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2.1 Compensatory growth response following period of starvation in Sparus macrocephalusThe recovery growth experiment in Sparus macrocephalus with initial wet body weight of 101.9-172.7g following different periods of starvation was conducted in 20glass aquaria (0.8m~3/ aquarium). The experiment lasted for 40d for each test group. Group C, S5, S10, S15 and S20 were deprived food for 0d (control) ,5d, 10d, 15d and 20d, respectively. Then each group was refed ad libitum ration level for its rest experiment time. The main results were as followed: (l)There was significant difference between S5 and C in wet body weight during starvation period (P<0.05), and no significant difference existed between S10 and C ,S15 and C, or S20 and C, respectively (P>0.05); while in the recovery period, the difference between S20 and C was significant (P<0.05), no significant difference was existed between S5 and C , S10 and C, or S15 and C , respectively(P>0.05);(2)During the recovery period, there was significant difference in SGR between S5 and C, S10 and C or S15 and C , respectively (P<0.05); FR under S5 and S20 were significant higher than that of C(PO.05); and FCE under S5, S10 and S15 were also significant higher than that of C (P<0.05); (3) There were significant different in water content between S10 and C, S15 and C, or S20 and C, respectively (P<0.05); protein significant difference existed between S5 and C, or S10 and C(P<0.05); and ash content was significant difference between S10 and C(P<0.05); there were also significant different in lipid between S5 and C, S15 and C, or S20 and C, respectively (P<0.05). These results indicated that there was completely or partly compensatory effect in the recovery growth in Sparus macrocephalus by means of increasing feed intake (FR) and food conversion efficiency (FCE). Sparus macrocephalus mainly depend on lipid as its energy consumed during the starvation period, protein content within fish increased slightly, while lipid content was decreased, and no morn changes were occurred in water and ash content after the recovery period.
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