الفهرس 
Introduction and aim of workOnly 14 pages are availabe for public view
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Abstract
In the Gulf of Suez, Sepia savignyi is the most common species in the cuttlefish.
The age and growth of the cuttlefish S. savignyi caught by the demersal trawl
fishery in the Gulf of Suez were investigated during the fishing season 2014/2015.
Aging was determined by applying the Bhattacharya’s method (1967) based on
length frequency data for a sample of 452 ranged from (4.5 to 23 cm) for males
and (3.9 to 29 cm) for females in mantle length. The aging extends to three, four
and four years with zero groups of males, females, and sexes combined,
respectively. The mean von Bertalanffy growth parameters as estimated by four
different methods, L∞ were 24.28, 33 and 32.11 cm, W∞=1113.04, 2736.48 and
2523.47 gm. And k value were 0.61, 0.42 and 0.51/ year for males, females and
sexes combined, respectively. The sex ratio was 1:1.5 males: females. The size at
first sexual maturity (DML50) was 11.9 and 8.4 cm for females and males,
respectively. The GSI indices show that the females and males have two peaks in
the year-round spawning period where first of these is in April (3.5%) and (2.2%)
and the second is in December (4.1 %) and (2.4%) for female and male,
respectively. Five stages of gonad maturation were established for the females
and males, namely immature (I), maturing (II), mature (III), spawning (IV) and
spent (V) based on macroscopic examination. Oogenesis of oocyte demonstrating
seven stages of maturity in females were recognized oogonia, early primary
oocyte, late primary oocyte, previtellogenic oocyte, vitellogenic Oocyte,
advanced vitellogenic oocyte and ripe oocytes. Spermatogenesis of testes divided
into spermatogonia, primary and secondary spermatocytes, spermatid and
spermatozoa. The estimated value of total mortality, natural mortality, fishing
mortality and exploitation rate, Z=1.57/year,0.99. /year, 1.09 /year, M=0.32, 0.23
and 0.25/year, F= were 1.25, 0.76 and 0.84 /year and E =0.79, 0.77 and 0.77 /year
for males, females and sexes combined for Sepia savignyi, respectively.