the use of common salt, only Bacillus species and Klebsiella pneumonia were detected, with a similarity of 98.08% and 82.67%, respectively. Therefore, the common salt contributed immensely towards reducing the microbes and their nucleic acid contents in the fish eggs. Keywords: Abeokuta, broodstock eggs, cultured catfish, molecular characterization, Ogun State, salt. INTRODUCTION The African catfish Clarias gariepinus of the family Claridae is highly appreciated as a good aquaculture species because of its resistance to diseases, ability to tolerate a wide range of environmental parameters and high stocking densities under culture conditions, relatively fast growth rate, and good quality (Rahman et al., 2019). The aquaculture industry is the fastest-growing food- producing sector which accounts for approximately 50% of global fish production (Omeje et al., 2020). With the increased demand for fish, pisciculture has also increased to a great extent. However, due to the rise in fish culture, there has also been a rise in fish diseases (World Fish, 2018). Studies have shown high mortality rates and economic losses in catfish aquaculture due to infectious pathogens from bacteria (Adelakun et al., 2012). For oviparous animals, the survival of fertilized eggs is a critical component of reproductive success. Egg survival, in turn, can be strongly affected by various factors. Fish eggs, for example, are susceptible to predation (Van West, 2006) and pathogens such as bacteria (Phillips et al., 2008). The