Polyculture of Sea Cucumber Holothuria scabra with Pacific White Shrimp Litopenaeus vannamei

An experimental study of polyculture of sea cucumber Holothuria scabra with Pacific white shrimp Litopenaeus vannamei was carried out in the laboratory. Results indicated that nutrient structure of the culture system was influenced significantly by the sea cucumber: the phosphate and nitrate concentrations were enhanced more obviously in the polyculture system (PS) than in the monoculture system (MS), but by contrast, the ammonium concentration remained low in the PS. The sulfide contents of the sediment were reduced in the PS to 10.32 +/- 1.85mg/kg, accounting for about 2/5 of that in the MS. The PS of sea cucumbers had positive effects on the growth and survival of shrimp, the specific growth rate of weight of shrimp in the PS was 2.89 +/- 0.63%/day and significantly higher than that of the MS (average 2.05 +/- 0.57%/d). Survival rate of the shrimp in PS was 79.3 +/- 22.9%, dramatically higher than that of the MS (average 64.0 +/- 17.5%). In the PS, the shrimp had no negative effect on the sea cucumbers who ingested and assimilated food residue in the sediment of the culture system with an assimilation efficiency of 42.06 +/- 10.62% for organic matter. PS of sea cucumber Holothuria scabra in the shrimp culture system had both environmental and economic benefits. This PS method could contribute to sustainable development of aquaculture in China.