A comparative research about rainbow trout (Oncorhynchus mykiss) fed with pellet and extruded feed

In this research, the effects of pellet feed that was prepared in a private rainbow trout farm and extruded feed that was produced in a private feed factory in Kastamonu on growth and development of rainbow trout (Oncorhynchus mykiss) were investigated. Live weight gain, specific growth rate, feed conversion rate and condition factor were calculated from the data obtained at the end of the experiment.Experiment was performed between the dates of June 7, 2009 to November7, 2009 (150 days in total). Water temparature was determined as 12.5 ± 0.28 oC in daily measurements. A total of 300 rainbow trout were stocked in the tanks and randomly allocated to four groups (75 individuals in each) in the experiment with duplicate groups. According to the groups, average initial weights of the fishes were 34.24±0.60 g for the firs group, 32.64±0.88 g for the second group (P>0.05). Fish in the first group was fed with pallet feed and the fish in the second group was fed with extruded feed for 150 days. In the experiment the amount of feed that was given to fish was calculated by reference table based on water temperature and average weights of fish.At the end of the experiment fish in the first group and the second group reached an average weights of 122.00±1.43 g and 279.00±2.22 g, respectively. Average weight gain was obtained 29.82 % for the firs group and 54.47 % for the second group. Specific growth rate was calculated as 0.88 % for the first group and 1.47 % for the second group. Feed conversion ratio for the first and the second group was obtained as 3.38 % and 1.60 %, repectively.Key words: Rainbow Trout (Oncorhynchus mykiss), Weight Gain Ratio, Specific Growth Rate, Feed Conversion Ratio, Condition Factor