Effects of Compound Probiotics on Growth Performance, Muscle Quality and Aquaculture Water of Tilapia Under Zero-water Exchange Condition

【Objective】The study was conducted to explore the effects of compound probiotics on the growth performance and muscle quality of tilapia and aquaculture water environment under zero-water exchange condition, with a view to providing references for emission reduction as well as efficient and healthy aquaculture in fishery industry.【Method】Taking tilapia as research object and regular water exchange aquaculture mode as control group, a full-cycle aquaculture test of tilapia was carried out by adding compound probiotics under zero-water exchange condition (experimental group), and a comparative analysis on growth performance, muscle quality of tilapia and main water quality, microbial community structure was conducted.【Result】Under zero-water exchange condition, the survival rate of tilapia of the experimental group was 83.3%, significantly higher than the control group; feed coefficient was 2.3, significantly lower than the control group; as for the muscle quality, crude protein content of the experiment group was 22.17%, significantly higher than the control group. Main water quality of the experimental group stayed stable through the full-cycle of aquaculture period, the water temperature was 26.5-30.5℃, pH was 7.0-8.0, nitrite of water sample was 0.039 mg/L, significantly lower than the control group. The dominant bacteria was similar between experimental and control groups, however, the diversity index of the experimental group was higher than that of the control group.【Conclusion】Under zero-water exchange condition, adding compound probiotics in aquaculture water improved the survival rate of tilapia, reduced the feed conversion rate, and improved the muscle quality of tilapia. Meanwhile, the experimental group had strong improving effects on the water environment of aquaculture to some certain extent, and increased the diversity index of bacterial community. During the whole aquaculture production cycle, the zero-water exchange aquaculture of tilapia with high-activity compound probiotics had a good substitution effect for the conventional aquaculture model which relies on frequent water changes to release environmental pressure.