Molecular characterization of Aeromonas hydrophila isolates from diseased fishes in district Kasur, Punjab, Pakistan

Abstract

Pakistan is an agricultural country and fisheries play a very important role in the economic development of the country. Different diseases are prevalent in Pakistani fish but information related to the causative agents is not well-known. Keeping in view the significance of bacterial pathogens as the causative agents of multiple fish diseases, the present study was conducted for identification, characterization and analysis of virulence genes of Aeromonas spp. isolated from diseased fishes. A total of fifty fish samples having multiple clinical indications were collected from different fish farms of district Kasur, Punjab Pakistan. For isolation of Aeromonas spp. samples were enriched and inoculated on Aeromonas isolation medium. Isolates were identified and characterized by different biochemical tests, Analytical Profile Index (API) 20E kit and Polymerase Chain Reaction (PCR) assays. All isolates were screened for three putative virulence genes including aerolysin (aer), haemolysin (hyl) and heat labile cytotonic enterotoxin (alt). Seven isolates of Aeromonas (A.) hydrophila were retrieved and identified based on API 20E. These isolates were further confirmed as A. hydrophila on the basis of PCR assays. Three isolates were detected positive for the presence of virulence genes (alt and hyl). Whereas aerolysin (aer) gene was not present in any of A. hydrophila isolates. The present study confirmed A. hydrophila as the causative agent of epizootic ulcerative syndrome and motile Aeromonas septicemia in fish farms of district Kasur, Punjab Pakistan. Moreover, detection of two virulence genes (alt and hyl) in A. hydrophila isolates is a threat for fish consumers of study area.

Antimicrobial resistance profile of bacterial pathogens isolated from naturally infected fish in some lakes of Ethiopia

“…(P. fluorescens and P. putida) and K. oxytoca wererecovered from naturally infected Nile tilapia in El-Serw aquaculture fish farm of Egypt (Austin and Austin, 2016).The author also reported that the higher number of Aeromonas isolates commonly infect Nile tilapia than Pseudomonas isolates. A study on naturally infected fish in fish farms of district Kasur, Punjab, Pakistan found significantly virulent bacterial pathogens such as A. hydrophila from Nile tilapia (Tooba et al, 2021).…”

PREVALENSI Tubifex sp. YANG TERINFEKSI PARASIT DAN BAKTERI DI BPBAT TATELU, SULAWESI UTARA

“…Cacing Tubifex juga menunjukkan variabilitas yang cukup besar dalam kerentanan terhadap parasit Myxobolus sp melalui konsumsi myxospora (Lodh et al, 2011;Richey et al, 2018). Perkembangan dan penggandaan parasit terjadi di antara sel-sel epitel usus cacing Tubifex dan biasanya memakan waktu sekitar 2-3 bulan (Kusdarwati et al, 2017;Mandal et al, 2018;Tooba et al, 2024) sehingga spora triactinomyxon yang ditularkan melalui air (TAMs) dilepaskan ke air bersama kotoran cacing Tubifex. Infeksi pada cacing Tubifex dapat bertahan selama masa hidup cacing Tubifex dan pelepasan TAM dapat terjadi secara berkala selama rentang waktu setidaknya beberapa tahun.…”