| Compensatory growth of mud carp(Cirrhinus chinensis Giinther) and mullet (Mugil cephalus Linnaeus), following 4 weeks of feed deprivation or ration restriction, were studied at Nan'ao Marine Biology Station, Shantou, China ,between December,2001 and March,2002. In the study, the control group was fed to satiation once a day during the 12-week experimental period. The other two groups were deprived or restricted from feed for 4 weeks and then were fed to satiation for 8 weeks. The blood, liver, and white muscle were sampled from six fish each time at weeks 0,1,2,4 in the period of feed deprivation or ration restriction, and at weeks 2,4,8 in the re-feeding period, respectively.The body length, entire length and body weight in mud carp and mullet were decreased but no significant compared with those in full ration during feed deprivation or ration restriction. These results showed that body length, entire length and body length were not good indices for nutritious condition of fishes. On the contrary, hepatosomatic index of the two fishes decreased significantly after one-week feed deprivation and ration restriction, which recover to the level of the feds only in two-week refeeding. The result showed that hepatosomatic index was very sensitive among body parameters in fishes. As for condition factor, there were significant difference in mullet but not in mud carp, which is probably due to the difference of body weight in the two fishes. During feed deprivation or ration restriction period, the SGR in mud carp is negative, indicating negative growth in mud carp, however after four-week refeeding, the SGR of starved and ration restriction group reach 1.1 0.2 and 1.06 0.26, respectively, much higher than 0.65 0.53 in the control group.It had been found that energy materials were used up in different levels after starvation or ration restriction, and different starvation or ration restriction time couldlead to different consumption.The content of plasma glucose, lipid at week 1, plasma protein at week 2 in mudcarp, and that of plasma glucose, protein at week 1, plasama lipid at week 2 in mullet decreased rapidly in the period of feed deprivation or ration restriction. After refeeding for 4 weeks, all biochemical composition in blood plasama were recovered to the levels of the fed controls. These results indicated biochemical parameters in blood were sensitive for feed deprivation or ration restriction.After starvation for one or two weeks, the content of the glycogen in liver and white muscle, and that of liver lipid decreased rapidly, however, the lipid content in white muscle and protein content in liver and white muscle had no significant difference from the controls. After re-feeding, all the above parameters in liver and white muscle were recovered to the levels of the controls. The phenomena had been found in mullet also. The results suggested that mud carp and mullet can take good advantage of glycogen, subsequent lipid as energy material.The hepatic ultrastructure in mud carp and mullet had some changes after starvation: the total number of cell organelles, the number of Rough Endoplasmic Reticulum and mitochondria decreased and the latter appeared atrophy and had all kinds of forms. In mud carp, the most significant difference compared with the controls was that the number of lysosome increased dramatically and almost all glycogen disappeared. In mullet, that was the number of lipid drops decreased significantly.After refeeding for 4 weeks, the quantity of cell organelle, Rough Endoplasmic Reticulum, glycogen and lipid rose again, however, the number of lysosome fell significantly. These phenomena demonstrated that the types, the quantities and the forms of cell organelles are closely related to the metabolism of hepatocyte.After feed deprivation or ration restriction for 1 week, the food conversion efficiency in mud carp was almost double of the control groups but the change of ration level was not significant. The results suggested that the mechanism of compensatory growth...
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