Bamboo as Potential Substrate for Sea Cage Culture of Abalone Haliotis asinina

Abstract

AbstractAbalone is highly priced marine gastropod in both domestic and overseas markets, but increased fishing pressure has caused a significant decline in the wild abalone population. To meet market demand, there is increasing interest in the cage culture of abalone juveniles. However, the use of polyvinyl chloride (PVC) substrate, the most used substrate in cage culture, has been associated with environmental and health risks. Thus, this study investigated the potential of bamboo slat (BS) as an alternative substrate for the bottom sea cage culture and suspended sea cage culture of tropical abaloneHaliotis asininafed with the red seaweedGracilaria firma. The results showed, during the 60–120 days of culture, abalone juveniles grown with BS substrate had significantly higher weight gain and specific growth rate compared to those reared with PVC substrate (p < 0.05). Nevertheless, the t-test conducted on day 150 indicated that the mean weight of abalone juveniles with the BS substrate was not significantly different from those with PVC substrate. The findings also indicate that abalone juveniles grown with BS substrate had significantly higher shell length growth rates than abalone juveniles grown with PVC substrate (p < 0.05). In addition, abalone juveniles on BS substrate showed positive allometric growth after 90 days and 150 days of culture compared to abalone juveniles on PVC substrates, which showed isometric growth. Furthermore, the t-test showed that survival rates of abalone juveniles with BS substrate are not significantly different compared with abalone juveniles with PVC substrate (p < 0.05). Since abalone juveniles cultured in cages with BS substrate have high growth and survival rates; thus, they are recommended as an alternative for abalone juvenile culture because they are indigenous, inexpensive, and environmentally safe.