Nghiên cứu khả năng sử dụng Rong bún (Enteromorpha sp.) và Rong mền (Cladophoraceae) làm thức ăn cho Tôm thẻ chân trắng (Litopenaeus vannamei) trong mô hình nuôi kết hợp

Study  on  the  effect  of  feed  reduction  in  the  integrated  of  white  leg  shrimp  (Litopeneaus vannamei) with gut weed (Enteromorpha sp.) and blanket weed (Cladophoracea) on survival, growth and feed efficiency of shrimp was conducted. Experiment consisted of 7 treatments was randomly set up with three replicates. The control was fed commercial feed at libitum, other 6 treatments, shrimp were stocked with either gut weed or blanket weed and fed at 75%, 50% and 25% compared with the control. Shrimps postlarvae (0.036 g/PL) were placed in the 100-L plastic tanks (20 PL/tank, appoximately 60 PL.m-2) at salinity of 10 ppt. 100g of gut weed  or  blanket  weed  was  supplemented  during  culture  period.  After  72  days  of  culture, water quality in the terms of NH 3 /NH 4+ and NO 2- in the integrated treatments lower compared to  the  control.  Average  survival  of  shrimp  in  the  control  was  88.3%  which  was  not significantly different (P>0.05) from other treatments. Growth of shrimp of daily weight gain in the integrated culture with gut weed or blanket weed fed 75% satiation (0.103 and 0.101 g/day)  were  significantly  higher  than  the  control  (0.073  g/day).  The  highest  of  feed conversion ratio (FCR) was observed in the control (1.78) and were  significantly different (P<0.05)  from  other  treatments.  Protein  efficiency  ratio  (PER)  in  the  control  was  lowest (1.44) and statistically different from other treatments. These results show that Enteromorpha sp.  and  Cladophoracea  had  great  effect  in  the  growth  of  the  shrimp,  reduce  feed  costs, improve feeding and environment.