The influence of daily feeding frequency on growth and feed consumption of rainbow trout fingerlings (Oncorhynchus mykiss) reared at 18.5-22.5°C

Abstract

Feed consumption, growth and feed conversion ratios were studied in rainbow trout (Oncorhynchus mykiss) juveniles (mean weight 9.0±3.1 g) fed two, three or four times daily and reared at 18.5-22.5°C. The fish reached final mean weights of 26.8-31.6 g over the 40-day trial and growth rates (SGR) ranged 2.57-3.01% per day. Fish fed four times a day had a significantly higher SGR and final mean weight than those fed two or three times each day. Similarly, the condition factors of the groups fed three or four times a day were higher than that fed twice (p<0.01). Daily feed consumption rates (3.1-3.7% of the body weight) increased significantly with increasing feeding frequency (p<0.05), while differences in feed conversion ratios (1.06-1.16) were significant only between the groups fed two and three times (p<0.01). At water temperatures of 18.5-22.5°C, rainbow trout juveniles fed four times a day grow faster than those fed two or three times.