Comparative Analysis of Pathogenic Bacteria Found on Skin and Gut of Labeo rohita Marketed in Nowshera, Pakistan

Abstract

Labeo rohita is one of the most often seen Indian major carp. The purpose of this study was to compare the pathogenic bacteria that were discovered on the skin and gut of Labeo rohita, which is sold in Nowshera, Pakistan. The fish sample was obtained in September 2024. The serial dilution approach was used to cultivate the bacteria, which was then distributed on prepared Muller-Hinton Agar media. Bacterial colonies were subjected to different morphological analyses, such as colony count, shape, and Gram staining, after the incubation. According to observation, the exterior bacterial count (11.3 x 10⁷ CFU/mL) was higher than the interior's (7.9 x 10⁵ CFU/mL). Nevertheless, other strains of bacteria could be distinguished at the genus level through biochemical tests. The discovered bacteria were Salmonella, Escherichia, Klebsiella, Staphylococcus, and Streptococcus. Among the microorganisms recovered from the targeted area, it was found that Salmonella was the most prevalent bacteria among the identified bacteria. Following Salmonella, Streptococcus and Escherichia were the next most prevalent bacteria. The least abundant bacterium identified was Staphylococcus. According to this research, fish contamination is mostly caused by Salmonella, Streptococcus, and Escherichia. Food and health inspectors should set up procedures for food handling and sanitation to verify the quality and cleanliness of fish. Additionally, customers are advised to use caution while choosing and buying seafood.

Keywords: Labeo rohita, pathogenic bacteria, serial dilution, morphological analyses, biochemical tests.