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Abstract

This study was conducted to determine the effects of various lengths of starvation periods on following compensatory growth (CG) in rainbow trout under summer conditions (18.1°C and day length of 12.5-14.5 hours). Five treatments with triplicate tanks were as follows: control (C) fed to satiation over 84 days; one (S1), two (S2), three (S3), and four (S4) weeks of starvation; and then refeeding for the remaining eight weeks of the experiment. Starvation periods induced hyperphagia during refeeding but only S1 and S2 were able to catch up with C. Repeated measures of analysis of variance suggested a convergence in body mass but not in body length (structure). Organo-somatic indices of the starvation groups were significantly reduced at the end of starvation periods and restored to levels of the control fish within the first two weeks of the refeeding period. Broadly speaking, starvation longer than one week significantly reduced apparent digestibility of dry matter, lipid, and energy compared with the control group but did not affect protein and ash, and a complete recovery in the digestibility coefficients occurred within two weeks of satiation feeding. There was a linear increase in body moisture and a decrease in lipid and lipid/lean body mass ratio with the severity of starvation periods, but these divergences largely disappeared at the end of refeeding. During the starvation period, the protein synthesis rate (estimated using RNA/DNA ratio in the muscle and liver) reduced but in subsequent refeeding period, it increased in starved fish. The findings of the present experiment suggest that an application of single starvation episodes to elicit CG as a management tool in summer conditions should not be longer than two weeks.

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“…In our study, protein efficiency ratios were affected by feeding regimes. PER values did not significantly change in single and multiple cycle fed Atlantic halibut (Heide et al, 2006), varied cycle fed olive flounder (Cho and Cho, 2009) and single cycle fed rainbow trout (Sevgili et al, 2013). However, some studies have reported that PER values were affected by feeding model during compensation growth, as is the case in our study (Ali and Jauncey, 2004;Cho et al, 2006, Eroldoğan et al, 2008.…”

“…*The first 10-day FI values of group G3 were not calculated because the group was in 10-day starvation group and not fed. et al, 2012;Sevgili et al, 2013). In this comprehensive study, both single and multiple starvation and refeeding cycles were applied and short and long term starvation periods were tested alongside each other.…”

The investigation of the effects of different feeding strategies on the growth of dolphin cichlid (Cyrtocara mooriBoulenger, 1902) fish

“…Similarly, in this study, hyperphagia was observed after 1 and 2 weeks of starvation. There are numerous studies reporting hyperphagia as the main mechanism of compensatory growth in fish (Blake, Inglis, & Chan, 2006;Boujard, Burel, Médale, Haylor, & Moisan, 2000;Dobson, & Holmes, 1984;Miglavs, & Jobling, 1989;Qian et al, 2000;Quinton, & Blake, 1990;Sevgili et al, 2013;Xiao et al, 2013).…”

“…In their study Yılmaz (2012) reported that there was no difference between the control group and other groups (B) and (C) in terms of feed conversion rates, and there was a difference between the groups of (D) and (E). In their study, in which they investigated the effects of starvations periods of different lengths on compensatory growth in rainbow trout, Sevgili et al (2013), applied the feeding periods of 1, 2, 3 and 4 weeks of starvation/8 weeks feeding. There was no difference between the values of feed conversion rates among these groups.…”

“…Weight gain, specific growth rate, feed intake, feed conversion ratio and survival rate were estimated using standard formulae outlined by Gümüş and Aydın (2013), Sevgili, Hoşsu, Emre, and Kanyılmaz (2013) and Adaklı and Taşbozan (2015):…”