Location: Aquatic Animal Health ResearchTitle: Effect of different water biofloc contents on the growth and immune response of gibel carp cultured in zero water exchange and no feed addition system Author
|Zhang, Mingming - Yancheng Institute Of Technology|
|Qiao, Guo - Yancheng Institute Of Technology|
|Li, Ye - Yancheng Institute Of Technology|
|Qi, Zhitao - Yancheng Institute Of Technology|
|Li, Qiang - Yancheng Institute Of Technology|
Submitted to: Aquaculture Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/4/2018
Publication Date: 1/29/2018
Citation: Zhang, M., Qiao, G., Xu, D., Li, Y., Qi, Z., Li, Q. 2018. Effect of different water biofloc contents on the growth and immune response of gibel carp cultured in zero water exchange and no feed addition system. Aquaculture Research. 49:1647-1656.
Interpretive Summary: There is limited information whether biofloc technology (BFT) can be applied for intensive aquaculture for enhancing growth, increasing survival, improving immunity and reducing disease loss of cultured fish. The present study evaluated 1) whether gibel carp can uptake bioflocs, and 2) the effect of feeding bioflocs on growth performance and immune response of fish. Experiments were conducted under no food addition and zero-water exchange BFT system with different concentration of total suspended solids. The results demonstrated that bioflocs contained rich nutrients, and gibel carp eaten bioflocs showed higher weight gain and specific growth. In fish with bioflocs addition, the immune response was also enhanced significantly. The results demonstrated that bioflocs could be a dietary replacement for the commercial feed to reduce feeding prices and develop into a sustainable aquaculture method with improving economic efficiency. The study results provided valuable information on wider usage of BFT in aquaculture and new strategies for disease prevention by enhancing host immunity against fish pathogens.
Technical Abstract: This study evaluated the growth and immune response of gibel carp (Carassius auratus gibelio) cultured under no feed addition biofloc technology (BFT) system at different total suspended solid (TSS) concentrations (10, 300, 600, 800 and 1000 mg L-1 for group BF0-NF, BF300-NF, BF600-NF, BF800-NF and BF1000-NF) for 30 days. The results demonstrated that bioflocs contained rich nutrients, and gibel carp eaten bioflocs showed higher weight gain, specific growth and survival. Digestive enzyme activities such as pepsin and amylase increased significantly in BF300/600/800/1000-NF groups than those in BF0-NF group. Antioxidant response including superoxide dismutase and total antioxidant capacity in serum and skin mucus, was also enhanced significantly (p < 0.05). In addition, six immune-related genes were examined by RT-qPCR. Compared with BF0-NF group, expression levels of immune genes intelectin (ITLN), dual specificity phosphatase 1 (DUSP 1), keratin 8 (KRT 8), myeloid-specific-peroxidase (MPO), c-type lysozyme (c-lys) and interleukin-11 (IL-11) were up-regulated by 78.1-, 23.9-, 13.8-, 138.8-, 401.8- and 91.1-fold, respectively. The highest expression values were observed at TSS of 600-800 mg L-1. This study suggested that bioflocs can be uptaken by gibel carp as a food source, and have a potential to be used as a supplemental food for aquaculture.