Effects of nitrosomonas and nitrobacter addition to water quality and shrimp growth performance in recirculating system

Abstract

This study applied 2 strains of Nitrosomonas bacteria (TB7.2) and strain of Nitrobacter bacteria (TV4.2) These strains were evaluated as two strains with the best protein conversion efficiency in 141 bacteria strains isolated previously. The experiment was implemented in two months from March to May, 2020. In this study, there were four treatments with 3 replicates per treatment. Treatment 1 was supplemented with Nitrosomonas bacteria at a concentration of 104 CFU/mL. Treatment 2 was supplemented with Nitrobacter bacteria with the same concentration. Treatment 3 was supplemented with Nitrosomonas bacteria and Nitrobacter bacteria with both concentration of 104 CFU/mL. The control treatment had no additional bacteria strains. Bacteria were provided regularly biweekly. Water parameters were measured every 7 days. The results showed that water parameters in the treatments 1, 2, 3 were significantly different compared to the control treatment (p<0.05). Survival rate (%) of whiteleg shrimp in treatment 3 was the highest value (970.010%) and were significant differences compared to treatment 1 (94.330.030%), treatment 2 (92.670.025%) and control treatment (81.670.040%). Therefore, both of bacteria should apply at the same time for the highest efficiency and this is also the potential for the development of probiotics based on these bacteria strains.