عزل وتحديد الطفيليات الخارجية عند أسماك المشط الأزرق Oreochromis aureus المستزرعة في محافظة اللاذقية

Abstract

The current study aimd to investigate the presence of external parasites in Blue Tilapia fish (Oreochromis aureus) farmed in Lattakia city, with samples were collected monthly from four fish farms affiliated with the General Commission for Fisheries Resources (Salah Al-Din Dam, The North Grand River Dam cages and lake, as well as a private farm in Deir Hanna, during the period between 15/3/2023 and 20/3/2024. As a result of examining the skin, gillis and nasal cavities of (120) fish samples, and two  genera of parasites: Cichlidogurus, Cyclopos and one species Dactyogyrus minutus were isolated  from the gills of O.aureus .

Results indicated that the highest prevalence of the three parasitic genera occurred during summer across all sampling locations. The genus Cyclopos exhibited infection rates the prevalence (66.66%) at Salah Al-Din Dam and (55.55%) at the Northen Big River Dam under extensive (free range)cultur, whereas it was not detecated in the privet farm. In contrast, The genus Cichlidogyrus was recorded at (100%) prevalence in both the cage system at the Northen Big River Dam and Deir Hanna private farm, but it was absent from Salah Al-Din Dam. Incidental infection with Dactylogyrus minutus was observed only at Deir Hanna private farm, where O.aureus were co-cultured with Common carp ( Cyprinus carpio) , reaching a peak prevalence of (33.33%) dueing the summer season.

These Findings provide baseline data on the distribution and seasonal dynamics of external parsites in cultured Blue Tilapia in Lattakia, which can inform enffective management and controlstrategies in aquaculture operation.