Quorum quenching bacteria protect Macrobrachium rosenbergii larvae from Vibrio harveyi infection

Abstract

In this study, we investigated the effect of N-acyl homoserine lactone-degrading bacterial enrichment cultures (ECs) on larviculture of the giant freshwater prawn Macrobrachium rosenbergii. The larval performance in terms of larval growth, larval survival, larval quality, duration of the larval rearing process and microflora levels in the rearing water as well as inside the prawn gut was investigated. The application of the EC bacteria was performed in two ways: by adding them directly into the larval rearing water and via enriched Artemia nauplii used for larval feeding. The results of the study demonstrated that both ECs that were tested had a similar positive effect on larval survival and larval quality, whereas they did not affect larval growth or the duration of the larval rearing process. Under normal hatchery conditions, the optimal EC densities were found to be 10(6) CFU ml(-1) for adding into the rearing water and 5 × 10(8) CFU ml(-1) for enrichment of Artemia nauplii used for feeding of the larvae. In the hatchery, the ECs can be grown on waste streams of Artemia hatching. Application of this kind of ECs could lead to a more sustainable aquaculture production, by replacing the use of antibiotics to control diseases.