International Journal of Aquaculture, 2018, Vol.8, No.17, 127-136
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recorded for each fish when fish lost total equilibrium, its opercular movement rate was reduced and fish did not
respond to pressure on its body (S). Also, the time of recovery was recorded when fish started swimming in a
normal manner (R) (Table 1). Following recovery, fish were placed into maintenance aquarium and were observed
for 48 h for any adverse effects. Experiments were fulfilled using 15 fish for each species and stage in triplicate
(n=45).
Table 1 Stages of sedation and recovery employed in the current study for different types of anesthetics (Filiciotto et al., 2012)
Stage of sedation (short term)
Recordable behavior
S1
Loss of equilibrium
S2
Reduced response (loss of gross body movement)
S3
Losing response, fish can pulled from the posterior fin and reduced opercular movement
Stage of recovery
Recordable behavior
R1
regular operculum movement
R2
regular body movement
R3
complete equilibrium regained
1.3 Statistical analysis
The data was collected and entered into the personal computer. Statistical analysis was completed using Statistical
Package for Social Sciences (SPSS/version 17) software. The statistical test used as follow: mean and standard
deviation (mean ± SD) for sedation and recovery duration according to different anesthetic treatment in both
species, Mann Whitney test was applied for comparison between unpaired signed ranks test in respect to the
response of each anesthetic on both species at different stages separately, then applied to compare different doses
of anesthetic on separate species in different stages.
2 Results
2.1 The response of fish stage in both species to different anesthetics and recovery time variation
Variation in fish species showed significant differences in time duration for sedation using clove oil as an
anesthetic for adults and juveniles.
Mugil cephalus
recorded higher sedation and lower recovery times than that
recorded for
Sparus aurata
at all concentrations and stages (
p
≤0.001). Also, the minimal sedation time and
maximum recovery time were recorded at the highest concentration (25 mL
-1
) for both species. All durations were
showing a significant difference in both species using clove oil in sedation for juveniles and adult stages except
for the recovery time at (20 mL
-1
) for adults as time durations were showing insignificant differences (Figure 1).
Both species were responding, in the same manner, using MS-222 in respect to sedation and induction duration.
The maximum sedation time was recorded conducting the least (100 mL
-1
) concentration of MS-222 in
M.
cephalus
with a minimum recovery duration, while all sedation durations were lower in
S. aurata
and recovery
durations were higher than that recorded for
M. cephalus
for the entire concentrations (Figure 2). Sedation and
recovery duration at all concentrations were significantly different in both species at adult stage (
p
≤0.001). The
response of both species at juvenile stage showed insignificant difference using (50 mL
-1
) concentration at
sedation time, while, recovery duration was significantly different in both juvenile species at the same
concentration. Higher concentrations (75, 100 mL
-1
) of MS-222 showed significantly different sedation and
induction durations when conducted in both species at juvenile stage (Figure 2).
Both species at all stages were responding the same manner on conducting different concentrations of
2-Phenoxyethanol as
M. cephalus
recorded higher sedation and lower recovery times than that recorded for
S.
aurata
at all concentrations and stages. The response of adults of both species to induction was significantly
different on the conduction of (300, 400 mL
-1
) 2-Phenoxyethanol and was not significant using (350 mL
-1
)
concentration in both species. The sedation and recovery times recorded by juveniles of both species showed
significantly different durations on conducting (200, 250 mL
-1
) 2-Phenoxyethanol (
p
≤0.001), while, insignificant
sedation time was recorded when using (300 mL
-1
) of the same anesthetic at the same stage but showing
significant recovery time for both species (Figure 3).
