Asian arowana, scleropages formosus aquaculture in Sarawak: early life cycle and genetic diversity in captivity

Mohd Khairulazman, Bin Sulaiman (2015) Asian arowana, scleropages formosus aquaculture in Sarawak: early life cycle and genetic diversity in captivity. Masters thesis, Universiti Malaysia Sarawak, (UNIMAS).

PDF (Please get the password by email to repository@unimas.my , or call ext: 082-583914/3973/3933) M Khairulazman.pdf Restricted to Registered users only Download (3MB)

Abstract

Asian arowana, Scleropages formosus or locally known as ‘ikan Kelisa’ is one of Malaysia potential resource. Asian arowana is native to Southeast Asia and it fetches extremely high price in ornamental fish industry. Due to unsustainable management and habitat deterioration they became rare and possibly extinct in their natural habitat. Hence, they are listed in Appendix I in Convention of International Trade in Endangered Species of Wild Fauna and Flora (CITES) and listed as ‘Endangered’ species in the International Union for Conservation of Natural Resources (IUCN) Red List of Threatened Species under species name Scleropages formosus. This study is designed to document the baseline data regarding the water quality of Asian arowana culture in earthen ponds, breeding behaviour of Asian arowana, artificial incubation of Asian arowana eggs and to discover genetic diversity of Asian arowana in captivity and phylogeny among colour varieties of Asian arowana. Weekly monitoring of in-situ ambience water quality had revealed pond water temperature, turbidity and hardness might influence the mating behaviour of Asian arowana. Spawning behaviour starts with pairing of one male and one female, swimming side by side in a precise manner followed by swimming into deeper parts of the ponds possibly for mating. In this study, custom-made incubators were also tested. Incubator A, which produce eggs movement rate up to 0.8 cm/s, has shown potential as incubator for arowana eggs with 95% survival rate. Meanwhile, 16S rRNA gene sequence were obtained from Asian arowana in this study revealed that sequence data matched 99% identical to S. formosus, Red arowana (GenBank accession number: JN984803.1). In addition, analysis also concluded that Golden Arowana from Bukit Merah and Bau farm has 0.2% genetic diversity which indicates high similarity in genetic composition. Besides, Asian arowana from Bau farm has greater genetic diversity (0.4%) from Bukit Merah (0.0%). Meanwhile, phylogenetic analysis shows that genus Scleropages were monophyletic and low genetic divergence was detected among each colour variants of S. formosus (<2%) indicates intra-specific variation of the species regardless of its colour variety. This finding challenges the proposed classification of Asian arowana based on its colour variety.

Actions (For repository members only: login required)

View Item