Abstract: A study was conducted to evaluate the effects of five probiotics on the ecological security of sea cucumberApostichopusjaponicusjuveniles, including the tolerance to the probiotics, growth, immune enzymes of the juveniles and the regulation of culture water quality. The results showed that the tolerance of the five probiotics to the juveniles was found to be ranged in a descent order as group five>group one>group four>group three>group two. The tolerance of probiotics in group two was the minimum and the maximum in group five. There was no significant difference in specific growth rate of the juveniles in five probiotics (P<0.05), but significantly in the control group. The growth was enhanced by the probiotics. The enzyme (including SOD, LSZ and POD) activities in the juveniles were found to be promoted by the five probiotics compared with the control group (except for 0.5 mg/L in group one) significantly. The 24 h static water analysis revealed that the content of NO-2-N was the minimum at 48 h, then increased and DO<4 mg/L at 48 h. The content of dissolved oxygen level (DO) was found to be decreased gradually and the content of NO-2-N, NH+4-N in the control group increased. The 5 days nitrogen-infilling monitoring indicated that the content of NO-2-N, NH+4-N was higher in group one and group four than in other groups and the content of NH+4-N was more than 0.02 mg/L at 20 d. There was not significant in the content of NO-2-N, NH+4-N in difference groups in the first 20 days(P>0.05).
2012, Vol. 27 
