Stress resistance and dissolved oxygen improved by Microbubbles in RAS for Red tilapia

https://tis.wu.ac.th/index.php/tis/article/view/6251

Microbubble aeration has been recognized as a tool to improve dissolved

oxygen and fish culture performance in limited water aquaculture. This research

aims to investigate the effect of microbubble aeration on increasing dissolved oxygen,

fish culture performance, and stress resistance of red tilapia. The study used 3

treatments of aerations namely microbubble, blower, and without aeration with 3

replicates each. Red tilapia weighing 115.27±3.93 g were stocked in a plastic tank of

800 L water volume at density 50 individual/tank and cultured for 50 days in a recirculating

aquaculture system (RAS). Dissolved oxygen, fish culture performance, and stress resistance

were evaluated. Dissolved oxygen was monitored daily. In the middle of the research period,

a stress test was performed using different salinity at 12 and 24 ppt. Statistical analysis was

subjected to water quality, fish culture performance, and stressed resistance. The microbubble

aeration was able to stabilize DO level on 4.28 mg/L until the end of the experiment and suppressed

the CO₂ and ammonia content. Fish biomass was higher in microbubble treatment, with a lower

FCR value, lower stress level indicating fish in good health and promoting good culture performance.

HIGHLIGHTS

• The critical parameter of water quality in aquaculture is dissolved oxygen (DO) and to

increase its content is by aeration

• A nobel microbubble aeration was able to increase DO level higher than blower aeration

and stabilize DO at requirement level until the end of the fish culture

• The strong relationship of DO with fish hematology parameters those

more stable that indicate a lower stress level

• Stable physiological conditions and low stress of fish implied that the cultivated fish

is in good health and good performance by microbubble aeration