Conventional aquaculture faces declining productivity, shifting to recirculating aquaculture system (RAS), known for minimizing water usage and maintaining consistent water temperatures for year-round fish growth. Rainbow trout (Oncorhynchus mykiss), a globally important cold-water species and the third most farmed fish in inland waters of Korea, valued for its fecundity and rapid growth. Dissolved oxygen, an important environmental factor affecting fish production and economics, highlights the need for smart aquaculture practices. Since 2018, the rise of intelligent aquaculture platforms, incorporating information and communications technology (ICT), emphasizes the essential role of RAS implementation. This eight-week study aimed to determine the optimal dissolved oxygen concentration for rainbow trout in RAS, utilizing a device for continuous monitoring, control and record. Dissolved oxygen concentrations were set at 5-6 mg/L, 9-10 mg/L, 14-15 mg/L and 17-18 mg/L. The growth rate significantly decreased at 5-6 mg/L, with no significant differences in other experimental groups. In hematological analysis, growth hormone (GH) was significantly highest at 5-6 mg/L, followed by 9-10 mg/L while Insulin-like growth factor-1 (IGF-1) was significantly lowest at 5-6 mg/L. In conclusion, the optimal dissolved oxygen concentration for rainbow trout in RAS is approximately 9-10 mg/L. Higher concentrations do not contribute to further growth or profitability.

서 론
재료 및 방법
    사육 시스템
    실험 어류 및 실험 조건
    수질 분석
    혈액학적 분석
    통계 분석
결 과
    어류의 성장 및 생존율
    수질 분석
    혈액학적 분석
고 찰
결 론
사 사

• 박근홍(부경대학교 대학원 수산생물학과 대학원생) | Kunhong PARK (Graduate student, Department of Fisheries Biology, Pukyong National University, Busan 48513, Korea)
• 최진서(부경대학교 양식응용생명과학전공 학생) | Jinseo CHOI (Student, Department of Aquaculture and applied Life Sciences, National University, Busan 48513, Korea)
• 이영훈(부경대학교 대학원 수산생물학과 대학원생) | Younghun LEE (Graduate student, Department of Fisheries Biology, Pukyong National University, Busan 48513, Korea)
• 박정환(부경대학교 양식응용생명과학전공 교수) | Jeonghwan PARK (Professor, Department of Aquaculture and applied Life Sciences, National University, Busan 48513, Korea) Corresponding Author