الفهرس 
Red sea characterization (nature)Only 14 pages are availabe for public view
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Abstract
The physicochemical parameters, water quality and abundance of bacteria were studied in Hurghada Red sea, Egypt , specially in two sites( Fishery port &National Institute of Oceanography and Fisheries) ( NIOF)). It was recorded there was an increase in the total bacterial counts (Fecal coliform, E.coli, Salmonellas) in summer compared to winter. The Fishery port being an active site for human activities, industrial , other wastes and run-off showed higher rate of fish infection (H. harid) compared to NIOF (14% versus 8% respectively). Although infected fish showed similar external signs (skin darkness, scales detachment, ulcers, small and large areas of haemorrhages distributed over many parts of the body) and internal signs of congestion, enlargement of internal organs especially liver, Spleen &Kidney and distension of gall bladder, the bacteria causing these symptoms were not similar.
It was suspected that Vibrio would be responsible for the most infections, however the Gram stain, biochemical and morphological and growth on media specific for Vibrio (TCBS) revealed that 60% of infection was caused by Vibrio while 40% was caused by other species.
To identify the bacteria causing fish infection, molecular characterization was carried out using PCR-based method for targeting 16S-23S rRNA intergenic spacer (IGS) regions among Vibrio species and 16S rRNA for other bacteria. The result of 16S-23S rRNA patterns resulted in identification of isolate (2) as Vibrio fischeri, isolates (3,9 and 10) as Vibrio cholera and isolates (7 and 8) as Vibrio sp. Moreover the 16S rRNA of four other species revealed that isolate1 was Vagococcus salmoninarum, isolate 4 was Carnobacterium maltaromaticum, isolate5 was Psychrobacter urativorans and isolate 6 was Psychrobacter celer. The Gram reaction indicated that 8 isolates were Gram –ve and 2 were Gram positive.
Growth on blood agar revealed that C. maltaromaticum was β haemolytic, whereas all other were non haemolytic.
The antibiotic sensitivity test of ten bacterial isolates revealed that most bacteria were sensitive to nalidixic acid 30µg, erythromycin 15 µg, ampicillin 10 µg, amikacin 30 µg, gentamycin 10 µg, ofloxacin 5 µg and streptomycin 10 µg, with exception of V. salmoninarum (isolate 1) and Vibrio sp.(isolate 8) which showed resistance to nalidixic acid 30µg, in addition Vibrio sp (isolate 8) also was resistance to ampicillin 10 µg and amikacin 30 µg.
To the best of our knowledge this is the first report in Hurghada red sea Egypt to report the fish infection with bacteria other than Vibrio, more over the infection with C. maltaromaticum which is β haemolytic bacteria seems to be alarming and need further investigations.