The giant freshwater prawn (GFP), Macrobrachium rosenbergii has emerged as a significant crustacean in global aquaculture. A cradle-to-farm Life Cycle Assessment (LCA) was used to assess the potential environmental impacts of GFP in Malaysia. The four main iterative farming phases involved were pond preparation, stocking, farming, and harvesting. The impact categories chosen were global warming, terrestrial ecotoxicity, terrestrial acidification, freshwater eutrophication, human non-carcinogenic toxicity, human carcinogenic activity, and water consumption. The software SimaPro 9.3.0.3 was used for impact analysis, with background data from the database Ecoinvent 3.0. and ReCiPe 2016 Midpoint (H) V1.06/World (2010). Among other environmental impact categories, stocking and harvesting phases contributed to human carcinogenic toxicity impact values of 33.33%, followed by farming (33.31%). Another impact category, freshwater ecotoxicity also produces the same pattern with the stocking and harvesting process, still generating the highest impact value of 33.34%, followed by farming (33.30%). Apart from the identified capital items that require consideration for future waste management in aquaculture, this LCA study found that M. rosenbergii farming generates a low impact to the environment, however, could inspire further research on other perspectives of sustainability.

Pangasiids are an economically significant group of catfish, and many pangasiids are threatened in the wild from anthropogenic pressures, including increases in fishing pressure, habitat degradation, and improperly managed aquaculture practices. This study demonstrates the usage of DNA barcoding of the Cytochrome Oxidase subunit I (COI) gene as an identification tool in detecting potentially threatening invasive pangasiid species by establishing the diversity and phylogenetic relationship of Pangasiidae catfishes in Peninsular Malaysia. A neighbour-joining (NJ) dendrogram (Kimura-2-parameter model) generated five clades to represent distinct genera. Pangasius was further subdivided into two clades (Clade A: Pangasius bocourti-P. djambal and Clade B: P. nasutus-P. conchophilus). Given the marginal genetic divergence, indigenous and non-native species should be treated cautiously in allopatrically distributed species. The analysis used Automatic Barcode Gap Discovery (ABGD) and revealed barcode gaps between the intraspecific and interspecific distances. The sequences were partitioned into five groupings, corresponding with the species delineation based on the distribution of pairwise differences, which could not be differentiated using the NJ dendrogram. ABGD allows the recognition of one or two additional species using the recursive approach, but other taxonomic methods should be considered for a solid conclusion. DNA barcoding demonstrates the identification of closely related species, thus justifying its application towards the conservation of these fish.

The Asian Arowana, Scleropages formosus (Müller and Schlegel, 1844) is a large majestic freshwater teleost, crowned as the king of aquariums with its bright charismatic appearance and magnificent swimming performance. The most expensive Asian arowana is the Golden Blue-based Malayan Arowana which is endemic to the Bukit Merah Lake and Kerian River Basin, Perak, Malaysia. S. formosus has been listed as endangered by the IUCN (International Union for Conservation of Nature), regulated under Appendix 1 of the Convention of International Trade on Endangered Species (CITES) for commercial trade. Environmental DNA (eDNA) analysis has become widely accepted in biodiversity monitoring for the detection of rare and endangered species without harming any ecosystem or threatened species. Hence, the application of eDNA as wild population monitoring of S. formosus is possible for conservation and CITES enforcement program. • The species-specific primer of S. formosus was designed based on selected sequences obtained from GenBank • This report presents the potential application of eDNA in the management of the Malaysian 686 CITES Act for conservation monitoring of the Asian Arowana • The detection and wild population monitoring is possible through the eDNA method as complementary tools