STUDY ON PHOTOSYNTHETIC BACTERIA AS LIVING FEED IN AQUACUTURE BREEDING

Abstract

For  diversity  of  living  feed  sources  in  aquacultare  breeding,  we  estimated  nutritional  values  of  several photosynthetic  bacteria  sttains  (PSB). The biomass  of  four  chosen  PSB  sttains  contained  amounts  of  amino

acids  (including  essential  amino  acids  like:  phenylalanine,  isoleucine,  leucine,  lysine),  total  lipids  and monounsaturated  fatty  acids  higher  than  in  Chlorella sp.  and  Nanochloropsis sp., but  polyunsaturated  fatty acids  (such  as  EPA,  DHA)  were  not  found  in  among  of  them.  We  used  them  as  living  feed  for  rotifer Brachionus plicatilis  and  bivalves.  For  B. plicatilis,  the  density  increased  similarly  when  fed  on  PSB  and microagale  after  9  days  (from  28  ±  3  and  27  ±  4  individuals/ml  to  83  ±  5  and  85  ±  4  individuals  /ml, respectively).  The  survival  ratio  of  Meretrix meretrix  fed  on  PSB  were  also  comparable  to  those  fed  by microagale (in two stages of age: from 0 - 8  days and from 8-12  days). Crassostrea sp., had the same size and paedomorphosis  time from sfraight-hinged  to  advanced  umbone  stage  when  fed  on  PSB  and  microagal,  the survival  ratio was  65.3 ± 6.5% and 66.9 ± 4.5% , respectively. For Lutraria sp., from sttaight-hinge  to very early umbone stage, paedomorphosis time and size were similar when fed on PSB and microgale. These feeds

were experimented on Lutraria sp 25 days of age, their survival ratios were approximate value. From obtained results, we  suggest  that biomass  of  chosen  PSB  sttains  can be  used  as  living  feed  to  supplement  or replace

biomass of microalgae in aquaculture breeding.