본 연구는 양식산 참돔과 넙치를 Cochlodinium polykrikoides 적조에 노출시켜 노출 시간에 따 른 생존율, 호흡수, 혈중 스트레스 지표 및 조직학적 변화를 비교 조사하였다. 대조구는 자연해 수를 사용하였고, 실험구는 C. polykrikoides 밀도를 5,500±200 cells/ml로 설정하였다. 그 결과, 참돔은 적조 노출 1시간 이내, 넙치는 적조 노출 5시간 이내 전량 폐사하였다. 생리학적 반응 을 분석한 결과, 참돔은 적조 노출 후 혈중 Glucose 농도가 감소하였으며, 혈중 GOT 및 GPT 농도는 증가하였고, 혈중 SOD 농도는 감소하고, CAT 및 GPx 농도는 증가하는 경향을 보였다. 넙치는 적조 노출 후 혈중 Cortisol 및 GOT, GPT 농도가 증가하였고, 혈중 Glucose 농도는 적조 노출 1시간째 증가한 이후 감소하였으며, 혈중 SOD, CAT, GPx 농도는 노출 1시간째 감소한 이후 증가하였다. 조직학적 분석 결과, 참돔과 넙치의 아가미에 구조적인 손상이 발생하였다. 결론적으로 5,500 cells/ml 밀도의 C. polykrikoides 적조 노출은 양식산 참돔과 넙치에게 산화 적 스트레스로 작용하여 체내 항산화 방어 기작을 활성화하고, 간과 아가미의 손상을 발생시 키는 것으로 나타났다.

In this study, using a continuous behavior measurement technique, the short-term behavioral responses and tolerance limits of red seabream Pagrus major fingerlings to sudden exposure to low salinity in a controlled environment were observed. The activity of the fingerlings suddenly exposed to 21.4, 17.3, and 9.8 psu increased temporarily at the initial exposure to show irregular swimming behavior, but then recovered a stable activity pattern through rapid salinity adaptation. However, the organisms suddenly exposed to 7.3 and 4.3 psu could not withstand the salinity stress, and their swimming behavior was severely disturbed and all individuals died within 48 hours. The findings suggest that red seabream underwent a temporary salinity stress process at the beginning of the exposure to concentrations of 10.0 psu or higher. At these concentrations, osmotic control was possible within at least 11 hours, so stable metabolic activity was also possible. However, organisms suddenly exposed to concentrations below 5.0 psu exceeded the tolerance to low salinity and the sublethal limit. In red seabream exposed to this concentration range, severe behavioral and metabolic disturbances were observed, and death was observed due to osmotic control failure. In conclusion, a salinity range of 5.0 to 10.0 psu can be predicted to correspond to a concentration range in which the osmotic control ability of the red seabream fingerlings is lost, and sub-lethal reactions occur.

In order to collect basic information of response behavior of red seabream (Pagrus major) during pilling, works for constructing wind power station in Byeonsan Peninsular, Korea were investigated. Four cultured red seabream CRB1 to CRB4 [total length (TL): 27.1 ± 1.0 cm; body weight: 359 ± 30 g] were tagged with an acoustic tag and used in experiment. CRB1 and CRB2 to CBR4 were released on the sea surface at same time around the constructing site of the wind power plant on September 22, 2017 and July 18, 2018, respectively. The tracking of the CRB1 to CRB2 and CRB3 to CRB4 were conducted for two hours, approximately, using VR100 receiver including a directional hydrophone and VR2W receivers array consisted of 19 presence/absence receivers (VR2W receivers), respectively. The underwater noise level before (no pile driving works) and during pile driving works was measured 116.0-118.0 dB (re 1Pa) and a maximum of 160 dB (re 1Pa), respectively. CRB1 moved about 6.0 km with average swimming speed of 80.2 ± 20.5 cm/s for 2.1 hours without pile driving work. The average water depth of the sea bed on the route of CRB1 was 9.1 ± 0.4 m. CRB2 moved about 7.3 km with the average swimming speed of 96.8 ± 27.1 cm/s for 2.1 hours with pile driving work. The water depth of the sea bed on the route of CRB2 was 11.9 ± 0.6 m. At results of the Rayleigh’s z-test two fishes CRB1 and CRB2 showed significant directionality in the movement (p < 0.01). Movement mean angles of CRB1 and CRB2 were 92.7 and 251.8°, respectively. CRB2, CRB3 and CRB4 exhibited the escaping behavioral response from the noise of source during the pile driving work. The swimming speed of the CRB2 exposed on the heavy underwater noise stimuli due to the pile driving work was 1.21 times faster than that of the CRB1 exposed on the ambient underwater

참돔은 등쪽에 푸른 반점이 흩어져 있고, 홍민어는 꼬리 쪽에 검은 점이 있어 원물 형태는 쉽게 구분할 수 있다. 그러나 횟감이나 필렛으로 이용 시 참돔과 홍민어를 구분하기 어려워, 참돔의 종 특이 primer를 개발 및 검증하고 모니터링을 통해 참돔의 위변조 사례를 조사하고자 하였다. 시료에서 gDNA를 추출하여 PCR을 진행하였으며 참돔 primer의 product size는 468 bp, 홍민어 primer의 product size는 181 bp으로 설계하였다. Multiplex PCR 결과 참돔과 홍민어에 대한 종 특이적 증폭이 확인되었다. 또한, 참돔과 홍민어 PCR 민감도 실험 결과 참돔 primer는 1 ng, 홍민어 primer는 0.1 ng 까지 밴드가 확인되었다. 모니터링 결과 참돔으로 구매한 시료 19건 모두 참돔으로 판정되었다. 따라서 본 연구에서 제작된 참돔과 홍민어 종에 대한 종 특이적 primer는 횟감 등 수산물에도 적용할 수 있어 현재 유통 및 판매되고 있는 참돔 및 홍민어 판 별에 적합성을 확인하였다.

IL-1RAcP는 일명 interleukin-1 receptor accessory protein이라 칭하며 interleukin-1 염증성 사이 토카인과 interleukin-1 receptor I (IL-1RI) 결합체와 복합체를 형성하여 작용한다. IL-1RAcP는 면 역반응, 스트레스 및 세포사멸과 관련이 있다. 본 연구의 목적은 참돔(Pagrus major)을 저수온 (8℃, 33 psu) 및 저염분(20℃, 10 psu) 상태에 노출시킨 후, IL-1RAcP 유전자의 발현을 관찰하는 것이다. 연구결과, IL-1RAcP 유전자의 발현은 저수온(8℃, 33 psu) 및 저염분(20℃, 10 psu) 상태 에서 유의적으로 증가하는 것으로 나타났다. 이 연구결과로서 IL-1RAcP 유전자는 저수온 및 저 염분 등의 환경 스트레스에 대한 생체지표유전자로서 역할을 한다고 제의한다.

FK506BP는 일명 FK506 binding protein 12이라 불리는 작은 펩티드로서 single 도메인을 가진 다. FK506BP는 면역반응 억제, 산화적 스트레스 및 염증과 관련이 있다. 본 연구의 목적은 참돔 (Pagrus major)을 저수온(8℃, 33 psu) 및 저염분(20℃, 10 psu) 상태에 노출시킨 후, FK506BP 유 전자의 발현을 관찰하는 것이다. 연구결과, FK506BP 유전자의 발현은 저수온(8℃, 33 psu) 및 저 염분(20℃, 10 psu)상태에서 유의적으로 증가하는 것으로 나타났다. 이 연구결과로서 FK506BP 유전자는 수온 및 염분 등의 환경 스트레스에 대한 생체지표유전자로서 역할을 한다고 제의 한다.

We determined the effects of different water temperatures (15, 20, and 25℃) and photoperiod cycles (24L:0D, 12L:12D, and 0L:24D) on the oxygen consumption of the offspring of a cultured Japanese strain (JJ), a selected Korean strain (KK), and intraspecific hybrid strains (JK and KJ) of red seabream, Pagrus major, under starvation conditions. The different fish strains, water temperatures, and photoperiod cycles had effects on the mean oxygen consumption of fish. Oxygen consumption increased with increasing water temperatures for all photoperiod treatments (p <0.001). Fish held in continuous darkness (0L:24D) used consistently less oxygen than fish exposed to continuous light (p <0.05). The oxygen consumption of fish exposed to the light phase in a 12L:12D photoperiod was higher than that of fish in the dark phase of the 12L:12D cycle, and differences were significant in three of the strains: JJ (15℃), KK (15 and 20℃), and KJ (25℃). The oxygen consumption of the inbred (JJ and KK) and intraspecific hybrid (JK and KJ) strains varied with differing water temperatures and photoperiod cycles. The JK strain displayed significantly higher oxygen consumption than the other strains under all experimental conditions except 15℃ with a 0L:24D photoperiod. The JK and KJ strains usually showed the highest and lowest oxygen consumption values, respectively, whereas the inbred strains exhibited intermediate values. Oxygen consumption in the JJ and JK strains was usually higher than that of the KK and KJ strains. We propose that differences in the thermal sensitivity and photosensitization properties of the strains contribute to differences in their ability to adapt to changes in water temperature and photoperiod, thus resulting in differences in the amplitude of their metabolic rates.

The food components of red sea bream(Pagrus major) cultured in copper alloy(brass) net(BN) and nylon net(NN) cages for nine months were investigated. The body weight was 234.9g at the beginning of the culture(the young fish), and then 692.1g(BN group) and 549.3g(NN group) at the fish cultured for nine months(the nine-month culture fish). The moisture content of the edible portion of the fish was higher in the young fish than in the nine-month culture fish. On the contrary, the lipid content was higher in the latter (9.1-10.6%) than in the former (7.6%).　 The lipid content in the nine-month culture fish was slightly higher in the BN group compared to the NN group. There was little difference in protein content between the young fish and the nine-month culture fish, or between the BN and NN groups. There was a slightly higher level of copper content in the liver (5ppm in the young fish and 5-6ppm in the nine-month culture fish) compared to the edible portions (1ppm in the young fish and 3-4ppm in the nine-month culture fish), but no difference was evident between the BN and NN groups. The prominent fatty acids were 16:0, 18:1n-9, 22:6n-3, 16:1n-7, 18:2n-6, 20:5n-3, and 18:0 in the edible portions of the young and cultured fish. The n-3 fatty acid content was slightly richer in the BN group.