Major Bacterial Challenges Facing Nile Tilapia (Oreochromis niloticus) in Egyptian Fish Hatcheries

• DOI: 10.21608/javs.2024.259686.1304
• Publication Date: 2024-02-23T15:35:22Z
• Authors: Nourhan Elsayed; Khaled Fahmy; Mahmoud Abou-Okada; Awad Abdelbaky; Ahmed Eltahan; Alaa Eldin Eissa
• Keywords: Nile tilapia; Fish hatchery

Nile tilapia is the most farmed freshwater fish species across vast areas of African continent. Although Egypt considered largest producer tilapia, this has been faced with frequent episodes mortality at both hatchery and farm levels. In present study, we conducted field screenings to identify major bacterial pathogens responsible for these mass kills among broodstocks seeds in Egyptian hatcheries. Aeromonas hydrophila Streptococcus agalactiae were determined be threats hatchery-reared tilapia. The isolates presumptively identified using conventional biochemical tests API 20 NE miniaturized test. final identities retrieved molecularly confirmed PCR sequencing 16S rRNA genes. A. S. found sensitive florfenicol, while two exhibited resistance novobiocin ampicillin. oxytetracycline, whereas erythromycin. Histopathological examination livers infected revealed vacuolar degeneration necrosis hepatocytes. Remarkably, infiltrations Gram-positive cocci documented within hepatic parenchyma brain tissues. Further, edematous brains inflammatory cell infiltration through meninges. Severe retinal pathology, including collagen fibre disorganization, oedema, was also detected. current study emphasizes deleterious impacts some ubiquitous on health status their seeds. Ultimately, affirm that regular monitoring water quality, feed proper handling broodstocks, accurate diagnosis a crucial asset preventing disease spread