Comparision research on development and growth performance of originated in the mediterranean and the Atlantic Ocean Gilthead Sea bream (Sparus aurata L., 1758).

Aquaculture, the sector has grown rapidly for last decades, will be one of the most important sectors in the future. Our country is placed in an important lane in the world fish market especially by marine fish farming in last ten years. With Gilthead Sea bream, sea bass and about 20 other alternative species the Turkey's fish marketing also provided new opportunities for employment. Among the alternative species, it is now common to culture the different origins of same species. In this field, Gilthead Sea Bream (Sparus aurata Linnaeus, 1758) is the most applicable species. Commonly, the species lives in Aegean Sea, across all the Mediterranean Sea, western of Black Sea and cost of Atlantic Ocean may differ because of the some different ecological features of Aegean Sea and Atlantic Ocean. According to this, the fishes were grouped as A group of Atlantic Ocean origin, B group of Mediterranean and Aegean Sea origin and each group was stocked as 120.000 pieces in 2 cages each with 16 m diameter and 12-13 m depth. The trial lasted 19 months between June 2011 and December 2012. The study was determined according to the average of 400 g, which is accepted as the commercial body weight of the fish. The average live weight of the fish at the beginning of the experiment was found to be 4.24 ± 0.17 g for group A and 4.28 ± 0.19 g for group B. At the end of the experiment, it was measured as 415,32 ± 68,37 for group A and 374,03 ± 63,19 g for group B. The species (Sparus aurata) that indicates some genetic and morphological differences has been one of the popular species those cultured. Although there are some studies about the species' genetic and morphologic features, there is not any clear study about the growth or feed utilization. In this study, it will have worked those gilthead sea breams which are cultured in the same ponds and fed with same feeds by the ingredients. According to study evaluation of growth performances, digestion activities, genetic structures will have done. The gilthead sea breams those have come from two different regions are examined about the genetic structures. Fort his aim RAPD (Random Amplified Polymorphic DNA) analyses have been done, so genotypically parameter's differences are determined. The variations of groups were determined by calculating the allel frequencies and gut values. In conclusion the genotypic values are related to the differences of growth performances and the subject is more cleared. In the production period, it is concluded that, the gilthead sea breams from the Atlantic Ocean has grown better than the Mediterranean ones. In addition, FCR, SGR, CF, HSI, VSI values and mortality rates of the fishes were taken into consideration and no significant difference was observed in the results of the group. On the other hand, significant differences were found between the two groups (p <0.05). In general, growth performance of Group A fish was found to be better.