Categories
vol-31PREVALENCE AND HAEMOLYTIC ACTIVITY OF
AEROMONAS SPECIES IN LAKE EDKU AND
CONNECTED DRAINS
MOHAMED A. EL-SHENAWY
National Institute of Oceanography & Fisheries, Kayet Bay, Alexandria, Egypt.
Keyword: Aeromonas secies, fecal indicators, Lake Edku, Fishes, invertebrates.
ABSTRACT
During a year-long survey 2004, 80 water samples from Lake Edku and connected
drains as well as 44 fishes and invertebrate samples from Edku fish market were analyzed
for the prevalence of Aeromonas spp. (A. spp.) (qualitatively and quantitatively) as well as
for positive hemolytic activity. Fecal pollution indicators including Escherichia coli (EC)
and fecal streptococci (FS) and some environmental parameters including temperature (T),
salinity ‰ (S), pH and dissolved oxygen (DO) were also determined. All water samples
(100%) tested were positive for the prevalence of Aeromonas spp. in cfu counts ranged
between 0.6 x 102
and 28.0 x103
for water samples and between 0.5 x 102
and 8.0 x 103
for
fish and invertebrate samples with maximum in summer and minimum in winter. Strong
positive correlations were noted between Aeromonas spp. and both of E.coli (r = 0.85) and
fecal streptococci (r = 0.90). Also the same positive correlations between E. coli and fecal
streptococci (r = 0.81 to 0.97), were noted in all water samples. However a negative
correlation recorded in water samples of Lake Edku between salinity and each of
Aeromonas spp. (r = – 0.77), E. coli (r = – 0.79) and fecal streptococci (r = – 0.75). The
incidence of A.eromonas spp. were recorded in all water samples (100%) followed by
fishes (75%) and invertebrates (37.5%), however the percentage of haemolysin producing
Aeromonas spp. were found to be 65-70% in lake and drains water samples, and decreased
to be 57% and 31% in fishes and invertebrate samples respectively, which may pose a
potential health problem
