Composition of psychrotrophic microflora of water and biofilter filler in recirculation aquaculture system on trout farm

摘要

The advancement of RAS technology and advantages over flow-through systems has led to increasing of Recirculating Aquaculture Systems (RAS) use. All the key biological mechanisms involved in RAS need to be better understood, especially those determining the development of bacterial populations and their interactions with fish. This study presents new knowledge on compositions of psychrotrophic bacteria community in various parts of RAS for rainbow trout growing, which constitute essential tools for system management. Pseudomonas, Alcaligenes, Acinetobacter, Aeromonas, Enterobacteriaceae, and also a small number of gram-positive bacteria and cocci were identified as dominant taxa of psychrotrophic bacteria in RAS biotopes. Microorganisms of the genera Pseudomonas, Alcaligenes, Acinetobacter and Aeromonas are the autochthonous microflora which forms an active microbial fiofilm on biofilter filler.