Application effect of tow kinds of probiotics on high-density breeding of Penaeus monodon

In order to determine the appropriate stocking density for the juveniles in the Penaeus monodon selective breeding program, the study designed indoor and outdoor aquaculture system to rear P. monodon larvae (PL15) for 40 days at the densities of 200, 300, 400 individuals/m2, respectively, added molasses every two days at 75% of the day feeding amount and two kinds of commodities probiotics (LSJW and BZT®BS), to compare the effect of two probiotics on the growth and survival of P. monodon and the regulation of water quality. Results showed that, with the stocking density increasing, the specific growth rate (SGR) and survival rate (SR) decreased in indoor group and outdoor group that used LSJW, the SGR decreased in outdoor group that used BZT 砸, while the SR decreased after the first rise. With the increase of stocking density and breeding time, the contents of NH4-N, NO2-N, NO3-N and PO43--P all increased, in which the indexes were the lowest in 200 individuals/m2 group and were the highest in 400 individuals/m2 group. Under the same density, NO2-N concentration in LSJW group was lower than that in BZT®group in indoor aquaculture system, NH4-N concentration in LSJW group was higher than that in BZT®group in indoor and outdoor aquaculture system. Key words: probiotics; Penaeus monodon; specific growth rate; survival rate; water quality