사육수조 내 Shelter가 붉바리 (Epinephelus akaara) 성장과 스트레스에 미치는 영향

Abstract

To enhance the efficiency of the breeding control of the red spotted grouper, Epinephelus akaara, this study investigated effect on the behavioral characteristics, growth and stress response of red spotted grouper, when providing a space hidden (artificial fish shelter) in a rearing tank, taking into account the ecological habits of the fish inhabiting the rock-bottomed areas. The shelter is manufactured with PVC tubes (length of 1,500 mm and diameter of 200 mm) and installed in a rearing water tank (3×3 m, circular PP) The first experiment was divided into the control group (no shelter), group I (two shelters), group II (four shelters), and group III (six shelters), and housed 100 fish (body weight, BW 130.0 ± 29.18 g and total length, TL 21.5 ± 1.39 cm) respectively. The rearing water is used by filtering natural seawater with a sand filter. The rearing conditions are dissolved oxygen (D.O) 7.72±0.57 and water temperature (WT) 18.9±2.5°C, and the circulation cycles of the rearing water is 3 to 4 rotations/day, and the commercial pellet was provided. The second experiment was divided into the control group (no shelter), group I (two shelters), group II (four shelters), and experimental groups II (four shells) and accommodated 70 fish (BW 257.0 ± 56.13 g , 25.9 ± 1.77 cm) respectively. The rearing environment condition is maintained at D.O 6.4±0.5 mg/L and WT 21±1.3°C, and the circulation number of the rearing water is 3 to 4 rotations/day, and the commercial pellet was provided. Most of the red spotted grouper's behavior in the rearing tank showed a tendency to form a group under the shelter. Although the weight of red spotted grouper tends to be high in a group II in the first experiment (p<0.05), in the second experiment, there was no differences TL and BW growth of fish in each experimental group. The corticotropin-releasing hormone (CRH) mRNA expression in the brain showed no differences in each experimental groups.

본 연구는 붉바리의 사육관리 효율성을 제고하기 위하여 암반지역에 서식하는 붉바리 생태 습성을 고려하여 사육 수조에 숨을 수 있는 공간(쉘터)을 제공하였을 때 붉바리의 행동 특성과 성장 및 스트레스에 미치는 영향을 조사 하였다. 실험 결과, 쉘터의 설치가 특이적인 성장증가 및 스트레스 변화에 미치는 영향은 나타나지 않았다. 하지만 쉘터 설치 후 붉바리가 쉘터에 숨어 은신하는 행동이 관찰되었으며, 쉘터의 설치가 붉바리에게 안정적인 사육환경을 제공 할 수 있을 것으로 생각된다. 추후 적정 사육 조건 수온 하 실험을 통하여 쉘터 설치가 붉바리의 사육조건에 미치는 영향에 대한 연구결과가 필요하다고 생각된다.