Compensatory Responses of Nile Tilapia Oreochromis niloticus under Different Feed-Deprivation Regimes

摘要

We investigated compensatory growth of Nile Tilapia Oreochromis niloticus in structural size and live weight in response to different deprivation periods and refeeding. Four treatments were assigned randomly to fish in 12 glass tanks, with each treatment performed in triplicate. The control group was fed to satiation three times a day throughout the experiment. The other three treatment groups were starved for 1 week (SI), 2 weeks (S2), or 4 weeks (S4) and then fed until the end of the experiment. After the experiment, no significant differences were observed among SI, S2, and the control group in average weight or length, whereas the weight and length of S4 were significantly reduced. Relative condition factors of the three starved groups decreasedsignificantly until the end of the restricted period but recovered rapidly after refeeding. The specific growth rate in weight (SGRW) of the three restricted groups recovered quickly upon refeeding and were significantly higher than the control group, but these differences disappeared gradually until the end of the experiment. No significant difference in specific growth rate in length (SGRL) was noted between the control group and the three restricted groups after refeeding. All three groups showed hyperphagia for a short period upon refeeding, and no statistical differences were observed in feeding efficiency among the four groups.