Biofloc-based farming of Indian white shrimp, Penaeus indicus, in recirculating aquaculture system (RAS) enriched with rotifers as feed supplement

A 2-month experiment on biofloc-enriched rotifer (Brachionus plicatilis)–based nursery farming of Penaeus indicus was conducted in a recirculating aquaculture system (RAS) of 6000-L-capacity fiber-reinforced plastic (FRP) tanks. The growth and production of P. indicus at a high density (PL10 at 2000 m−3) was compared and evaluated on RAS, hybrid RAS, and RAS with a biofloc-enriched rotifer system. Each treatment was kept in triplicates comprising the following: C, control (without RAS); T1, only RAS (RA); T2, RAS with biofloc (RA-BFT); T3, RAS with biofloc-enriched rotifer using an aquamimicry system (RA-BFTR); and T4, RAS with only rotifer (RA-R). B. plicatilis was provided at 10–20 nos mL−1. On completion of the experiment, the biofloc-enriched rotifer (RA-BFTR) showed improved growth (3.89 g) and survival (91%) compared to control (3.24 g, 85%). The immune parameters were significantly different from control to biofloc-enriched rotifer system. The PPO activity ranged in treatment animals from 0.068 to 0.11, and the highest value was recorded in RA-BFTR. Besides, the lysozyme activity also ranged from 0.061 to 0.12 (OD min−1). Total plasma protein also ranged between 60.51 and 92.57 mg mL−1. Total hemocyte cell count ranged between 4.11 × 106 and 7.52 × 106, and SOD inhibition was also significantly varied between 28.33 and 71. The highest SOD inhibition rate was observed in control and the least in RA-BFTR. It could be concluded that the nursery farming of P. indicus improved the growth, immunity, and survival in RAS with the biofloc-enriched rotifer system.