Vol 3 (1) 2011 - UBM :: Departamentul de Chimie-Biologie

Carpathian Journal of Food Science and Technology 2011, 3(1), 44-56
Also the persistence of
oxytetracycline at relatively high
concentrations in the sediments for a
significant period of time after medication
exposed the tilapia for highly residual levels
of oxytetracycline in their tissue [28].
The quantitative assessment of
oxytetracycline residual levels in the
examined tilapia samples were showed in
table (4). The incidence of oxytetracycline
detection in the examined samples of group
I, II and III were 100% (60), 93.33% (60)
and 53.33% (32) respectively. While the
concentrations of oxytetracycline residues in
the muscle of the tilapia were 319.92 ±
12.18, 142.14 ± 4.86 and 75.49 ± 1.66 ppb
for group I, II and III respectively. The
results of group I was agreed with the results
recorded by Bernardy [29] while that of
group II & III were lower. Also the obtained
results were lower than that recorded by
Choo [30]. The differences between the
obtained results and results of other studies
may be attributed to the variation in the
administrated dose whereas the high dose
leads to more rapid excretion than low [31].
It is result in an increase in the concentration
of the antibiotic in the environment
especially in the sediments [32, 28]. This
increases the building up of antibiotic [33]
and elongates antibacterial effects for 12
weeks within sediment after the cessation of
treatment [27]. Also the variation in the time
of samples obtaining, during or after the
withdrawal time (21 day) may affect in the
levels of antibiotic residues ([34, 13].
The abuse used of antibiotic either
extensive uses of antibiotic to treat fish
diseases nor added as feed additives in
aquaculture could results of hazards of
antibiotic residues, the antibiotic resistance
bacteria and resistance (R) plasmid in fish
and water microflora [35, 36]. Also the
presence of antibiotic in sewage and treated
water and the administration of animal
manure as feed could increase the potential
risk [34]; consequently produce fish
constitute potential risks to the consumers
[37, 38]. Such as increase the incidence of
foodborne infections due to their association
of antibiotic resistance enteric bacteria and
treatment failure in human [20].
European Commission Council
Regulation [39] set a standard permissible
limit of oxytetracycline residual level in fish
for human consumption. According to this
limit, 100% (60) and 80% (48) of the group I
and II were higher than the permissible
limits and unfit for human consumption,
while 13.33% (8) and 53.33% (32) of the
group II and III were under the permissible
limits and fit for human consumption. The
incidence of the examined samples under the
detection levels (