The effect of two different feeds on the growths of rainbow trout (Oncorhynchus mykiss W. 1792) in net cages in the Black Sea

Abstract

This study was conduct to determine the effects of two kinds of feed, which were the different on unit price and contain of protein ratio, on growth in net cages for rainbow trout (Oncorhynchus mykiss W. 1792) in the Black Sea. The experiment was planned at the mariculture unit of Sinop Faculty of Fisheries, University of Ondokuz Mayis. for a period of 11 weeks. During the experiment totally 240 rainbow trout about 280 g in average weight were used. Two kinds of feed that used in the research which were consisted of 40 % and 45 % of protein ratios were not effected to growth parameters such as the live weight gain, condition factor and the feed conversion ratio for rainbow trout. It was found that live weight of trouts were as 702.01 g. 693.82 g and the food conversion rate were as 2.85, 3.14 and the conditon factor were as 1.47, 1.37 according to the cages which were arranged at the two different feeds. According to the results, feed with a protein ratio higher than 40 % sould not be necessary to use for bigger rainbow trout than 250 g. Besides this interpretation, it is excepted that ever feed mixture with the protein ratio of 40 % or less can be used for feeding of rainbow trout bigger than 250 g.