Turkish Journal of Fisheries and Aquatic Sciences
2012, Vol 12, Num, 2 (Pages: 225-231)
Effects of Long-term Extended Photoperiod on Somatic Growth and Husbandry Parameters on Cultured Gilthead Seabream (Sparus aurata, L.) in the Net Cages
Hatice Vardar 1 ,Şükrü Yıldırım 1
1 Ege University, Faculty of Fisheries, Aquaculture Department, 35100 Bornova, Izmir, Turkey
DOI :
10.4194/1303-2712-v12_2_05
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In this study, the effects of the long photoperiod regime (15L:9D) on both somatic growth and husbandry parameters
were investigated in growing gilthead seabream (Sparus aurata). Experiments were conducted in high density polyethylene
(HDPE) floating cages which have net depths of 14 m and diameters of 20 m. They contained approximately 180,000 gilthead
seabream with average weights of 78.91±8.54 g and 71.39±4.06 g for experimental and control groups, respectively.
Additionally, artificial illumination was applied to experimental cages for 13 months, while it was not performed on the
control group. At the end of the experiments, fishes of experimental groups reached to 425.19±5.06 g on average (total
n=362,676), while this value was estimated as 305.42±25.01 g (total n=345,829) on average in control groups (P<0.05). In
addition, feed conversion ratio (FCR) was calculated as 2.04 and 2.37 for experimental and control groups, respectively,
however significant differences were found between these groups (P<0.05). Moreover, gonadal weight of fish in the control
group was significantly higher than the experimental group. Gonadosomatic index was recorded as 0.36 % in the control
group and 0.15 % in the experimental group (P<0.05).
Keywords :
Gilthead seabream, S. aurata, cage culture, long-term extended photoperiod, growth parameters, gonadal development