International Journal of Aquaculture, 2016, Vol.6, No.6, 1
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growth phase and secondary growth phase. Also, these two phases were investigated by many authors (EL-Gharabawy,
1996). The role of the follicle cells in the oocytes is to form an active part in the transfer of proteins and other nutrients
from the blood to the developing egg as reported by (Zaki and El-Gharabawy, 1991; El-Gamal, 2003; El-Halfawy et al.,
2007).
Figure 8 Mean gonadosomatic index (GSI) of female
L.carinata
in Suez bay
Figure 9 Monthly changes in concentration of 17β-Estradiol,
Testosterone levels and GSI of female
L.carinata
in Suez bay
Table 1 Monthly concentration of 17β – Estradiol, Testosterone levels and GSI of female
L.carinata
in Suez bay
Months
F GSI ±SE
17β-Estradiol ng / ml
Testosterone ng / ml
Nov-12
7.056 ±0.729
0.199
29.7
Dec
8.883 ±0.867
0.102
30.5
Jan 2013
6.223 ±0.669
0.113
19.9
Feb
1.416 ±0.377
0.116
17.4
Mar
0.623 ±0.179
0.122
18.3
Apr
0.467 ±0.062
0.123
20.6
May
0.397 ±0.047
0.138
21.3
Jun
0.921 ±0.091
0.142
23.6
Jul
1.338 ±0.156
0.152
24.8
Aug
1.477 ±0.367
0.168
25.9
Sep
3.864 ±0.437
0.187
26.1
Oct
5.161 ±0.513
0.192
26.9
First phase of oogenesis in
Liza carinata
is similar to the pre - maturation period
Liza ramada
of (Zaki and
EL-Gharabawy, 1991). This phase correspond to the pre - vitellogenesis stage in red mullet (
Mullus barbatus barbatus
)
of (Lambros et al., 2014). Yolk nucleus appeared at the end of late peri - nucleolus stage similar result was indicated by
(Sung et al., 2004).
Second phase of oogenesis in
Liza carinata
corresponds to the vacuolization period in
M. cephalus
of (Assem et al.,
2008). The beginning of yolk deposition is an indication of the phase of vitellogenesis (El-Gamal, 2003; Ramadan,
2010), the trophoplasmic growth period (Latif and Saady, 1973), the primary, secondary and tertiary yolk stage and the
yolk formation stage (Zaki and EL-Garabawy, 1991; Ramadan, 2010). At the ripening of oocyte in
Liza ramada
, the
migration of the nucleus to animal pole occurs. The yolk deposition in the oocytes of the present species shows the
same feature as described by other authors (Zaki et al., 1986; Zaki, 1989; Zaki and EL-Garabawy, 1991).
These results are concomitant with the previsous studies performed on
Caranx crysos
and
Pagellus erythrinus
by
(Assem, 2000; Assem, 2003
)
and with (Abou-Seedo and Stephen, 2004) for
L.klunzingeri,
and with some different from
(
Mahmoud, 1997) that detected the immature ovary month later from June to August in the same species.
In this study spawning season of female
Liza carinata
detected from November to March and this result agreed with
(EL-Boray, 1993; Hakimelahi et al., 2011) for the same species but also with (Moacir et al., 2011) in another species
M.
