Compensatory growth response of rainbow trout Oncorhynchus mykiss Walbaum following short starvation periods

This sixty-day study was performed to determine the effects of short-term starvation and refeeding cycles on growth, feeding performances and body composition of rainbow trout(O ncorhynchus mykiss). Three hundred trout fingerlings with an average initial weight of 17.5±0.06 g were randomly distributed in 15 circular fiberglass tanks. The fish were exposed to 5 different feeding regimes; control: continuously fed twice daily to apparent satiation; T1 : starved for 1 day and re-fed for 2 days; T2 : starved for 1 day and re-fed for 4 days; T3 : starved for 3 days and re-fed for 12 days; T 4 : starved for 4 days and re-fed for 16 days. At the end of the experiment, growth performance, feed utilization, whole body ash and moisture contents were not significantly(P >0.05) different among the treatments. However, whole body protein content in T3 was significantly higher than other treatments(P <0.05). A significant difference in whole body fat content was observed between T3 and the control group at the end of the experiment(P <0.05). In conclusion this experiment suggests that feeding schedules involving starvation(1–4 days) and re-feeding cycles are a promising feed management tool for rainbow trout culture.