| In this paper, one year of southward farming Apostichopus japonicus was taken as theresearch object, to study the changes of physiological function under high temperature stress,heat stress, starvation and refeeding by pHysiological ecology methods, tested possiblecompensation growth pHenomenon and the influence of different cycles of hunger. The purposeof this experiment is to recover pHysiology and growth characteristics and mechanisms ofcompensation of japonicus after the changes of temperature stress. The results were as follows：1. The changes of digestion and immunity ability during thermal stress under watertemperature16±1℃to32±1℃was studied. breeding experiments of different temperaturestreatment were carried out to Southward sea cucumber of one age. This experiment setted3groups as parallel,1control group. Japonicus were used to experiment after domestication for14d, the initial temperature is16±1℃, then rise the temperature1℃every72h. rapidly extractgastrointestinal and body cavity fluid to detect the indicators when the temperature raised to16,18,21,24,27,30,32℃. At the end of the experiment we found that： during the hightemperature stress, the activity of alginate enzyme and amylase in the treated groups wassignificantly lower than the control group (P<0.05); the protease activity had no significantdifference between treated groups and control groups(P>0.05); the amylase and cellulaseactivity was significantly higher than the control groups at21±2℃(P<0.05), but in thesubsequent heating process continued their activities decreased rapidly and significantly lowerthan the control group (P<0.05). The results showed that： digestive capability of southwardfarming sea cucumber of one age significantly affected under heat stress, and decreased after22℃obviously. During the time of stress, pHagocytic killing activity and hemolytic activity of bodycavity of treated group increased slightly at20℃±2℃, significantly higher than controlgroup(P<0.05), and drop during the temperature raising process; superoxide anion andsuperoxide dismutase activity levels slowly declined during the in stress at31℃±1℃,significantly different with control group (P<0.05); the activity of acid pHospHatase and nitricoxide synthase fluctuated during stress, had no significant difference with control groups (P<0.05), didn’t show obvious characteristics. It is believed that an age japonicus digestive andimmune level have a certain relevance with temperature stress. The digestion and immunity levels of japonicus can be maintained at a high level between18to22℃, the reason may be thatyoung sea cucumber has a longer period to adapt, with higher adaptability to high temperaturestress, still could maintain some digestion and immune ability in order to ensure their healthygrowth during high temperature pHase.2. The compensation growth experiment studied the changes in the grows of sea cucumberduring restore to proper temperature after heat stress. This experiment setted4levels disposedthree parallel groups to each horizontal group, one control group, the average body weight was30.26±2.16g. Control the water temperature at28±1℃,conducted the test group japonicus for7,14,21,28d of heat stress, and then restore the water temperature to18±1℃, the total time foreach experimental group (the sum of the stress time and feeding time) were35d,42d,49d,56d,the control group fed algae powder and mud every day. Detected every index for each levelrespectively after refeeding7,14,21,28d. In this experiment we found that：under the conditionsof temperature18±1℃, body protein composition significantly lower than the control groups,but raised slightly at the end of this experiment, this might because of that they used protein asthe first energy souse in this progress. After different periods of heat stress, sea cucumber of eachtreatment group showed a significantly lower growth rate than the control group (P<0.05), andsome groups even showed negative growth. After different heat stress treatment, group japonicus14,21d relative growth rate is slightly higher, but the difference was not significant (P>0.05).And at the end of the experiment, the growth rate of the groups treated for14,21d were slighthigher than the controlled groups. This result sμggests that the growth rate of sea cucumber wasrestored, from significantly lower reaches relatively not significant levels, they may have somecompensatory growth capacity, and belongs to partial compensatory growth. During restoregrowth, the digestive and immune recovery speed in14,21d treatment groups were significantlydifferent from the7,28d experimental group and control group. Therefore, sea cucumbercomplete the compensatory growth process by increasing their intake and digestion capacity.Thispaper consider that during recovery pHase, the sea cucumber improve its digestive capacity tomaximize the use of food energy to complete growth, then appears compensatory growth. In thefour kinds of hunger cycle models, the compensation of the group treated for14d is the best;while21group the ability to compensate for the growth partly damaged because of longer highstress. Probably because of stress time is too longer, causing irreversible damage to the body ofthe group stressed for28d, causing unrecoverable damage to their ability of compensationgrowth. |
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