Effects of different feeding strategies on the growth of young rainbow trout (Oncorhynchus mykiss)

Abstract

This study investigated the effects of different feeding strategies on the growth, conditions and food conversion rate of young rainbow trout (Oncorhynchus mykiss). The groups set up are as follows: a control group (Gc), which was fed every day for the week, a group with no feeding on Monday and Thursday (G_Mon-Thu), a group with no feeding on Saturday and Sunday (G_Sat-Sun), and a group that alternated feeding one day and no feeding the next (G_F-NF). At the end of the study, the mean (±SD) weight and food conversion ratio of groups were found to be: 83.51 ± 5.43 g and 1.09; 87.38 ± 5.95 g and 1.14; 83.50 ± 5.97 g and 1.15; and 76.66 ± 4.56 g and 1.26, respectively. Group G_F-NF showed significantly slower growth than the others, and it exhibited a higher food conversion ratio value than groups G_Mon-Thu and G_Sat-Sun (P<0.05). The condition factors of the groups were similar (P>0.05). This study showed that the two groups that did not feed for two days a week (G_Mon-Thu and G_Sat-Sun) did not exhibit negative growth performance, whether they were not fed on consecutive days or different days of the week, while group G_F-NF exhibited negative growth performance.

Key words: Rainbow trout, feeding strategy, food conversation rate.