바이오플락수 (Biofloc water)와 질화세균 및 이스라엘잉어, Cyprinus carpio nudus의 면역 반응

Abstract

Biofloc technology in recent time has obtained values in aquaculture management, both in water quality and feeding. Moreover, biofloc technology has potential to control pathogenic bacteria and improve immune response of cultured fish. This study was conducted to identify of heterotrophic nitrifying bacteria in biofloc water, and to investigate the effect of biofloc water on the non-specific immune response and physiological change of Israel carp, Cyprinus carpio nudus. The experiment was performed for 28 days. Heterotrophic nitrifying bacteria were isolated from biofloc water, and three species were identified by 16s rRNA sequence analysis; Acinetobacter bouvetii, Acinetobacter tjernbergiae and Lactococcus lactis. In tested groups, the values of ammonia-nitrogen were maintained stable until day 7. Total culturable bacteria count also had showed steady until day 7, and then the bacteria count increased continuously until day 28. The values of average body weight and length gain of tested fish were increased compared with those of control groups. The effect of biofloc water on the physiological parameters of tested fish showed no significant differences with the control group in the hematocrit, AST and ALT. But, gut mucus lysozyme activity and NBT reduction ability were significantly higher than control group on day 7.