Growth Characteristics of Juvenile Abalone, Haliotis discus hannai by Reared Methods in order to High Density Intermediate Culture in Land-based Tank

The effect of different intermediated rearing method by expanding the attached floor space in order to highly density culture on the growth characteristics and survival rate of the juvenile abalone, Haliotis discus hannai, were investigated in land-based tanks. The intermediated culture methods was determined thru the shelter counts and layer for 10 month with two replicates : the single layer shelter (SLS), the double layer shelter (DLS), the triple layer shelter (TLS) and the single layer shelter under net cage (SLSNC). In addition, the culture on shallow race way tank had to set up as culture of the ditch raceway tank (CDRT) and the floor race way tank (CFRT). In the growth performance of reared abalone (initial mean shell length $54.18{\pm}7.39mm$ and weight $1.93{\pm}0.14g$) at experimental tanks, that the absolute growth rate (ARG), daily growth rate (DGR) and specific growth rate (SGR) to the shell length and shell breadth was not significant at each experimental tanks except SLSNC. As well as too, weight gain (WG), daily weight gain (DWG) and specific weight gain (SWG) to weight was not significant at each experimental tanks except SLSNC, too. Survival rates of CDRT and CFRT was lower than those of different experimental tanks (P < 0.05). Therefore, these results is showed that high density different intermediated rearing method by expanding the attached floor space for juvenile H. discus hannai was not have difference as growth performance and survival rate both one layer shelter and multi layer shelter. Also, it is considered that shallow race way tank was not useful rearing for the juvenile intermediate culture of H. discus hannai in land based.

육성수조 내 북방전복, Haliotis discus hannai 치패 고밀도 중간양성 사육방식별 성장특성

본 연구는 북방전복 육상 수조 내 고밀도 중간양성 방법을 모색하기 위해 부착면적 확대를 위해 다단식 shelter 설치와 수조 내 중층 이상의 가두리를 설치하여 성장을 비교하고 아울러 전복류 육상 양성방법인 'shallow race way' 국내 도입 가능성을 조사하였다. Shelter 실험구는 PE (polyethylene) 재질의 shelter ($63{\times}98cm$) 1층형 (the single layer shelter, SLS), 2층형 (the double layer shelter, DLS), 3층형 (the triple layer shleter, TLS) 과 육상 가두리 양성방식 (the single layer shelter and net cage culture, SLSNC), 그리고 'shallow race way' 방식을 polyvinyl chloride (PVC)로 제작하여 고랑수로양성 (culture of the ditch raceway tank, CDRT)과 편평한 수로양성 (culture of the floor raceway tank, CFRT) 방식을 설정하였으며, 실험구는 모두 2반복으로 실시되었다. 각 실험구별 SLS 기준 60%밀도로 수용한 실험 전복 (최초 수용 시 평균각장 $25.19{\pm}0.50mm$, 중량 $1.93{\pm}0.14g$), 성장에서 각장의 절대성장율 (absolute growth rate, ARG), 일간성장율 (daily growth rate, DGR) 및 순간성장율 (specific growth rate, SGR) 과 중량의 증중률 (weight gain, WG), 일간증중률 (daily weight gain, DWG) 에서 SLSNC 제외한 모든 실험구가 유의적인 차이가 없었다. 그리고 생존율에서는 CDRT와 CFRT가 유의적으로 낮았다 (P < 0.05). 따라서 shelter를 이용하여 부착면적을 확대한 고밀도 전복치패 육상 중간육성 사육 시 단층과 다단층에서 성장과 생존율에서 차이가 없으며, 호주 등에서 사용되는 shelter 없는 'shallow race way'의 얇은 수심사육은 국내 북방전복 육상 중간양성 방식으로 도입하기에 적합하지 않는 것으로 판단된다.