biostudies-literatureUnknown25(1)Okasha LAAgricultural Research CenterThe production of striped catfish (Pangasianodon hypothalamus) has increased worldwide; recently, it was farmed with Nile tilapia in polyculture farms. Polyculture systems and water temperature (25℃ and 33℃) could affect Edwardsiella tarda infection, antibiotic efficacy, and residues. Moribund fishes were collected from three Farms 1-3: Farm 1 (monoculture, Nile tilapia), Farm 2 (monoculture, striped catfish), and Farm 3 (polyculture). Four E. tarda, LAMSH1, and LAMAH2-4 were isolated, whereas LAMAH3 was isolated from both fish spp., where striped catfish were highly susceptible to infection. The obtained E. tarda, which was isolated from striped catfish, has a significantly lower LD₅₀ than those retrieved from Nile tilapia, and co-infection occurred only in striped catfish on FBMC microbiology572https://www.ebi.ac.uk/biostudies/studies/S-EPMC12412243biostudies-literaturePresence of virulent Edwardsiella tarda in farmed nile tilapia and striped catfish.PMC12412243Okasha LAFarag EAHSherif AHSayed-ElAhl RMHfalsePresence of virulent Edwardsiella tarda in farmed nile tilapia and striped catfish.The production of striped catfish (Pangasianodon hypothalamus) has increased worldwide; recently, it was farmed with Nile tilapia in polyculture farms. Polyculture systems and water temperature (25℃ and 33℃) could affect Edwardsiella tarda infection, antibiotic efficacy, and residues. Moribund fishes were collected from three Farms 1-3: Farm 1 (monoculture, Nile tilapia), Farm 2 (monoculture, striped catfish), and Farm 3 (polyculture). Four E. tarda, LAMSH1, and LAMAH2-4 were isolated, whereas LAMAH3 was isolated from both fish spp., where striped catfish were highly susceptible to infection. The obtained E. tarda, which was isolated from striped catfish, has a significantly lower LD₅₀ than those retrieved from Nile tilapia, and co-infection occurred only in striped catfish on F2025-01-01T00:00:00Z2025 Sep2026-06-03T07:06:40.62Z2026-05-29T03:05:36.986ZS-EPMC124122434090849610.1186/s12866-025-04232-9